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SIM808_Hardware Design_V1.02

1. 64 6 10 2 Module RF Receive Sensitivity esse 65 6 10 3 Module Operating Fr qu ncles ist minima mimi entente 66 SIMS808 Hardware Design V1 02 4 2015 04 09 Smart Machine Smart Decision BOE ICI VL as E 67 7 1 Top and Bottom View of diurne 67 7 2 Typical Solder Reflow Prohle 5 ete eter e e e ves cs 67 7 3 The Moisture Sensitivity Level issues 68 7 4 Baking Requirements Jm ette bd me addi edi 68 ENXIIL q 69 I Related Documents MEME 69 II Multiplexing Function 2 ertet ee ERR CSI RE EROS ECRIRE TERR RERO HEUTE 70 Terms and Abbreviations i ace 71 IV Safety Caution eg URP Id 73 SIMS808 Hardware Design V1 02 5 2015 04 09 Smart Machine Smart Decision Table Index TABLE 1 SIM808 GSM GPRS ENGINE KEY FEATURES eerte tentent tentent tis 11 TABLE 2 GPS ENGINE PERFORMANCE cnrs 13 TABLE 3 BT ENGINE PERFORMANCE etn pesca 13 TABLE 4 CODING SCHEMES AND MAXIMUM DATA RATES OVER AIR INTERFACE sm 14 TABLE 5 OVERVIEW OF OPERATING MODBES eet 15 TABLE 6 PIN DESCRIPTI
2. Module Figure 21 Connection of the serial port If the voltage of UART on the DTE side is 3 3V the following reference circuits are recommended And if the voltage is 3 0V please change the resistors in the following figure from 5 6K to 14K SIMS808 Hardware Design V1 02 35 2015 04 09 Smart Machine Smart Decision Module DTE 3 3V Figure 22 Level converting by resistor If the voltage of UART 15 or3 3V user also can use following reference circuits 10K VDD EXT O 1 RXD lt TXD TXD De O RXD 10K GND e O GND Module m DTE Figure 23 Isolation circuit by diodes Note when a diode used to isolate voltage cross customer should notice that there s voltage drop on the diode And the signals voltage level should meet the customer s electrical character The recommend diode is Schottky diode e g RB551V 30TE 17 and SDM20U40 If the voltage of UART is 5V on customer side customer can use the following reference circuits VDD EXT VDD EXT 47K VDD o 4 7K 47K TXD 14 121 RXD Module DTE Figure 24 TX level converting by transistor 8 808 Hardware Design V1 02 36 2015 04 09 Smart Machine Smart Decision
3. 57 4 21 3 GPS Antenna Interface NN 57 S i M secs 59 5 1 Pin 1 59 52 Principle of PCB Layouts nn in a er edita tedio EE 59 5 21 Antenna Interfaces A EN 59 5 2 2 Power Supply 59 5 2 3 SIM Card Interface siennes 59 5924 Ando MVI T fiU 59 92249 JC mh WERE 60 5 3 Recon Mod PCB Layout 60 6 Electrical Reliability and Radio 21 2 61 641 A DSONMS Maximum 8 44 61 6 2 Recommended Operating Conditions 61 6 3 Digital Interface Characteristics sise 61 6 4 SIM Card Interface Characteristics ss 61 6 5 SIM Characteristics E HER 62 6 6 VDD EXT Characteristics 62 6 7 Character 62 6 8 Current Consumption GPS engine is powered 63 6 9 Elecro staus Discharge 63 610 Radio Characteristics 64 6 10 1 Module RF Output Power
4. company of SIM Tech SIM808 Hardware Design V1 02 Smart Machine Smart Decision Document Title 51808 Hardware Design V1 02 Version 1 02 Date 2015 03 20 Status Release Document Control ID SIM808_ Hardware Design General Notes SIMCom offers this information as a service to its customers to support application and engineering efforts that use the products designed by SIMCom The information provided is based upon requirements specifically provided to SIMCom by the customers SIMCom has not undertaken any independent search for additional relevant information including any information that may be in the customer s possession Furthermore system validation of this product designed by SIMCom within a larger electronic system remains the responsibility of the customer or the customer s system integrator All specifications supplied herein are subject to change Copyright This document contains proprietary technical information which is the property of SIMCom Limited copying of this document and giving it to others and the using or communication of the contents thereof are forbidden without express authority Offenders are liable to the payment of damages All rights reserved in the event of grant of a patent or the registration of a utility model or design All specification supplied herein are subject to change without notice at any time Copyright Shanghai SIMCom Wireless Solution
5. RUNE EE EMEN NE 29 433 Wake Up SIM808 from Sleep Mode 29 4 4 Charging Interface 30 4 4 1 Battery Pack Characteristics seen 30 442 Recommend eNO 2 2222222222222 4 4 4 2241 40 2 0 00 01000 000 046 10800000400 000007 30 4 4 3 Implemented Charging Technique sise 31 4 4 4 Operating Modes during Charging ses 31 445 hane Nequirements ete 32 4 5 RIONBacK p 32 4 6 Serial Port and USB Interface ss 34 4 6 1 YFuncuon ot Serial 34 Port i Mn Idm LM 35 4 6 3 USB Interface 37 4 6 4 Software Upgrade and Debug sise 38 4 7 2 I 38 4 8 ACCS 39 4 8 1 Speaker Interface Configuration 4e 40 4 8 2 Microphone Interfaces Configuration ss 41 4 8 3 Audio Electronic Characteristics seen 41 484 41 4 9 SIM Card Interface eee eee e e e He E 42 8 808 Hardware Design V1 02 3 2015 04 09 Smart Machine Smart Decision 491 SIM Card Application eiit ERRORES
6. 61 63 RF SYNC 50 2 59 KBC3 58 KBRO 57 KBRI 129 KBR2 55 KBR3 SIMS08 Top View 22 23 24 amp Al zononuz aaasxtswtEk5no QO00 lI it amp 4 O P Ar B x d gt IA el LI ma x ERE zaun 133 ANT 52 GND 27 28 29 aif 32 33 34 Figure 2 SIM808 pin out diagram Top view SIMS808 Hardware Design_V1 02 S l amp 15 16 5 18 Ics 1 oo o o GND NETLIGHT STATUS PCM_OUT PCM_IN PCM_CLK PCM_SYNC GPIO17 GPIO19 PWMI PWM2 GND SCL SDA IPPS GND GPS_ANT 2015 04 09 Reema Tesh Smart Machine Smart Decision 3 2 Pin Description Table 6 Pin description SIMS808 Hardware Design V1 02 2015 04 09 Smart Machine Smart Decision SIM808 Hardware Design 1 02 2015 04 09 Smart Machine Smart Decision NETLIGHT 50 O Network status Can not multiplex with STATUS 49 Power on status GPIO function 3 3 Package Dimensions Figure3 Dimensions of SIM808 Unit mm SIMS808 Hardware Design V1 02 20 2015 04 09 Qeeee ERE 3 ee porri Smart Machine Smart Decision 4 00 m s S ss O Cul SIM808 Area Keep out Area Figure 4 Recommended PCB footprint outline Unit mm SIMS808 Hardware Design_V1 02 21 2015 04 09 Smart Machine Smart Decision 4 Application Interface 4 1 Power Supply The power supply r
7. Figure 17 SIM808 with battery charger and pack connection 4 4 1 Battery Pack Characteristics SIM808 has optimized the charging algorithm for the Li ion battery that meets the characteristics listed below The maximum charging voltage of the Li ion battery pack is 4 2V and the recommended capacity is SIMS808 Hardware Design V1 02 30 2015 04 09 Smart Machine Smart Decision 1100mAh The Battery packs with more than 1100 mAh capacity will take more time for charging The battery pack should have a protection circuit to avoid overcharging deep discharging and over current and the circuit should be insensitive to pulsed current The internal resistance of the battery pack including protection circuit should be as low as possible Its recommended value does not exceed 150mQ The battery pack must be protected from reverse pole connection On the SIM808 the build in circuit of the power management chipset monitors the supply voltage constantly Once the Under voltage is detected the SIM808 will be powered off automatically 4 4 2 Recommended Battery Pack Following 1 the specification of recommended battery pack Table 10 Specification of recommended battery pack Items Description Battery type Li ion Manufacturer Jiade Energy Technology Normal voltage 3 7 Capacity NORMAL 1100mAh Charge Voltage 4 200 0 050V Max Charge Current 1 0C Charge Method CC CV Constant Current Constant Voltage Max Discharge C
8. VDD_EXT VDD_EXT VDD 4 7K 4 7K 47K RXD A TXD Module DTE Figure 25 RX level converting by transistor Note The recommend Transistors part numbers are 28C4617TLR and PBHVS8115Z 4 6 3 USB Interface USB interface supports software debug firmware upgrade do not support AT command by default When power on the module connect VCHG USB DP USB DN and GND to PC then install the driver successfully port could be recognized by the PC customer can achieve the software Debug purpose with this UART port The following diagram is recommended VBUS VBUS USB_DNO USB DN USB DPO e QUSB DP luF OID GND GND FRA Module L L t USB Figure 26 USB reference circuit The maximum allowable cap load of TVS on USB data line should be less than SpF e g ESD9L5 0ST5G and ESD9MS5 0ST5G The USB DP and USB DN should be routed in differential traces Note please reserve the USB interface or test point for debug and firmware upgrade Table 13 Serial port characteristics Pin Min Typ Max Unit VCHG 4 3 5 0 7 0 V SIMS808 Hardware Design V1 02 37 2015 04 09 Smart Machine Smart Decision 4 6 4 Software Upgrade and Debug Both serial port and USB interface can be used for firmware upgrade If customer upgrading firmware via the USB port with the download tool SIM808 power pin VBAT must be supplied first then connect VCHG USB_DP USB_DN
9. FIGURE 11 POWERED ON DOWN MODULE USING BUTTON Dee nenne 25 FIGURE 12 TIMING OF POWER ON 2 gene aene enn 25 FIGURE 13 TIMING OF POWER ON MODULE 26 FIGURE 14 TIMING OF POWER OFF SIM808 BY PWRKEY Miss 26 FIGURE 15 RESET CIRCUIT s 28 FIGURE 16 RESET TIMING SEQUBEN QGE retten 29 FIGURE 17 SIM808 WITH BATTERY CHARGER AND PACK CONNECTION ms 30 FIGURE 18 RTC SUPPLY FROM eese pfe 33 FIGURE 19 SUPPLY FROM NON CHARGEABLE BATTERY 5 eese nennen ene rennen 33 FIGURE 20 RTC SUPPLY FROM RECHARGEABLE BATTERY 33 FIGURE 21 CONNECTION OF THE SERIAL PORT huissiers 35 FIGURE 22 LEVEL CONVERTING BY 5 eene enne enne 36 FIGURE 23 ISOLATION CIRCUIT BY DIODES AN Nuestra 36 FIGURE 24 TX LEVEL CONVERTING BY 36 FIGURE 25 RX LEVEL CONVERTING BY TRANSISTOR sise 37 FIGURE 26 USB REFERENCE CIRCUM inso toits tenete 37 FIGURE 27 RI BEHAVIOUR OF VOICE CALLING AS A eene rere 38 FIGURE 28 RI BEHAVIOUR OF DATA CALLING AS RECEIVER seen een en ene n enn eene 39 FIGURE 29 RI BEHAVIOUR OF URC OR RECEIVE SMS 39 FIGURE 30 RI BEHAVIOUR
