取扱説明書
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1. O IRQ O GND Cx y c Q A Q Q eo lt lt Z I2CL I2CD CS SCL MISO MOSI SINT ADDO ADD1 VDD VREG EN VREG Yr 10pF 24V 55V L1 6 3V e Ul wa 100 u H VDD W Figure 2 i C 1 R 1 Exposed pad 680pF 10kO 25V C2 270pF 25V HEEL mE VDD VREG EN_VREG R3 R2 TuE Tp 10kO 10kO 3V 6 3V Figure 5 Absolute Maximum Ratings Electrical System Specifications Figure 10 Parameter Max Comments Symbol Parameter Min Typ Max Units Note Electrical Parameters Input Characteristic VDD DC supply voltage 0 5 7 V Rin Input AC impedance 200 kQ VIN Input pin voltage 0 5 5 V Current Consumption Input current latch up P d twh ower down current when scr immunit2. Ox3B SRCO CALIB NOK 6 R 0 Calibration of SRCO unsuccessful http akizukidenshi com catalog g gK 08685 mido 1 not successful Figure xx ams Datasheet Confidential 2014 Jan 1 03 5 0 m aiar ER 2015_02_24 rev Figure 31 I C Timing Diagram start Pius Figure 32 Conditions Figure 33 TsP Spike intensity 50 100 ns Tu High Clock Time 330 m Slave AS3935 as receiver EJ Slave AS3935 as transmitter 400 kHz Clock speed TLO Low Clock Time 660 ns 2 1 I2CD has to change Tsetup l C Page Write Figure 34 before rising edge I2CL L Slave AS3935 as receiver WA WAt WA Slave AS3935 as transmitter No hold time needed for 12CD relative to rising edge of 12CL Within start condition after low going I2CD 12CL has to THDISTA stay constant for specified hold time 309 s FC Page Read Figure 36 TSU STO After high going edge of I2CL I2CD has to stay constant 100 ns TSU STA start condition is applied 100 ns Slave AS3935 as receiver WA WA WAt Slave AS3935 as transmitter PC Abbrev
3. Connect the LCO to the IRQ pin setting register REGOx08 7 1 Select the division ratio of the LCO frequency defined in register REGOx03 7 6 Based on the division ratio the theoretical period can be calculated Wait 2ms for the LCO to start up and to be settled before measuring the frequency Tuning Capacitor Block Diagram AS3935 500kHz IRQ LCO INN REGOx08 3 O 0 120pF 8pF x 16 steps AS3935 AN05 Detailed Description The AS3935 can detect the presence of an approaching storm with lightning activities and provide an estimation of the distance to the leading edge of the storm where the leading edge of the storm is defined as the minimum distance from the sensor to the closest edge of the storm The embedded hardwired distance estimation algorithm of the AS3935 issues an interrupt on the IRQ pin see Interrupt Management on page 34 every time a lightning is detected The estimated distance which is displayed in the distance estimation register does not represent the distance to the single lightning but the estimated distance to the leading edge of the storm A graphical representation is shown in the Figure 17 Figure 17 Storm xX e c C 2 Cc O v E LLI x Single lightning events Distance estimation of the AS3935 Lightning Algorithm Z amp 317 3U A The
4. lightning algorithm consists of hardwired logic False events man made disturbers which might trigger the AS3935 are rejected while lightning events initiate calculations to estimate the distance to the head of the storm The Lightning algorithm is broken up into three sub blocks 1 Signal validation Verification that the incoming signal can be classified as lightning 2 Energy calculation Calculation of the energy of the single event 3 Statistical distance estimation According to the number of stored events lightning a distance estimate is calculated In case the incoming signal does not have the shape characteristic to lightning the signal validation fails and the event is classified as disturber In that case the energy calculation and statistical distance estimation are not performed and the sensor automatically goes backto listening mode The shortest time span between two lightning strikes that the AS3935 can resolve is approximately one second Once a signal is classified as disturber the sensor is deactivated for a further 1 5s time period As the duration of disturber signals can vary this sensor down time will prevent the sensor from triggering repeatedly due to longer disturber events Signal Validation During the signal validation phase the shape of the incoming signalis analyzed The sensor can differentiate between signals that show the pattern characteristic of lightning strikes and man