10. AS A CALLER 39 FIGURE 31 SPEAKER VEFBRENCE CIRCUIT 0 nene tren tret tren reet nette nennen entrent 40 FIGURE 32 SPEAKER WITH AMPLIFIER REFERENCE CIRCUIT 40 FIGURE 33 MICROPHONE REFERENCE CIRCUIT 41 FIGURE 34 REFERENCE CIRCUIT OF THE 8 PIN SIM CARD 42 FIGURE 35 REFERENCE CIRCUIT OF THE 6 PIN SIM CARD HOLDER eee ee 43 FIGURE 36 MOLEX 91228 SIM CARD HOLDER 1 1 theta tineis ensi cases 44 FIGURE 37 AMPHENOL C707 10 006 512 2 SIM CARD eene ene eene 45 FIGURE 38 PCM REFERENCE CIRCUIT 46 FIGURE 39 LCD REFERENCE CIRCUIT 47 FIGURE 40 SD REFERENCE CIRCUL re tete a ioe s EE 47 FIGURE 41 TRADITIONAL KEYPAD REFERENCE CIRCUIT eee 48 FIGURE 42 ENHANCE THE ESD PERFORMANCE OF KEYPAD CIRCUIT 49 FIGURE 43 GPIO TIMING SEQUENCES REI eee E FOR PIRA 50 FIGURE 44 REFERENCE CIRCUIT OF PWM DRIVE BUZZER sisi 51 FIGURE 45 REFERENCE CIRCUIT OF NETLIGHT inner 53 FIGURE 46 RF SYNC SIGNAL DURING TRANSMIT BURST sis 54 FIGURE 47 GSM ANTENNA MATCHING CIRCUIT seen en en nennen trennen trennen rennen 56 SIMS808 Hardware Design V1 02 20
11. Data GPRS CSD USSD SMS SIM interface External antenna Audio features Serial port and USB interface Phonebook management SIM application toolkit Real time clock Alarm function Physical characteristics 8 808 Hardware Design V1 02 Smart Machine Smart Decision SIM808 Quad band GSM 850 EGSM 900 DCS 1800 PCS 1900 SIM808 can search the 4 frequency bands automatically The frequency bands also can be set by AT command AT CBAND For details please refer to document 1 Compliant to GSM Phase 2 24 Class 4 2W at GSM 850 and EGSM 900 Class 1 IW at DCS 1800 and PCS 1900 GPRS multi slot class 12 default GPRS multi slot class 1 12 optional Normal operation 40 C 85 C Storage temperature 45 C 90 C GPRS data downlink transfer max 85 6 kbps GPRS data uplink transfer max 85 6 kbps Coding scheme CS 1 CS 2 CS 3 and CS 4 PAP protocol for PPP connect Integrate the TCP IP protocol Support Packet Broadcast Control Channel PBCCH CSD transmission rates 2 4 4 8 9 6 14 4 kbps Support CSD transmission Unstructured Supplementary Services Data USSD support MT MO CB Text and PDU mode SMS storage SIM card Support SIM card 1 8V 3V Antenna pad Speech codec modes Half Rate ETS 06 20 Full Rate ETS 06 10 Enhanced Full Rate ETS 06 50 06 60 06 80 Adaptive multi rate AMR Echo Cancellation Noise Suppression Serial port Full modem interface
12. GSM_ ANT pin and antenna is not enough the matching circuit could be simplified as the following figure SIM808_Hardware Design_V1 02 56 2015 04 09 Smart Machine Smart Decision GSM Mo dul e Antenna R101 101 C102 Figure 48 GSM simple antenna matching circuit 4 22 2 Bluetooth Antenna Interface The module provides a Bluetooth antenna interface named ANT The external antenna must be matched properly to achieve best performance so the matching circuit is necessary the connection is recommended as the following figure GND Module ini BT BT ANT Antenna C201 T c202 GND Figure 49 Bluetooth antenna matching circuit R201 201 C202 are the matching circuit the values depend on antenna debug result Normally R201 is 02 C201 and C202 are not mounted 4 22 3 GPS Antenna Interface The module also provides a GPS antenna interface named GPS ANT to connect the antenna on the customer s application board obtain excellent GPS reception performance a good antenna will always be required Proper choice and placement of the antenna will ensure that satellites at all elevations can be seen and therefore accurate fix measurements are obtained There are two normal options passive antenna and active antenna GPS antenna choice should be based on the designing product and other conditions For detailed Antenna designing consideration
13. PHERUREUER IH AEHRIGEN ISIN IRIS 42 4 9 2 SIM Card Design Consideration ee 43 493 Design Considerations for SIM Card Holder 43 4 10 PCM Interface aaa a aaa aaa iS 45 4 10 1 PCM Multiplex Function 46 4 10 2 46 4 10 3 LED Display SPI Interface en erae De ee c e Re ees 47 4 10 4 SD Card Interface RM 47 4 1 NNO E 47 412 50 4 13 General Purpose Input Output GPIO 50 51 4 15 PWM EE 51 4 16 Network Status Indication sie Marles 52 4 17 Operating Status MdICAHOM a traine sn aged yere 53 4 18 Synchronization Signal 53 BAD oae 54 54 4 20 1 A 54 4 20 2 GPS Operating Modes annees 55 4 20 3 I PPS Outp t et A a hasan i e ER die redis cete deg 55 4 21 Antenna Interface aset 55 4 21 1 GSM Antenna Interface nus Ne NA One DEUS 56 4 21 2 Bluetooth Antenna amp
14. SIM808_Hardware Design_V1 02 55 2015 04 09 Smart Machine Smart Decision The input impendence of the antenna should be 50Q and the VSWR should be less than 2 The traces from antenna pads to the corresponding antenna connections on the customer s application board should be treated 50Q impedance in PCB layout It is recommended that the three antennas are placed far away from each other The isolations of the three antennas should be more than 30dB Note About the RF trace layout please refer to AN_SMT Module RF Reference Design Guide 4 221 GSM Antenna Interface There is a GSM antenna pad named GSM ANT to connect an external GSM antenna the connection of the antenna must be decoupled from DC voltage This is necessary because the antenna connector is DC coupled to ground via an inductor for ESD protection The external antenna must be matched properly to achieve the best performance so the matching circuit is necessary the connection is recommended as following GSM s Antenna Module RF Connector GSM ANT R10 C101 C102 Figure 47 GSM antenna matching circuit R101 C101 C102 the matching circuit the values depend on antenna debug result Normally R101 is 00 C101 and C102 are not mounted The RF connector is used for conducted test and should be placed as close as possible to the module s GSM ANT pad If the space between
15. VDD_SD Q gt Q VDD GPIO17 O CLK GND GND STATUS O DATO NETLIGHT O di DATI Module 0 Figure 40 SD reference circuit When needed the SD card interface should be multiplexed as follows Pin name Pin number Mode 0 default Mode 1 Mode 2 SIM_DET 33 SIM DET SD_DAT3 GPIO36 GPIO17 44 GPIO31 SD_CLK GPIO19 43 GPIO32 SD_CMD DCD 11 DCD SD_DAT2 NETLIGHT 50 NETLIGHT SD DATI SDTATUS 49 STATUS SD DATO If the VDD of SD card is 2 8V user can use VDD EXT power the SD card directly If the VDD is 3 3V customer should design the power circuit external SIMS808 Hardware Design V1 02 47 2015 04 09 Smart Machine Smart Decision Note This function is not supported in the standard firmware If user wants this function the firmware must be customized Please contact SIMCom for more details 4 12 Keypad Interface SIM808 consists of 4 keypad column outputs and 4 keypad row inputs z pi KBROC 9 9 1 KBR2 i Q1 OF Q Q 0 KBR3C Figure 41 Traditional keypad reference circuit Note 1 According to the traditional 4 4 keypad matrix when there are unused COLs or ROWs user can execute AT command to define unused COLs and ROWs as GPIO for details please see the document 1 2 Press COLO and ROW or pull down COLO when power on PWRKEY Charging RTC alarm power sequence is USB Downlo
16. and the mode serial port is still accessible The power consumption in this mode is lower than normal mode SIMS808 Hardware Design V1 02 15 2015 04 09 Smart Machine Smart Decision 2 3 SIM808 Functional Diagram The following figure shows a functional diagram of SIM808 PMU The GSM baseband engine The GPS engine The GSM Radio Frequency part The antenna interface The other interfaces gt Radio GSM Power Power management unit Frequency supply T Digital Interface GPS e Receiver cil UART lt gt e Analog Digital e 88 da p hele a Analog Interface ne Baseband Baseband los PWMs gt 2 lt gt Audio quam LE gt PCM gt ADC USB gt Figure 1 SIM808 functional diagram SIM808_Hardware Design_V1 02 16 2015 04 09 Smart Machine Smart Decision 3 Package Information 3 1 Pin out Diagram 68 GND 187 GND 66 GSM ANT GND GND GND VBAT VBAT VBAT VDD_EXT PWRKEY DTR RI DCD CTS RTS IS 100 1 4 18 I Lo t2 1 IS 15 15 IE do Is IF a Sm 185 GND 54 GND 20 at 62
17. from the network and allows the software to enter into a secure state to save data before completely shut down Before the completion of the power off procedure the module will send URC NORMAL POWER DOWN At this moment commands can not be executed any more and only the 1 still active Power off mode can also be indicated by STATUS pin which is at low level at this time 4 2 2 2 Power off SIM808 by AT Command SIM808 can be powered off by AT command AT CPOWD 1 This procedure makes the module log off from the network and allows the software to enter into a secure state to save data before completely shut down Before the completion of the power off procedure the module will send URC NORMAL POWER DOWN At this moment AT commands can not be executed any more and only the RTC is still active Power off mode can also be indicated by STATUS pin which is at low level at this time For detail about the AT command please refer to document 4 2 2 3 Over voltage or Under voltage Power off The module software monitors the VBAT voltage constantly If the voltage x 3 5V the following URC will be reported UNDER VOLTAGE WARNNING If the voltage 7 4 3V the following URC will be reported OVER VOLTAGE WARNNING If the voltage 3 4V the following URC will be reported and the module will be automatically powered off UNDER VOLTAGE POWER DOWN If the voltage gt 4 4V the following will be r
18. of USB and 2 5 3 Recommended PCB Layout Based on above principles recommended layout is shown in the following illustration SIM808 Interface Top View GPS_ANT VBAT Audio USB SIM Card Interface Interface Figure 52 PCB layout pinout example SIMS808 Hardware Design 1 02 60 2015 04 09 Smart Machine Smart Decision 6 Electrical Reliability and Radio Characteristics 6 1 Absolute Maximum Ratings The absolute maximum ratings stated in following table are stress ratings under non operating conditions Stresses beyond any of these limits will cause permanent damage to SIM808 Table 39 Absolute maximum ratings VBAT V Peak Current 0 2 0 A VCHG 12 I 16 mA Io 16 mA These parameters are for digital interface pins such as keypad GPIO I2C UART PWM and PCM 6 2 Recommended Operating Conditions Table 40 Recommended operating conditions VBAT Power supply voltage 3 4 4 0 4 4 Operating temperature 40 25 85 6 Storage temperature 45 90 6 3 Digital Interface Characteristics Table 41 Digital interface characteristics High level input voltage V Vit Low level input voltage 0 3 0 7 High level output voltage 2 4 2 8 Vor Low level output voltage 0 4 These parameters are for digital interface pins such as keypad UART LCD PWMs and DEBUG SIMS808 Hardware Design_V1 02 61 2015 04 09 rea et Smart Mach
19. than 90 If the condition meets one of the following ones shown below the modules should be baked sufficiently before re flow soldering and the baking condition is shown in below table otherwise the module will be at the risk of permanent damage during re flow soldering If the vac um package is broken or leakage If the vacuum package is opened after 6 months since it s been packed If the vacuum package is opened within 6 months but out of its Floor Life at factory ambient 30 C 60 RH or as stated Table 53 Baking requirements Baking temperature Moisture Time 40 C 5 C lt 5 192 hours 120 C 5 C lt 5 6 hours Note Care should be taken if that plastic tray is not heat resistant the modules should be taken out for preheating otherwise the tray may be damaged by high temperature heating SIM808_Hardware Design_V1 02 68 2015 04 09 Smart Machine Smart Decision I Related Documents Table 54 Related documents SN Document name Remark SIM808 Series AT Command 1 Manual 2 SIM808 TCP IP Applications User Manual Series TCPIP Application Note_ 3 Du UART Port Application Note 4 AN Serial Port AN Serial Port AN SMT 5 Module RF Reference Design Guide 6 Module secondary SMT UGD Module secondary SMT User Guide ITU T Draft new 7 Serial asynchronous automatic dialing and control recommendation V 25ter 8 SIM808 GPS Application Note SIM808 Series Bluetooth Appl ication Note 9 Di
20. the following figure SIM Card SIM VDD exp L SIM RST R vop l SIM CLK CIK SIM DET MODULE C707 10M006 512 2 SIM DATA ML d Figure 35 Reference circuit of the 6 pin SIM card holder 4 9 2 SIM Card Design Consideration SIM card circuit is susceptible to interference causing the SIM card failures or some other situations so it is strongly recommended to follow these guidelines whil designing Make sure that SIM card holder should far away from GSM antenna while in PCB layout SIM traces should keep away from lines VBAT and high speed signal lines The traces should be as short as possible Keep SIM holder s GND connect to main ground directly Shielding the SIM card signal by ground well Recommended to place capacitor on VSIM line and keep close to the holder Add some TVS and the parasitic capacitance should not exceed 50pF 4 9 3 Design Considerations for SIM Card Holder For 8 pins SIM card holder SIMCom recommends to use Molex 91228 User visit http www molex com for more information about the holder 8 808 Hardware Design V1 02 43 2015 04 09 E C Smart Machine Smart Decision pep Le RECOMMENDED PCB LAYOUT 2 1 NOTES L SEE PRODUCT SPECIFICATION PS 99020 007 2 PACKING TAPE AND REEL For DETAIL SEE 50 91228 9001 SHT 3 PUSH ROD LEVER
21. the module s VCHG Pin and the valid battery is connected to the VBAT Pin while SIM808 is in POWER DOWN mode SIM808 will auto power up 4 4 5 Charger Requirements Following is the requirements of charger for SIM808 Simple transformer power plug Output voltage 5 0V 7V Minimum supply current 1 0 C A 10V peak voltage is allowed for maximum 1ms when charging current is switched off 1 6 peak current is allowed for maximum 1ms when charging current is switched on 4 5 RTC Backup Current input for RTC when the VBAT is not supplied for the system Current output for backup battery when the VBAT power supply is in present and the backup battery is in low voltage state The RTC power supply of module can be provided by an external capacitor or a battery non chargeable or rechargeable through the VRTC The following figures show various reference circuits for RTC back up 8 808 Hardware Design V1 02 32 2015 04 09 Smart Machine Smart Decision External capacitor for RTC Module Large capacitance Capacitor Figure 18 RTC supply from capacitor Non chargeable battery for RTC Module Non chargeable Backup Battery Figure 19 RTC supply from non chargeable battery Rechargeable battery for RTC Module 1 5K RTC VRTC Rechargeable Backup Battery Figure 20 RTC supply from rechargeable battery Coin type rechargeable battery is recommended NOTE When
22. 15 04 09 Smart Machine Smart Decision GSM SIMPLE ANTENNA MATCHING CIRCUIT inner 57 BLUETOOTH ANTENNA MATCHING CIRCUIT iii 57 GPS PASSIVE ANTENNA MATCHING CIRCUIT 58 GPS ACTIVE ANTENNA 2 58 PCB LAYOUT PINOUT EXAMPLE rite eret ete etre her eerte to br retra Ree 60 TOP AND BOTTOM VIEW OF 5 808 67 TYPICAL SOLDER REFLOW PROFILE ss nnnm nenne ennt nete retener nennen 67 SIMS808 Hardware Design V1 02 9 2015 04 09 Qeeee ont Version History m Smart Machine Smart Decision SIM808_Hardware Design_V1 02 8 2015 03 20 Smart Machine Smart Decision 1 Introduction This document describes SIM808 hardware interface in great detail This document can help user to quickly understand SIM808 interface specifications electrical and mechanical details With the help of this document and other SIM808 application notes user guide users can use SIM808 to design various applications quickly 2 SIM808 Overview Designed for global market SIM808 is integrated with a high performance GSM GPRS engine a GPS engine and a BT engine SIM808 is a quad band GSM GPRS module that works on frequencies GSM 850MHz EGSM 900MHz DCS 1800MHz and PCS 1900MHz SIM808 features GPRS multi slot class 12 class 10 optional and supports the GPRS coding schemes CS 1 CS 2 CS 3 and CS 4 The GPS solution offers best in class acquisition and tracing sensit
23. 301 URL www sim com wm 8 808 Hardware Design V1 02 74 2015 04 09
24. 57 ROWI GPIO20 KBR2 I PD 56 ROW2 GPIO19 KBR3 I PD 55 ROW3 GPIO18 PWMI IPD 42 GPIO2 PWM2 IPD 41 PWMI GPIO3 PCM_OUT IPD 48 PCM OUT GPIO28 PCM IN IPD 47 GPIO27 PCM SYNC IPD 45 PCM SYNC GPIO29 PCM CLK I PD 46 PCM CLK GPIO26 GPIO17 IPD 44 GPIO31 SD_CLK GPIO19 IPD 43 GPIO32 SD_CMD DTR I PD 9 DTR EINT16 RI I PD 10 RI DCD I PD 11 DCD SD DAT2 CTS I PD 12 CTS 4 RTS I PD 13 RTS GPIOI5 TXD I PD 14 TXD RXD I PD 15 RXD SCL I PD 39 SCL GPIO43 SDA I PD 38 SDA GPIO44 NETLIGHT 50 NETLIGHT SD DATI SDTATUS IPD 49 STATUS SD DATO Note 1 Multiplexing function need different software version SIMS808 Hardware Design V1 02 70 2015 04 09 Terms and Abbreviations Table 56 Terms and Abbreviations 2015 04 09 gt x 2 a 2 gs lt gt N Smart Machine Smart Decision aS 27 e SIMS808 Hardware Design V1 02 72 2015 04 09 Lt Smart Machine Smart Decision IV Safety Caution Table 57 Safety caution MINIS Td S S SIM808_Hardware Design_V1 02 73 2015 04 09 ees See See of SIM Acompany Smart Machine Smart Decision Contact us Shanghai SIMCom Wireless Solutions Ltd Add SIM Technology Building No 633 Jinzhong Road Changning District Shanghai China 200335 Tel 86 21 3252 3300 Fax 86 21 3252 3
25. F OUTPUT POWER ss 64 SIM808 DCS 1800 AND PCS 1900 CONDUCTED RF OUTPUT POWER 65 SIM808 CONDUCTED RF RECEIVE 65 SIM808 OPERATING 5 66 MOISTURE CLASSIFICATION LEVEL AND eee en 68 BAKING REQUIREMEPENLLS eto 68 RELATED DOCUMENTS C 69 MULTIPLEXING EUNCTION eret otn oett NE tea 70 TERMS AND ABBREVIATIONS ssi sacs inis fort reta e ANORA STES EE FUERO ERE ERE EET 71 SAFETY CAUTION M 73 SIMS808 Hardware Design V1 02 7 2015 04 09 Smart Machine Smart Decision Figure Index FIGURE 1 SIM808 FUNCTIONAL 16 FIGURE 2 SIM808 PIN OUT DIAGRAM TOP 17 FIGURE 3 DIMENSIONS SIM808 UNIT MM rennes 20 FIGURE 4 RECOMMENDED PCB FOOTPRINT OUTLINE UNIT MM 21 FIGURE 5 REFERENCE CIRCUIT OF THE VBAT 22 FIGURE 6 REFERENCE CIRCUIT OF THE LDO POWER SUPPLY iii 23 FIGURE 7 REFERENCE CIRCUIT OF THE DC DC POWER SUPPLY eene eem ener 23 FIGURE 8 VBAT VOLTAGE DROP DURING TRANSMIT 23 FIGURE 9 THE MINIMAL VBAT VOLTAGE REQUIREMENT AT VBAT DROP see e 24 FIGURE 10 POWERED ON DOWN MODULE USING 24
26. IN DEFINITION OF THE 51 TABLE 30 SPECIFIC 51 TABLE 31 PIN DEFINITION OF THE PWM 51 TABLE 32 BUZZER OUTPUT CHARACTERISTICS seen 52 TABLE 33 PWM MULTIPLEX FUNCTION eee 52 TABLE 34 PIN DEFINITION OF THE NETLIGHT sens 52 TABLE 5 STATUS OF THE NETLIGHT PIN 52 TABLE 36 PIN DEFINITION OF THE STATUS rennes 53 TABLE 37 DEFINITION OF THE RF SYNC PIN tentent tentent ttt 53 TABLE 38 AT COMMANDS FOR GPS nes 55 TABLE 39 ABSOLUTE MAXIMUM RATINGS treten tentent 61 TABLE 40 RECOMMENDED OPERATING CONDITIONS nes 61 TABLE 41 DIGITAL INTERFACE CHARACTERISTICS eerte tentent tte tts 61 TABLE 42 SIM CARD INTERFACE CHARACTERISTICS eet 61 TABLE 43 SIM VOD CHARACTERISTICS utei sitit print tu 62 TABLE 44 VDD EXT CHARACTERISTICS mens 62 TABLE 45 VRTC CHARACTERISTICS manie 62 TABLE 46 GSM CURRENT CONSUMPTION nes 63 TABLE 47 THE ESD CHARACTERISTICS TEMPERATURE 25 C HUMIDITY 45 94 mes 64 SIM808_Hardware Design_V1 02 6 2015 04 09 m Acompany TABLE 48 TABLE 49 TABLE 50 TABLE 51 TABLE 52 TABLE 53 TABLE 54 TABLE 55 TABLE 56 TABLE 57 eseo Smart Machine Smart Decision SIM808 GSM 900 AND GSM 850 CONDUCTED R
27. MUST NOT PROTRUDE 0 HOUSING EDGE IN THIS AREA ILS ON EACH SIDE OF CONNECTOR TO LIE WITHIN O lZmm OF EACH OTHER ITEM COMPONENT MATERIAL HOUSING LIQUID CRYSTAL POLYMER LCP 30 GLASS FILL UL84 V O COLOUR BLACK 97 TERMINAL 0 15 PHOSPHOR BRONZE MIN Au OVER Pd NIIN CONTACT AREA 2 5 MIN Sn ON SMT TAILS V PUSH BUTTON 1 GF NYLON 46 YELLOW SPRING 0 25 STAINLESS STEEL V PUSH ROD 0 4 STAINLESS STEEL W LEVER 1 0 4 STAINLESS STEEL REVISIONS MOLEX EUROPE e a gor iq ee nm Figure 36 Molex 91228 SIM card holder Table 19 Pin description Molex SIM card holder SIM VDD SIM card power supply C2 SIM RST SIM card reset C3 SIM CLK SIM card clock C4 GND Connect to GND CS GND Connect to GND C6 VPP Not connect C7 SIM DATA SIM card data I O C8 SIM DET Detect SIM card presence For 6 pin SIM card holder SIMCom recommends to use Amphenol C707 10M006 512 2 User can visit http Awww amphenol com for more information about the holder SIMS808 Hardware Design V1 02 44 2015 04 09 Smart Machine Smart Decision CARD ACCORDING TO 6911 11 DIMENSION ONLY DURING LOCKING OPDRRATIN Figure 37 Amphenol C707 card holder Table 20 Pin description Amphenol SIM card 4 10 Int SIM808 AN interface Table 21 PCM pin definition SIM808 PCM