5. 0 1 0 Outdoor 01110 1100 78 0 1 1 1140 95 1 0 0 Analog Front end AFE and Watchdog withintheantenna s bandwidth This is achieved by making the AFE bandwidth greater than the antenna bandwidth 1570 112 1 0 1 The AFE amplifies and demodulates the AC signal picked up by The AFE gain has been optimized for two operating the antenna The AS3935 is based on narrowband receiving environments as shown in Figure 38 By default the gain is set 1800 130 1 1 0 techniques with a center frequency of 500 kHz and a bandwidth to Indoor It is of paramount importance that the gain is set Sob ia i i of about 33 kHz The AFE gain can be considered as constant according to the surrounding environment otherwise the sensor will not yield the desired results Frequency Division Ratio for the Antenna Tuning Division Ratio REG0x03 7 REGOx03 6 16 0 0 32 0 1 64 1 0 128 1 1 Figure 45 The antenna tuning algorithm can be performed in the following way 1 Measure actual resonance frequency of the antenna on the IRQ pin 2 Add additional internal capacitance in parallel to the external LC 3 Repeat this sequence until the resonance frequency is tuned to 500 kHz Measure LCO Frequency LCO
6. C on r3 I2C Bus 10kO R3 S I2C Bus Us D 10kO R2 U A amp H S z BRIS KEF PCNATSY FEF uj 2 4V 5 5V AE AS3935 5 X AS3935 12C 0000000 00h 0x00 EGO EE ESHER PIFF sem TF TORDERA un SCL XS W Franklin i es haf calil BJERE HAV CEGSGVN SDA 1x5 UL OSDA Arduino O SCL
7. bration time for the RC 2 im the RC oscillators DD voltage oscillators starts after the 9 In case the voltage regulator is OFF 2 4 3 6 V LCO settles Ambient Voltage Regulator T i o AMB temperature 5 9p E j VRour E regulator output 27 30 33 V CMOS Input CMOS Figure 7 RE Parameter Detailed Register Map Figure 23 V High level input voltage 0 6 VDD 0 7 VDD 0 9 VDD V m 3 3 Address Register Name Bit Type erates Description ViL Low level input voltage 0 125 VDD 0 2 VDD 0 3 VDD V Reserved 7 6 0 Reserved Note On ALL outputs use the cells with the smallest drive capability which will do the job in order to prevent current spikes problems 0x00 AFE GB 5 1 R W 10010 AFE Gain Boost CMOS Output CMOS Figure 8 PWD 0 0 Power down Parameter Conditions Min Typ Max Units NF_LEV 6 4 010 Noise Floor Level High level output 0x01 R W VoH K ge VDD 0 4 V WDTH 3 0 0010 Watchdog threshold With a load current of 1mA VoL Low level output voltage VSS 0 4 V Reserved 7 1 Reserved Ense cdocktregueticyof CL STAT 6 1 Clear statistics CL Capacitive load o y 400 pF 0x02 R W 1MHz MIN_NUM_LIGH 5 4 00 Minimum number of lightning SREJ 3 0 0010 Spike rejection Tristate CMOS Output 3 CMOS Figure 9 pr F Frequency division ration for antenna Parameter Conditions Min Typ Max LCO_FDIV 7 6 00 tuning R W V i 0 Mask D OH High level output voltage With a load c
8. f _ AS3935 I2C Bus ITI ens AS3935 AMS IRQ IRO 254mm 5 SIP AS3935 IZC IRO 2 4V 55V VDp 5V 70uA 350 UA 2C 40km AFE 32 NF 8 WDTH 16 12
9. iations 12C Figure 35 Symbol Description Distance Estimation Figure 42 S START condition after STOP REG0x07 5 0 Distance km Sr Repeated START 111111 Out of range DW Device Address for write 101000 40 DR Device Address for read 100101 37 WA Word address 100010 34 A Acknowledge 011111 31 N No acknowledge 011011 27 P STOP condition 011000 24 WA Internal address increment 010100 20 010001 17 Registers 0x3C 0x3D Figure 37 001110 14 PRESET DEFAULT 0x3C oe ii CALIB_RCO 0x3D poe i 000110 6 000101 5 Interrupts Figure 43 000001 Storm is Overhead Interrupt Name REGO0x03 3 0 Description INT_NH 0001 Noise level too high Minimum Number of Lightning Detection Figure 44 INT D 0100 Disturber detected Minimum Number of Lightning REGOx02 5 REGOx02 4 INT_L 1000 Lightning interrupt 1 0 0 5 0 1 Settings for the Noise Floor Threshold 7 amp 7 17 RENDRE Figure 40 9 1 0 Continuous Input Continuous Input 16 1 1 Noise Level Noise Level REG0x01 6 REGOx01 5 REGOx01 4 LVrms Outdoor LVrms Indoor AFE Setting Outdoorvs Indoor AFE Figure 38 390 28 0 0 0 630 45 0 0 1 Indoor 10010 860 62