28. ON acuta vci mte bum omn a m pt dic RO eme 18 TABLE 7 RECOMMENDED ZENER DIODE nn 22 TABLE 8 ELECTRONIC CHARACTERISTIC OF THE RESET PIN 28 TABLE 9 THE CURRENT CONSUMPTION OF FUNCTION MODES AT CSCLK 1 me 29 TABLE 10 SPECIFICATION OF RECOMMENDED BATTERY PACK cens 30 TABLE 11 SERIAL PORT AND USB PIN DEFINITION sde Dufr 34 TABLE 12 SERIAL PORT CHARACTERISTICS ge tenens 34 TABLE 13 SERIAL PORT CHARACTERISTICS eene anann tentent tentis 37 de ta na S 38 TABLE 15 AUDIO INTERFACE DEFINITION nee 39 TABLE 16 MICROPHONE INPUT CHARACTERISTICS ner 41 TABLE 17 AUDIO OUTPUT CHARACTERISTICS ends tentent tentent 41 TABLE 18 SIM PIN DEFINITION men ge Mans 42 TABLE 19 PIN DESCRIPTION MOLEX SIM CARD HOLDER share 44 TABLE 20 PIN DESCRIPTION AMPHENOL SIM CARD HOLDER rennes 45 TABLE 21 PCM PIN DEFINITION nee De trente tette 45 TABLE 22 PCM PIN SPECIFICATION e Que 46 TABLE 23 PCM MULTIPLEX FUNCTION tte tte ttt ttti 46 TABLE 24 PIN DEFINITION OF THE KEYPAD INTERFACE eene tenens 49 TABLE 25 KEYPAD MULTIPLEX 50 TABLE 26 PIN DEFINITION OF THE IC 50 TABLE 27 12 MULTIPLEX EUNCPRUNM M ne ome pe nn 50 TABLE 28 PIN DEFINITION OF THE GPIO ner 50 TABLE 29 P
29. The Bluetooth performance please refer to table 3 The feature of Bluetooth is listed as below Fully compliant with Bluetooth specification 3 0 2 1 EDR Support operation with GPS and GSM GPRS worldwide radio systems Supports class output power Up to 4 simultaneous active ACL links Support sniff mode Support PCM interface and built in programmable transcoders for liner voice with transmission 4 21 GPS 4 21 1 GPS Overview SIM808 provide a high performance L1 GPS solution for cellular handset applications The solution offers best in class acquisition and tracking sensitivity Time To First Fix TTFF and accuracy The GPS engine supports both fully autonomous operations for use in handheld consumer navigation devices and other standalone navigation systems The module supports GPS QZSS SBAS ranging WAAS EGNOS GAGAN MSAS GPS engine Performance please refer to Table 2 All the GPS function is controlled by AT command via serial port And the GPS NMEA information is output SIM808_Hardware Design_V1 02 54 2015 04 09 Smart Machine Smart Decision also by serial port The default baud rate is 115200bps The GPS functions of AT commands are listed in the following table Table 38 AT Commands for GPS function Command Description AT CGPSPWR GPS power control AT CGPSRST GPS mode reset hot warm cold AT CGPSSTATUS Get current GPS status AT CGPSOUT GPS NMEA data output control AT CGPSINF Get current GPS location i
30. ad Customer should add resistor to enhance the ESD performance and the value of resistor should be less than 1KQ the connection diagram is shown in follow figure as an example SIM808_Hardware Design_V1 02 48 2015 04 09 KBCx O lt 1K Module KBRx Q Smart Machine Smart Decision Figure 42 Enhance the ESD performance of keypad circuit Table 24 Pin definition of the keypad interface KBCO KBCI KBC2 KBC3 KBRO KBRI KBR2 KBR3 61 60 59 58 57 56 55 Keypad matrix column Keypad matrix row Table 25 Keypad multiplex function KBCO KBCI KBC2 KBC3 KBRO KBRI KBR2 KBR3 61 60 59 58 57 56 55 COLO COLI COL2 COL3 ROWO ROWI ROW2 ROW3 Note Multiplex Function need different software version 4 13 12 Bus Pull up Pull up Pull up Pull up Pull down Pull down Pull down Pull down GPIO16 GPIO14 GPIO13 GPIO12 GPIO21 GPIO20 GPIO19 GPIO18 The SIM808 provides an I2C interface it can be driven by either the master or slave and conform to the I2C specification SIM808_Hardware Design_V1 02 49 2015 04 09 HE HE ee Acompam E ione Smart Machine Smart Decision Table 26 Pin definition of the I2C SCL serial bus clock SDA 38 I2C serial bus data Note I2C has been pulled up internal to 2 8V via 4 7KQ Table 27 12 multiplex function SCL SCL GPIO43 SDA 38 SDA GPIO44 Note Multiplexing f
31. an protect the whole circuit in case the active antenna is shorted to ground SIM808_Hardware Design_V1 02 58 2015 04 09 Smart Machine Smart Decision 5 PCB Layout Usually most electronic products with good performance are based on good PCB layout bad PCB layout will lead to lots of issues like noise SIM card can not be detected etc The final solution for these problems 1 to redo PCB layout Making good PCB layout at beginning will save development schedule and cost as well This section as below will give some guidelines on PCB layout 5 1 Pin Assignment Before PCB layout we should learn well about pin assignment in order to get reasonable layout with so many external components Please refer figure2 for details 5 2 Principle of PCB Layout During layout attention should be paid to the following interfaces like Antenna power supply SIM card interface audio interface and so on 5 2 1 Antenna Interface There are some suggestions for components placing and routing of GSM and Bluetooth RF traces The RF connector is used for conducted test so keep itas close to the GSM ANT pin as possible Antenna matching circuit should be close t the antenna Keep the RF traces as 500 The RF traces should be kept far away from the high speed signals and strong disturbing source If using a RF cable kept it far away from SIM card power ICs It is recommended that GSM antenna and Bluetooth antenna be placed as
32. and GND to PC There is no need to operate PWRKEY pin in the whole procedure when SIM808 detects VCHG and could communicate normally by USB_DP and USB_DN module will enter USB download mode automatically Note When only USB DP and USB DN connected VCHG customer need to pull down COLO before power on the module then press the PWRKEY button the module will enter download mode Also only the USB interface can be used to debug by default 4 7 RI Behaviors Table 14 RI Behaviors State RI response Standby High The pin is changed to low When any of the following events occur the pin will be changed to high Noise call 1 Establish the call 2 Hang up the call The pin is changed to low When any of the following events occur the pin will be changed to high Data call 1 Establish the call 2 Hang up the call SMS The pin is changed to low and kept low for 120ms when a SMS is received Then it is changed to high Um The pin is changed to low and kept low for 120ms when some URCs are reported Then it is changed to high For more details please refer to document 4 The behavior of the RI prn is shown in the following figure when the module is used as a receiver RI HIGH Establish the call Hang up the call Idle Ring Figure 27 RI behaviour of voice calling as a receiver SIMS808 Hardware Design V1 02 38 2015 04 09 Smart Machine Smart Decision RI HIGH Establish the call Hang
33. ange of SIM808 15 from 3 4V to 4 4V Recommended voltage 15 4 0V The transmitting burst will cause voltage drop and the power supply must be able to provide sufficient current up to 2A For the VBAT input a decoupling capacitor low ESR such as a 100 uF is strongly recommended Increase 33PF and 10PF capacitors can effectively eliminate the high frequency interference A 5 1 V 500mW Zener diode is strongly recommended the diode can prevent chip from damaging by the voltage surge These capacitors and Zener diode should be placed as close as possible to SIM808 VBAT pins VBAT e e 10 1 42 1 T 500mW e e Figure 5 Reference circuit of the VBAT input Table 7 Recommended Zener diode Vendor Part number Power watts Packages 1 On semi MMSZ5231BT1G 500mW SOD123 p Prisemi PZ3D4V2H 500mW SOD323 3 Vishay MMSZ4689 V 500mW SOD123 4 Crownpo CDZSSCSVISM 500mW 0805 The following figure is the reference design of 5V input power supply The designed output for the power supply is 4 1V thus a linear regulator can be used SIMS808 Hardware Design V1 02 22 2015 04 09 Smart Machine Smart Decision DC INPUT U101 MIC29302 VBAT R103 101 C102 470R 100uF T C103 330uF PWR CTRL Figure 6 Reference circuit of the LDO power supply If there is a high drop out between the input and the desir
34. ase refer to document 1 A typical circuit of the PWM drives buzzer is shown in the following figure VBAT Q 4 7K i _ Module T 7 PWMO 47K Figure 44 Reference circuit of PWM drive buzzer SIMS808 Hardware Design V1 02 51 2015 04 09 Smart Machine Smart Decision Table 32 Buzzer output characteristics Working voltage 25 Working current 4 16 mA Note PWM pin must keep low when module in the boot process Table 33 PWM multiplex function PWMI PWMI GPIO2 PWM2 41 PWM2 GPIO3 Note Multiplexing function need different software version 4 17 Network Status Indication Table 34 Pin definition of the NETLIGHT NETLIGHT Network Status Indication The NETLIGHT pin can be used to drive a network status indication LED The status of this pin is listed in following table Table 35 Status of the NETLIGHT pin SIM808 is not running 64ms On 800ms Off SIM808 not registered the network 64ms On 3000ms Off SIM808 registered to the network 64ms 300ms Off PPP GPRS communication is established A reference ircuit is recommended in the following figure SIMS808 Hardware Design V1 02 52 2015 04 09 Smart Machine Smart Decision VBAT 4 NETLIGHTC e Figure 45 Reference circuit of NETLIGHT 4 18 Operating Status Indication The STATUS pin indicates the operating status of mod
35. ce to the minimal level In sleep mode the module can still receive paging message and SMS Software is active Module registered to the GSM network and the module is ready to communicate Connection between two subscribers is in progress In this case the power consumption depends on network settings such as DTX offon FR EFR HR hopping sequences antenna Module is ready for GPRS data transfer but no data is currently sent or received In this case power consumption depends on network settings and GPRS configuration There is GPRS data transfer PPP or TCP or UDP in progress In this case power consumption is related with network settings e g power control level uplink downlink data rates and GPRS configuration e g used multi slot settings The mode support charge function Default is not support Normal power off by sending the AT command AT CPOWD 1 or using the PWRKEY The power management unit shuts down the power supply for the baseband part of the Power off module and only the power supply for the RTC is remained Software is not active The serial port is not accessible Power supply connected to VBAT remains applied AT command AT CFUN can be used to set the module to a minimum functionality mode Minimum without removing the power supply In this mode the RF part of the module will not work or functionality the SIM card will not be accessible or both RF part and SIM card will be closed
36. d AT CFUN lt fun gt can be used to set SIM808 into minimum function When SIM808 is in sleep mode and minimum function mode the current of module is the lowest Note Customer must shut off the power supply of GPS and AT commands about the power saving mode can be executed correctly and the current consumption will be lower 4 3 1 Functionality Mode There are three functionality modes which could be set by the AT command AT CFUN lt fun gt The command provides the choice of the functionality levels lt fun gt 0 1 4 AT CFUN 0 minimum functionality AT CFUN I full functionality default AT CFUN 4 flight mode disable RF f nction Table 9 The current consumption of function modes AT CSCLK 1 Fun Current consumption mA 0 0 801 1 1 176 BS PA MFRMS 5 4 0 925 Minimum functionality mode minimizes the current consumption to the lowest level If SIM808 is set to minimum functionality by AT CFUN 0 the RF function and SIM card function will be disabled In this case the serial port is still accessible but all AT commands correlative with RF function and SIM card function will not be accessible For detailed information about the AT Command AT CFUN lt fun gt please refer to document 1 SIM808_Hardware Design_V1 02 29 2015 04 09 Smart Machine Smart Decision 4 3 2 Sleep Mode AT CSCLK 1 When the GPS function is shut off user can control SIM808 module to e
37. ecision 4 1 1 Power Supply Pin There are 3 VBAT pins Pin 4 5 6 used for power input and Pin 1 2 3 should be connected to the power GND VRTC pin is power supply of the RTC circuit in the module VDD EXT will output 2 8V when module is powered on and in normal operation When designing the power supply in user s application pay special attention to power losses Ensure that the input voltage never drop below 3 0V even when current consumption rises to 2A in the transmit burst If the power voltage drops below 3 0V the module may be shut down automatically The PCB traces from the VBAT pins to the power supply must be wide enough at least 80mil to decrease voltage drops in the transmit burst The power IC and the bypass capacitor should be placed to the module as close as possible VBAT MIN 3 0V ee Lt ed Figure 9 The minimal voltage requirement at drop 4 1 2 Monitoring Power Supply The AT command can be used to monitor the VBAT voltage For detail please refer to document 1 4 2 Power on off SIM808 4 2 1 Power on SIM808 SIM808 will be powered on in the following situations Power on SIM808 using the PWRKEY pin Power on SIM808 using the pin 4 2 1 1 Power on SIMS808 Using the PWRKEY Pin User can power on SIM808 by pulling down the PWRKEY pin for at least 1 second and release This pin is already pulled
38. ed output VBAT a DC DC power supply will be preferable because of its better efficiency especially with the 2A peak current in burst mode of the module The following figure is the reference circuit TNT 0101 LM2596 ADJ L101 FB101 VBAT 1 Vin 2 oe 100uH 270 OHM ON COR CD GE 2 FB 0102 Ph 6104 2n 1 TuF TY O0uF PWR CTRL 3 330uF 100nF MBR360 zs ee R102 e 1K Figure 7 Referenc circuit of the DC DC power supply The single 3 7V Li ion cell battery can be connected to SIM808 pins directly But the Ni Cd or Ni MH battery must be used carefully since their maximum voltage can rise over the absolute maximum voltage of the module and damage it Notes The module do not Support for charging Ni Cd or Ni MH battery When battery is used the total impedance between battery and VBAT pins should be less than 150mQ The following figure shows VBAT voltage drop at the maximum power transmit phase and the test condition is as following VBAT 4 0V VBAT bypass capacitor C 100uF tantalum capacitor ESR 0 7Q Another VBAT bypass capacitor Cg 1 uF 577uS_ 4 615mS gt 4 lvBAT VBAT Figure 8 VBAT voltage drop during transmit burst SIMS808 Hardware Design V1 02 23 2015 04 09 Smart Machine Smart D
39. eported and the module will be automatically powered off OVER VOLTAGE POWER DOWN At this moment AT commands can not be executed any more and only the RTC is still active Power off mode can also be indicated by STATUS pin which is at low level at this time 4 2 24 Over temperature or Under temperature Power off The module will constantly monitor the temperature of the module If the temperature gt 480 C the following URC will be reported 1 If the temperature 30 C the following URC will be reported 1 If the temperature gt 85 the following URC will be reported and the module will be automatically powered down CMTE 2 If the temperature lt 40 C the following URC will be reported and the module will be automatically powered down CMTE 2 8 808 Hardware Design V1 02 27 2015 04 09 Smart Machine Smart Decision At this moment AT commands can not be executed any more and only the RTC is still active Power off mode can also be indicated by STATUS pin which is at low level at this time Note Temperature detection is disabled by default the AT command could be used to read the temperature when the module is running For details please refer to document 1 4 2 3 Reset Function SIM808 also has RESET pin pin 16 used to reset the module This function is used as an emergency reset only when AT command AT CPOWD 1 and the PWRKEY pin has no effect User ca
40. far as possible 5 2 2 Power Supply Not only VBAT but also return GND are very important in layout The positive line of VBAT should be as short and wide as possible The correct flow from source to VBAT pin should go though Zener diode then huge capacitor Pin 1 Pin 2 and Pin 3 GND signals and shortest layout to GND of power source should be designed There are 15 GND pads in middle of module these pads could enhance the GND performances On the upper layer of these pads do not trace any signal if possible 5 2 3 SIM Card Interface SIM card holder will take large space on board and there is no anti EMI component inside Thus SIM card interface may be interfered please pay more attention on this interface during layout Ensure SIM card holder is far way from antenna or RF cable inside And it is better to put SIM card holder near the module as nearer as possible It is better to add ESD component to protect clock data reset and SIM VDD signals which should be far away from power and high speed frequency signal SIMS808 Hardware Design V1 02 59 2015 04 09 Smart Machine Smart Decision 5 2 4 Audio Interface In order to avoid TDD noise current noise or some other noise the signal trace of audio which is recommended to surrounded by ground should far away from antenna and power And do not let audio trace and VBAT trace parallel 5 2 5 Others It is better to trace signal lines of bunched as well as signals
41. gital cellular telecommunications Phase 2 AT command set for GSM Mobile Equipment ME 11 GSM 07 10 Support GSM 07 10 multiplexing protocol 10 GSM 07 07 Digital cellular telecommunications Phase 2 Use of Data Terminal Equipment Data Circuit terminating Equipment DTE DCE interface for Short Message Service SMS and Cell Broadcast Service CBS 12 GSM 07 05 Digital cellular telecommunications system Phase 2 13 GSM 11 14 Specification of the SIM Application Toolkit for the Subscriber Identity Module Mobile Equipment SIM ME interface Digital cellular telecommunications system Phase 2 14 GSM 11 11 Specification of the Subscriber Identity Module Mobile Equipment SIM ME interface 15 GSM 03 38 Digital cellular telecommunications system Phase 2 Alphabets and language specific information Digital cellular telecommunications system Phase 2 Mobile 16 GSM 11 10 Station MS conformance specification Part 1 Conformance specification SIM808_Hardware Design_V1 02 69 2015 04 09 HE Acompam Multiplexing Function E Smart Machine Smart Decision Table 55 Multiplexing function Pin name Reset Pin number Mode 0 default Mode 1 Mode 2 Mode 3 SIM_DET I PD 33 SIM DET SD DAT3 GPIO36 KBCO IPU 62 COLO GPIO16 IPU 61 COLI GPIO14 2 IPU 60 COL2 GPIO13 KBC3 IPU 59 COL3 GPIO12 KBRO I PD 58 ROWO GPIO21 I PD
42. gnal The switched off SIM808 of which VBAT pin voltage is greater than 3 4V will be automatically turned on when a charger is connected to VCHG pin SIMS808 Hardware Design V1 02 25 2015 04 09 Smart Machine Smart Decision lt t lt 8s gt STATUS lt Serial port Undefined Active Figure 13 Timing of power on module INPUT VDD EXP 4 2 2 Power off SIM808 SIM808 will be powered off in the following situations Normal power off procedure power off SIM808 by the PWRKEY pin Normal power off procedure power off 51 808 command AT CPOWD 1 Abnormal power off over voltage or under voltage automatic power off Abnormal power off over temperature or nder temperature automatic power off Note The VCHG pin should not be charged otherwise the module will not be powered off 4 2 2 1 Power off SIM808 by the PWRKEY Pin User can power off SIM808 by pulling down the PWRKEY pin for at least 1 second and release Please refer to the power on circuit The power off scenario is illustrated in following figure PWRKEY Le Is lt t lt 33s INPUT lt 0 7 VDD EXT 1 gt 2 06 lt d STATUS 2 0 Active Undefined Figure 14 Timing of power off SIM808 by PWRKEY SIM808_Hardware Design_V1 02 26 2015 04 09 Smart Machine Smart Decision This procedure makes the module log off