10. made disturbers such as random impulses Besides the watchdog threshold the spike rejection settings SREJ in REGOxO2 3 0 can be used to increase the robustness against false alarms from such disturbers By default the value is set to REGOxO2 3 0 0010 Larger values in REGOxO2 3 0 correspond to more robust disturber rejection yet with the drawback of a decrease in detection efficiency In Figure 41 the detection efficiency is illustrated as function of distance for various settings of SREJ At the end of the signal verification the AS3935 automatically returns to listening mode Energy Calculation If the received signal is classified as lightning the energy is calculated The result of the energy calculation is then stored in the registers REGOx06 4 0 REGOx05 7 0 and REGOx04 7 0 This value is just a pure number and has no physical meaning Detection Efficiencies vs Distance for Different Setting of SREJ if WOTH 0001 60 Figure 41 40 20 Detection Efficiency 96 0 0 Radius km
11. urrent of VDD 0 4 V 0x03 MASK DIST 5 0 ask Disturber VoL Low level output voltage finn VSS 0 4 V Reserved 4 0 Reserved IOZ Tristate leakage current To Vpp and Vss 400 amp INT 3 0 R 0000 Interrupt see Figure 43 0x04 S LIG L 7 0 R 00000000 Energy ofthe Single Lightning LSBYTE 0x05 S LIG M 7 0 R 00000000 Energy of the Single Lightning MSBYTE Register Table Figure 22 Reserved 7 5 Reserved Register 0x06 Ener i ightni gy of the Single Lightning S LIG MM 4 0 R 00000 MMSBYTE 0x00 Reserved AFE GB PWD Reserved 7 6 Reserved 0x01 Reserved NF LEV WDTH 0x07 DISTANCE 5 0 R 000000 Distance estimation 0x02 Reserved CL STAT MIN NUM LIGH SREJ DISP LCO 7 0 Display LCO on IRQ pin 0x03 LCO FDIV MASK DIST Reserved INT DISP SRCO 6 0 Display SRCO on IRQ pin 0x04 S LIG L 0x08 pisp TRCO Br 0 Display TRCO on IRQ pin 0x05 S LIG M 7 Internal Tuning Capacitors from 0 to TUN_CAP 3 0 0000 j 0x06 Reserved S _LIG MM m 3 0 120pF in steps of 8pF 0x07 Reserved DISTANCE TRCO CALIB DONE 7 R 0 Calibration of TRCO done 1 successful 0x08 DISP LCO DISP SRCO DISP TRCO Reserved TUN CAP OGA TRCO CALIB NOK 6 R 0 Calibration of TRCO unsuccessful x 1 not successful 0x3A TRCO_CALIB_DONE TRCO_CALIB_NOK Reserved Reserved 5 0 R 000000 Reserved 0x3B SRCO_CALIB_DONE SRCO_CALIB_NOK Reserved SRCO_CALIB_DONE 7 R 0 Calibration of SRCO done 1 successful
12. y 100 100 mA Norm Jedec 78 lpWDROFF RE 1 2 uA Electrostatic Discharge Power down current when IPWORON VREG is ON iB E Norm MIL 883 E method ESD Electrostatic discharge 2 kV 3 3015 Human Body Model Current consumption in ILSMROFF listening mode when VREG is 60 80 pA Continuous Power Dissipation OFF Total power dissipation Current consumption in Pt all supplies and 0 1 mW ILsMRoN listening mode when VREG is 70 pA outputs ON Temperature Ranges and Storage Conditions Current Consumption in signal 350 A SYM verification mode Tstrg Storage temperature 65 150 et Timing Norm IPC JEDEC J STD 020 The reflow peak soldering Duration in signal verification temperature body T ghtning mode once lightning is 1 s temperature is specified detected Ti boeing 260 eC according IPC JEDEC J STD 020 Sasa P Moisture Reflow Sensitivity T REA m 2 beni cation T Classification for Non hermetic disturber de i Isturber Is i gt Solid State Surface Mount eee Devices Oscillators Humidity l 5 85 Time needed by non condensing LCOsur LCO Start up Time 2 ms the LCO to MSL Moisture Sensitivity 3 Represents a maximum floor life idi Level time of 168h Teed 2 after 1065 1 125 1 19 MHz calibration Assuming T a FLCO 500 kHz Operating Conditions Figure 6 Tuc rc amas after 305 3226 340 kHz Symbol Parameter Conditions Typ Max Units The calibration of j Positive supply In case the voltage regulator is ON 2 4 5 5 V TRCOCAL Cali
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