43. he battery voltage is less than 3 2V and more than 2 5V The battery is not suitable for fast charging when its condition is DDLO or UVLO The SIM808 provides a small constant current to the battery when the battery is between DDLO and UVLO In DDLO charging state SIM808 gives out pulse 70mA current to the battery And in UVLO charging state SIM808 provides about 200mA AC lt 7V or 70mA USB mode current to the battery DDLO charging terminates when the battery voltage reaches 2 5V UVLO charging terminates when the battery voltage is up to 3 2V Both DDLO and UVLO charge are controlled by the SIM808 hardware only Constant current mode CC As the battery voltage is charged up and over 3 4V the SIM808 will enter CC mode The typical CC mode charging current with AC adapter is 700mA and can be set from 70 to 800mA by the software Constant voltage mode CV and over voltage protection OV As the battery is charged up and over 4 1V the SIM808 will enter CV mode While theibatter voltage actually reaches 4 2V the charging current is gradually decreased step by step until stop charging 4 4 4 Operating Modes during Charging The battery can be charged during various operating mode That means that charging can be in progress while SIM808 15 in Normal mode SLEEP IDLE TALK GPRS IDLE or GPRS DATA mode In this case the voltage supply should be sufficient Here Charging in Normal mode is named as Charge mode If the charger is connected to
44. ine Smart Decision 6 4 SIM Card Interface Characteristics Table 42 SIM card interface characteristics 6 5 SIM VDD Characteristics Table 43 SIM_VDD characteristics QS 6 6 VDD EXT Characteristics Table 44 Von EXT rt X 6 7 Characteristics Table 45 characteristics SIM808_Hardware Design_V1 02 62 2015 04 09 HE Acompam VRTC OUT VRTC output voltage 2 2 V output current 2 0 mA E Smart Machine Smart Decision 6 8 Current Consumption VBAT 4V GPS engine is powered down Table 46 GSM current consumption Symbol Parameter Conditions Min Typ Max Unit VBAT Voltage 3 4 4 0 4 4 Voltage drop PCL 5 350 mV Voltage ripple f lt 200kHz 50 mV 200kHz 2 0 mV Average current Power off mode 134 150 uA Sleep mode AT CFUN 1 BS PA MFRMS 9 1 073 mA BS PA MFRMS 5 1 167 mA BS PA MFRMS 2 1 627 mA Idle mode AT CFUN 1 EGSM900 16 80 mA Voice call PCL 5 GSM850 216 6 mA EGSM900 22187 mA Voice call PCL 0 DCS1800 140 3 mA PCS1900 155 0 mA Data mode GPRS 1Rx 4Tx GSM850 445 5 mA EGSM900 433 7 mA DCS1800 287 1 mA PCS1900 296 5 mA Data mode GPRS 3Rx 2Tx GSM850 332 9 mA EGSM900 333 5 mA DCS1800 222 0 mA PCS1900 229 8 mA Data mode GPRS 4Rx 1Tx GSM850 222 6 mA EGSM900 224 7 mA DCS1800 158 4 mA PCS1900 165 2 mA Imax Peak c
45. interface only supports master mode data length is 16 bits linear and PCM clock rate is 256 KHz SIM808_Hardware Design_V1 02 45 2015 04 09 SIM Teoh Smart Machine Smart Decision Table 22 PCM pin specification Note User can use AT command control PCM interface for details please refer to document 1 4 10 1 PCM Interface lt Refer to the following figure for design PCM INO OP PCM OUTO con PCM_SYNCO ES YNC PCM CLKO PCMCLK GND GND Module SS CODEC PCM reference circuit 4 10 2 LCD Display SPI I SIM808 provides a s about embedded Tomi on please refer to document 1 Refer to PS figure for SPI design erface ace It could be used as SPI interface in the embedded AT application For details SIMS808 Hardware Design V1 02 46 2015 04 09 Smart Machine Smart Decision DISP_CSO OSPI CS DISP D CO OSPI D C DISP OSPI DISP DATAO OSPI DATA GNDO 7 LCD Figure 39 LCD reference circuit Note This function is not supported in the standard firmware If user wants this function firmware must be customized Please contact SIMCom for more details 4 11 SD Card Interface Refer to the following figure for SD card design DCD O O DAT2 SIM DET 04 gt DAT3 GP1019 gt CMD
46. ivity Time To First Fix TTFF and accuracy With a tiny configuration of 24 24 2 6mm SIM808 can meet almost all S5pace requirements in users applications such as M2M smart phone PDA tracker and other mobile devices SIM808 has 68 SMT pads which provide all hardware interfaces between the module and customers boards Support 4 4keypads by default One full modem serial port UART interface One USB which support debug and firmware upgrading Audio channels which include a microphone input and a receiver output One SIM card interface Charging interface Programmable general purpose input and output Support Bluetooth function Support GPS function Support two PWMs and two ADCs PCM SPI interface SIM808 is designed with power saving technique so that the current consumption is as low as 1 2mA in sleep mode with GPS engine powered down SIM808 integrates TCP IP protocol and extended TCP IP AT commands which are very useful for data transfer applications For details about TCP IP applications please refer to document 2 2 1 SIM808 Key Features Table 1 SIM808 GSM GPRS engine key features Feature Implementation Power supply 3 4V 4 4 Power saving Typical power consumption in sleep mode is 1 07 mA BS PA MFRMS 9 Charging Supports charging control for Li ion battery SIM808_Hardware Design_V1 02 11 2015 04 09 Frequency bands Transmitting power GPRS connectivity Temperature range
47. n Serial port supports the following baud rates 1200 2400 4800 9600 19200 38400 57600 115200 230400 and 460800bps Autobauding only supports the following baud rates 1200 2400 4800 9600 19200 38400 57600 and 115200bps The default setting is autobauding Autobauding allows SIM808 to automatically detect the baud rate of the host device Pay more attention to the following requirements SIMS808 Hardware Design V1 02 34 2015 04 09 Smart Machine Smart Decision Synchronization between DTE and DCE When DCE powers with autobauding enabled firstly user must send character or at to synchronize the baud rate It is recommended to send until DTE receives the response which means DTE and DCE are correctly synchronized For more information please refer to the AT command AT IPR Restrictions of autobauding operation The DTE serial port must be set at 8 data bits no parity and 1 stop bit The URC such as RDY CFUN 1 and CPIN READY will not be reported Note User can use AT command AT IPR x to set a fixed baud rate and the setting will be saved to non volatile flash memory automatically After the configuration is set as fixed baud rate the URC such as RDY CFUN I and CPIN READY will be reported when SIM808 is powered on 4 6 2 Serial Port The following figure shows the connection between module and client DTE
48. n pull the RESET pin to ground then the module will reset This is already isolated in the module so the external isolation is not necessary Following figure is internal circuit of the RESET pin RESET Circuit 1 8V 4 7K RESET Module Figure 15 Reset Circuit The typical value of RESET pin highlevel is 1 8V but with the isolated circuit inside even for the or 3 3V customer could use MCU s GPIO to driver this pin directly Resistor in serial the RESET signal could enhance the ESD performance but the value which should not be too high must be less than 100 Q Otherwise the level of RESET could be lower than threshold value RESET hardware parameters can refer to the following table Table 8 Electronic characteristic of the RESET Pin Pin name Symbol Min Typ Max Unit Vin 182 1 8 3 3 Vi 0 6 V pull down 105 mS The reset scenarios are illustrated in the following figure SIM808_Hardware Design_V1 02 28 2015 04 09 Smart Machine Smart Decision RESET lt t gt 105m6 gt Vin gt 2 7V IVi 0 6V t lt 400us VDD_EXT E VDD_EXT 2 8V Hold during reset P 2 7s STATUS EN T Figure 16 Reset timing sequence 4 3 Power Saving Mode SIM808 has two power saving modes functionality mode and sleep mode The AT command AT CSCLK 1 can be used to set SIM808 into sleep mode The AT comman
49. ne Cooling zone Standard temperature curve and the parameter range of lead free processes Figure 54 Typical Solder Reflow Profile Note Please refer to Module secondary 8MT UGD for more information about the module shipping and manufacturing SIMS808 Hardware Design V1 02 67 2015 04 09 Smart Machine Smart Decision 7 3 The Moisture Sensitivity Level The moisture sensitivity level of SIM808 is 3 The module should be mounted within 168 hours after unpacking in the environmental conditions of temperature lt 30 C and relative humidity of lt 60 RH It is necessary to bake the module if the above conditions are not met Table 52 Moisture classification level and floor life Level Floor Life out of bag at factory ambient 30 60 RH or as stated 1 Unlimited at lt 30 C 85 RH 2 1 year 2a 4 weeks 168 hours 4 72 hours 5 48 hours Sa 24 hours 6 Mandatory bake before use After bake it must be reflowed within the time limit specified on the label NOTES 1 If the vacuum package 15 not open for 6 months or longer than the packing date baking is also recommended before re flow soldering 2 For product handling storage processing IPC JEDEC J STD 033 must be followed 7 4 Baking Requirements SIM808 modules are vacuum packaged and guaranteed for 6 months storage without opening or leakage under the following conditions the environment temperature is lower than 40 C and the air humidity is less
50. nfo AT CGPSIPR Set GPS NMEA output UART bps For details of these AT command please refer to document 8 4 21 2 GPS Operating Modes GPS has two operating modes which can be controlled by AT command Active mode and Power down mode The following describes how to power on GPS and power down GPS 4 21 2 1 Power on GPS The GPS engine is controlled by GSM engine so when it is necessary to run GPS the GSM engine must be powered on and not in SLEEP mode User can power on GPS engine by sending AT command AT CGPSPWR 1 After powered on GPS is active as a GPS receiver The GPS engine will automatically acquire and track GPS satellites 4 21 2 2 Power down GPS The GPS engine will be set into power down mode by sending AT command AT CGPSPWR 0 In this mode the internal power supply for GPS will be shutdown and the current consumption is very low The last position c rrent time and ephemeris data will be stored in the GSM host memory 4 21 3 1PPS Output The 1PPS pin outputs pulse per second 1PPS pulse signal for precise timing purposes It will come out after successfully positioning The 1PPS signal can be provided through designated output pin for many external applications 4 22 Antenna Interface There are three antenna ports for SIM808 GSM antenna port named GSM_ANT Bluetooth antenna port named ANT and GPS antenna port named GPS ANT The RF interfaces of all the antenna ports have the impedance of 50Q
51. nter or exit the sleep mode AT CSCLK 1 by signal When is in high level and without interrupt on air and hardware such as interrupt or data in serial port SIM808 will enter sleep mode automatically In this mode SIM808 can still receive paging or SMS from network but the serial port is not accessible Note For SIM808 it requests to set AT command AT CSCLK 1 and ensure DTR at high level to enable the sleep mode the default value is 0 which can not make the module to enter sleep mode For more details please refer to document 1 4 33 Wake Up SIM808 from Sleep Mode AT CSCLK 1 When SIM808 is in sleep mode AT CSCLK 1 the following methods can wake up the module Pull down DTR pin The serial port will be active after DTR pin is pulled to low level for about 50ms Receive a voice or data call from network Receive a SMS from network Receive external interrupt Charge VCHG pin Note After module has received incoming call or new SMS serial port can report URC but the serial port not input AT command Only after the DTR pin is pulled tolow level for 50ms the serial port can input AT command 4 4 Charging Interface SIM808 has integrated a charging circuit inside the module for Li ion batteries charging control which make it very convenient for user s applications that support battery charging common connection is shown in the following figure Module Battery Pack
52. please refer to related antenna vendor s design recommendation The antenna vendor will offer further technical support and tune their antenna characteristic to achieve successful GPS reception SIMS808 Hardware Design V1 02 57 2015 04 09 Smart Machine Smart Decision performance The external antenna must be matched properly to achieve best performance so the matching circuit is necessary the connection is recommended as the following figure GPS E GND Matching circuit GPS ANT e e R101 GND C101 102 TSS e NEN Figure 50 GPS passive antenna matching circuit The components R101 C101 and C102 are used for antenna matching components value only can be got after the antenna tuning Normally R101 is 0 9 C101 and C102 are not mounted Active vvv Antenn VCC ANT es a R102 100 L101 27nH MODULE GND Matching circuit GPS ANT R101 e C101 C102 Figure 51 GPS active antenna matching circuit Active antennas have an integrated Low Noise Amplifier LNA VCC_ANT is needed customer s application board for the active antenna power input as shown in Figure 54 The inductor L101 is used to prevent the RF signal from leaking into the VCC_ANT pass and route the bias supply to the active antenna the recommended value of L101 15 no less than 27nH R102 c
53. re supported The SIM interface is powered from an internal regulator in the module 4 9 1 SIM Card Application Table 18 SIM pin definition Name Pin Function SIM VDD 29 Voltage supply for SIM card Support 1 8V or SIM card SIM DATA 30 SIM data input output SIM CLK 31 SIM clock SIM RST 32 SIM reset SIM DET 33 SIM card detection It is recommended to use an ESD protection component such as ON http onsemi com SMF12CTIG Note that the SIM peripheral circuit should be close to the SIM card socket The reference circuit of the 8 pin SIM card holder is illustrated in the following figure VDD EXT 4 7K MOLEX 91228 SIM VDD e e GND SIM BST RST VPP SIM OUR VO SIM DET e PRESENCE GND SIM DATA SIM Figure 34 Reference circuit of the 8 pin SIM card holder The SIM_DET pin is used for detection of the SIM card hot plug in User can select the 8 pin SIM card holder to 8 808 Hardware Design V1 02 42 2015 04 09 Smart Machine Smart Decision implement SIM card detection function AT command AT CSDT is used to enable or disable SIM card detection function For details of this AT command please refer to document 1 If the SIM card detection function is not used user can keep the SIM DET pin open The reference circuit of 6 pin SIM card holder is illustrated in
54. reme condition At DCS1800 and PCS1900 band the module is a class 1 device so the module s output power should not exceed 30dBm and at the maximum power level the output power tolerance should not exceed 2dB under normal condition and 2 5dB under extreme condition 6 10 2 Module RF Receive Sensitivity The following table shows the module s conducted receive sensitivity it is tested under static condition SIMS808 Hardware Design V1 02 65 2015 04 09 HE ee A company of SIM Tech Smart Machine Smart Decision Table 50 SIM808 conducted RF receive sensitivity GSM850 109dBm 107dBm EGSM900 109dBm 107dBm DCS1800 109dBm 107dBm PCS1900 109dBm 107dBm 6 10 3 Module Operating Frequencies The following table shows the module s operating frequency range it is followed by the 3GPP TS 05 05 technical specification requirement Table 51 SIM808 operating frequencies GSM850 869 894MHz 824 849 MHz EGSM900 925 960MHz 880 915 2 DCS1800 1805 1880MHz 1710 1785MHz PCS1900 1930 1990MHz 1850 1910MHz SIMS808 Hardware Design_V1 02 66 2015 04 09 Smart Machine Smart Decision 7 Manufacturing 7 1 Top and Bottom View of SIM808 52 1 8680 SN ELBE 13521670464 EUH Figure 53 Top and Bottom View of SIM808 7 2 Typical Solder Reflow Profile Standard temperature curve and parameter rangee 150 210 amjvaadura 70 120 Sec Preheat zone Soak 2 Reflow zo
55. s s MODULE be accorded to differential close as possible signal layout rules The lines in bold type should SPKIN Figure 31 Speaker reference circuit These components should be placed to speaker as close as possible MODULE The lines in bold type should be accorded to differential signal layout rules B 10pF i Amplifier SPK1P Circuit 10pF Figure 32 Speaker with amplifier reference circuit 8 808 Hardware Design V1 02 40 2015 04 09 Smart Machine Smart Decision 4 8 2 Microphone Interfaces Configuration These components should be placed 1 microphone as close as possible 1 1 The lines in bold type should be accorded to differential signal layout rules MODULE oa Microphone 33pF 10pF Figure 33 Microphone reference circuit 4 8 3 Audio Electronic Characteristics Table 16 Microphone input characteristics Mic biasing voltage Working Current 2 mA Input impedance differential 13 20 27 KO Idle channel noise 67 dBm Input level 40dBm0 29 dB SINAD Input level 0dBm0 69 dB Table 17 Audio output characteristics Normal output 32 Q receiver 4 84 TDD GSM signal could interfere with audio by coupling or conduc
56. s Ltd 2015 SIM808_Hardware Design_V1 02 2 2015 04 09 Smart Machine Smart Decision Contents 3 Version HIStory 10 1 Introduction R N O A 11 2 SIMSO08 Overview 11 2 1 SIM808 Key Features 11 2 2 Operating MOd s oerte eet ERN NE nee cte 15 2 3 51 808 Functional 16 3 Package Information csccssssssscsscsssssscsssssssssssscescesssssesscesssssssssssssssssscsssssossscssescoseecdassessossbassessossonseness 17 3 1 Pin Dia Sarna Wc i INS 17 3 2 Pan DescHponc ere ot 18 3 3 Package Ditrienstons ac tema oaa en 20 4 Application Inter ETUR 22 4 1 Power SUPP 22 4 1 1 PowerSupply Pin etae ea 23 4 12 Monitoring Power Supply Miserere 24 4 2 Power on down SIM808 eee E N 24 421 Poweron SIMSUS ener teen op tie ete Den bere dde 24 422 Power down SIMSOS esee 26 4 2 3 Reset rennen nnne nenne teniente 27 4 3 Power Saving Mode usce Ne eese ELCHE ERI 28 434 Functonality Mode iui ANN E tea tuae Fus nsa su Fe rene aie e 29 432 Sleep Mode AT CSCLKRAD
57. there are no sources on the VBAT or VCHG pins which means the module is only supplies by the external VRTC the system time will not be accurate SIM808_Hardware Design_V1 02 33 2015 04 09 m company of SIM Tech 4 6 Serial Port and USB Interface Smart Machine Smart Decision SIM808 provides one unbalanced asynchronous serial port The module is designed as a DCE Data Communication Equipment The following figure shows the connection between module and client DTE Name Pin number Function 9 Data terminal ready RI 10 Ring indicator DCD 11 Data carrier detect Serial port CTS 12 Clear to send RTS 13 Request to send TXD 14 Transmit data RXD 15 Receive data aise VCHG 25 VCHG power supply ere USB DP 26 USB data line positive USB DN 2 USB data line negative Table 11 Serial port and USB pin definition Note Hardware flow control is disabled by default The AT command A T IFC 2 2 can enable hardware flow control The AT command AT IFC 0 0 can disable hardware flow control For more details please refer to document 1 Table 12 Serial port characteristics Symbol Min Typ Max Unit Vit 0 3 0 7 V Vin 21 3 1 VoL 0 4 V 2 4 2 8 4 6 1 Function of Serial Port Serial port Full modem device Contains data lines TXD and RXD hardware flow control lines RTS and CTS status lines DTR DCD and RI Serial port can be used for CSD FAX GPRS service and AT communicatio
58. ting Coupling noise could be filtered by adding 33 pF and 10pF capacitor over audio lines 33pF capacitor could eliminate noise from GSM900MHz while 10pF capacitor could eliminate noise from DCS1800MHz frequency Coupling noise has great relatives with PCB layout Under some scenarios TDD noise from GSM 900MHz frequency affects heavily but some different story is from GSM1800MHz fervency so customer should develop this filter solution according to field test result GSM antenna is the key coupling interfering source of TDD noise Pay attention to the layout of audio lines which should be far away from RF cable amp antenna and VBAT pin The bypass capacitor for filtering should be placed near module and another group placed near to connector SIMS808 Hardware Design_V1 02 41 2015 04 09 Smart Machine Smart Decision Conducting noise is mainly caused by the VBAT drop If Audio PA was powered by VBAT directly then there will be some cheep noise from SPK output easily So it s better to put big capacitor and ferrite bead near audio PA input TDD noise has something to do with GND signal surely If GND signal is not well treated lots of high frequency noise will interfere with MIC and speaker over bypass capacitor So take good care of GND during PCB layout 4 9 SIM Card Interface The SIM interface complies with the GSM Phase specification and the new GSM Phase 2 specification for FAST 64 kbps SIM card Both 1 8V and 3 0V SIM card a
59. ule The pin o tput high when module power on output is low when module powered off Table 36 Pin definition of the STATUS STATUS Operating status indication 4 19 RF Synchronization Signal The synchronization signal setves to indicate growing power consumption during the transmit burst Table 37 Definition of the RE SYNC pin RF SYNC Transmit synchronization signal Note Donot pull up RF SYNC The timing of the synchronization signal is shown in the following figure High level of the RF SYNC signal indicates increased power consumption during transmission SIMS808 Hardware Design V1 02 53 2015 04 09 Smart Machine Smart Decision 220us 577us Transmit burst RF_SYNC Figure 46 RF_SYNC signal during transmit burst 4 20 Bluetooth SIM808 supports Bluetooth function customer only needs to design the Bluetooth antenna and then customer can operate Bluetooth conveniently by AT commands As module solution SIM808 provides series of AT interface to operate Bluetooth function including pairing bonding pushing or receiving file Also including interface for SPP service which could communicate between Bluetooth device and others via serial port When the module as a Bluetooth headset role we provide a set of AT commands to control the remote smart phones such as phone calls turn on or hang up calls and so on For the detail commands about Bluetooth please refer to document 9
60. unction need different software version 4 14 General Purpose Input Output GPIO SIM808 provides 2 GPIO pins The output voltage level of the GPIO can be set by the AT command AT SGPIO The input voltage level of the GPIO can also be read bythe command SGPIO For more details please refer to document 1 Table 28 Pin definition of the GPIO GPIO17 GPIO19 43 GPIO19 GPIO17 Figure 43 GPIO timing sequences SIMS808 Hardware Design_V1 02 50 2015 04 09 Smart Machine Smart Decision 4 15 ADC Table 29 Pin definition of the ADC ADCO Analog to Digital Converter ADCI 24 Analog to Digital Converter SIM808 provides two auxiliary ADC which can be used to measure the voltage User can use AT command to read the voltage value For details of this AT command please refer to document 1 Table 30 ADC specification Voltage range ADC Resolution 10 bits Sampling rate 1 0833 MHz ADC precision 10 30 mV Note The voltage should be less than 2 8V or the ADC may be damaged 4 16 PWM Table 31 Pin definition of the PWM PWMI 42 PWM1 multiplex with GPIO2 PWM2 41 PWM2 multiplex with GPIO3 PWM output frequency varies from 200Hz to 100KHz Two 7 bit unsigned binary parameters are used for the output period and for the duty cycle AT command SPWM is used to set the output period and duty cycle of the PWM For details ple
61. up the call LOW cse eee eiie Idle Ring Figure 28 RI behaviour of data calling as a receiver HIGH i 120ms LOW RES Idle Receive SMS URC Figure 29 RI behaviour of URC or receive SMS However if the module is used as caller the RI will remain high Please refer to the following figure HIGH Idle Ring Establish Hang up Idle the call the call Figure 30 RI behaviour as a caller 4 8 Audio Interfaces SIM808 provides one analog input which could be used for electret microphone The module also provides one analog output which can directly drive 320 receiver Table 15 Audio interface definition Pin name Pin number Function MICIP 19 Main Audio input positive Audio MICIN 20 Main Audio input negative channel SPKIP 21 Main Audio output positive SPKIN 22 Audio output negative 8 808 Hardware Design V1 02 39 2015 04 09 A company of SIM Teoh Smart Machine Smart Decision AT CMIC is used to adjust the input gain level of microphone AT SIDET is used to set the side tone level In addition AT CLVL is used to adjust the output gain level For more details please refer to document 1 In order to improve audio performance the following reference circuits are recommended The audio signals have to be layout according to differential signal layout rules as shown in following figures 4 8 1 Speaker Interface Configuration These components should be placed to speaker a
62. up to VBAT in the module internal so external pull up is not necessary Reference circuit is shown as below VBAT 100K PWRKEY Power TX on down logic 4 7K Turn on off impulse 47K Module Figure 10 Powered on down module using transistor SIM808_Hardware Design_V1 02 24 2015 04 09 Smart Machine Smart Decision VBAT 100K PWRKEY Power O on down logic Module Figure 11 Powered on down module using button The power on scenarios is illustrated as following figure t gt 1 5s gt VBAT _ 1 1 gt 15 4 gt PWRKEY lt 0 7 INPUT t VDD_EXT a t gt 3s To STATUS Serial port Undefined Active Figure 12 Timing of power on module When power on procedure is completed SIM808 will send following URC to indicate that the module is ready to operate at fixed baud rate RDY This URC does not appear until autobauding function is active Note User can use command AT IPR x to set a fixed baud rate and save the configuration to non volatile flash memory After the configuration is saved as fixed baud rate the Code should be received from the serial port every time when SIM808 is powered on For details please refer to the chapter document 1 4 2 1 Power on the SIM808 using the VCHG Si
63. urrent 1 0C for continuous discharging mode Discharge Cut off Voltage 3 0V cell Internal resistance Initial lt 150mQ 4 4 5 Implemented Charging Technique SIM808 has battery charging function but charging function is not supported by default the customer should input AT command AT echarge 1 to enable charging function There are two pins related to the battery charging function VCHG The VCHG Pin is driven by an external voltage AC adapter or USB host System can use this pin to detect a charger supply and the external voltage provides most charging current through SIM808 module to battery when charging is in fast charge state VBAT pin gives charging current to external battery from SIM808 module It is very simple to implement charging function user just needs to connect the charger to the VCHG Pin and connect the battery to the VBAT Pin SIM808 battery charging happens after detecting charger supply and the presence of battery If there is no charger supply or no battery present charging function will not be enabled Normally there are three states in the whole charging procedure DDLO charge Pull up mode and UVLO charge Pre charge mode Constant current mode Constant voltage mode and over voltage protection OV SIM808_Hardware Design_V1 02 31 2015 04 09 Smart Machine Smart Decision DDLO charge and UVLO charge DDLO 15 the state of battery when its voltage is under 2 5V And UVLO means t
64. urrent During TX burst 2 0 A In above table the current consumption value is the typical one of the module tested in laboratory In the mass production stage there may be differences among each individual SIM808_Hardware Design_V1 02 63 2015 04 09 Smart Machine Smart Decision 6 0 Electro Static Discharge SIMS808 is an ESD sensitive component so more attention should be paid to the procedure of handling and packaging The ESD test results are shown in the following table Table 47 The ESD characteristics Temperature 25 C Humidity 45 Note It is suggested that customers in serials with 100 resistances on ey for ESD consideration 6 10 Radio Characteristics S 6 10 1 Module RF Output Power S The following table shows the module conducte sm er it is followed by the 3GPP TS 05 05 technical specification requirement Table 48 SIM808 GSM 900 and GS nducted RF output power 64 2015 04 09 Smart Machine Smart Decision company of SIM Tech Table 49 SIM808 DCS 1800 and PCS 1900 conducted RF output power E 8 gt 8 un wer the following should be noted At GS 0 ani M850 band the module is a class 4 device so the module s output power should not exceed 33dBm and at the maximum power level the output power tolerance should not exceed 2dB under normal condition and 2 5dB under ext
65. with status and control lines unbalanced asynchronous 1200bps to 460800bps Can be used for sending AT commands or transmitting data stream Support RTS CTS hardware handshake and software ON OFF flow control Multiplex ability according to GSM 07 10 Multiplexer Protocol Autobauding supports baud rate from 1200 bps to 115200bps USB interface Can be used for debugging and firmware upgrading Support phonebook types SM FD LD RC ON MC GSM 11 14 Release 99 Support RTC Can be set by AT command Size 24 24 2 6mm 12 2015 04 09 1 50 24hr static 130dBm 2 50 17 3 GPS si level 130dBm 4 Single Power supply 3 8V 130dBm GSM IDLE Table 3 BT engine Performance SIMS808 Hardware Design V1 02 Smart Machine Smart Decision 2015 04 09 n Com Perens deu put Smart Machine Smart Decision SIM808_Hardware Design V1 02 14 2015 04 09 m company of SIM Tech 2 2 Operating Modes Smart Machine Smart Decision The table below summarizes the various operating modes of SIM808 Table 5 Overview of operating modes Mode Function GSM GPRS SLEEP GSM IDLE Normal GSM operation TALK GPRS STANDBY GPRS DATA Charge Module will automatically go into sleep mode if the conditions of sleep mode are enabling and there is no on air and no hardware interrupt such as GPIO interrupt or data on serial port In this case the current consumption of module will redu

SIM808_Hardware Design_V1.02

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