TPA3008D2: 10-W Stereo Class-D Audio Power
Contents
1. IF Seating Plane ba 0 08 4146927 B 08 03 NOTES A All linear dimensions are in millimeters B This drawing is subject to change without notice C Body dimensions do not include mold flash or protrusion D This package is designed to be soldered to a thermal pad on the board Refer to Technical Brief PowerPad Thermally Enhanced Package Texas Instruments Literature No SLMA002 for information regarding recommended board layout This document is available at www ti com lt http www ti com gt E Falls within MS 026 PowerPAD is a trademark of Texas Instruments 435 TEXAS INSTRUMENTS www ti com THERMAL PAD MECHANICAL DATA PHP S PQFP 648 PowerPAD PLASTIC QUAD FLATPACK THERMAL INFORMATION This PowerPAD package incorporates an exposed thermal pad that is designed to be attached to a printed circuit board PCB The thermal pad must be soldered directly to the PCB After soldering the PCB can be used as a heatsink In addition through the use of thermal vias the thermal pad can be attached directly to the appropriate copper plane shown in the electrical schematic for the device or alternatively can be attached to a special heatsink structure designed into the PCB This design optimizes the heat transfer from the integrated circuit IC For additional information2. Output power vs Supply voltage 8 9 Efficiency vs Output power 10 Efficiency vs Total output power 11 Voc Supply current vs Total output power 12 Crosstalk vs Frequency 13 KsvR Supply ripple rejection ratio vs Frequency 14 CMRR Commom mode rejection ratio vs Frequency 15 TOTAL HARMONIC DISTORTION NOISE TOTAL HARMONIC DISTORTION NOISE vs vs FREQUENCY FREQUENCY 10 0 10 9 Vcc 18 V 1 Vcc 12 V Ri 2160 9 Po 16 Q 2 Gain 21 6 dB E a 21 Gain 21 6 dB z c c o 1 5 2 2 a o 2 5 5 2 Po 0 5W 0 1 s 3 Po 1W e E z T t a Po 1W a 0 01 m Po 0 5 W 2 5 W 0 005 0 01 20 100 1k 10k 20k 20 100 1k 10k 20k f Frequency Hz f Frequency Hz Figure 1 Figure 2 Copyright 2004 2010 Texas Instruments Incorporated Submit Documentation Feedback 7 Product Folder Link s TPA3008D2 TEXAS TPA3008D2 INSTRUMENTS SLOS435C MAY 2004 REVISED AUGUST 2010 www ti com TOTAL HARMONIC DISTORTION NOISE TOTAL HARMONIC DISTORTI
3. d peel ov internally connected to pins 46 and 47 PVCCR 46 47 _ PAM internally connected to pins 38 and 39 RINP 3 l Positive audio input for right channel RINN 2 l Negative audio input for right channel ROSC 27 y o I O current setting resistor for ramp generator ROUTN 44 45 Class D 1 2 H bridge negative output for right channel ROUTP 40 41 Class D 1 2 H bridge positive output for right channel SHUTDOWN 1 low shutdown high operational TTL logic levels with VCLAMPL 25 Internally generated voltage supply for left channel bootstrap capacitors VCLAMPR 36 Internally generated voltage supply for right channel bootstrap capacitors V2P5 4 2 5 V Reference for analog cells Thermal Pad _ _ Pn a icd d the center point for both grounds Internal TYPICAL CHARACTERISTICS Table 1 TABLE OF GRAPHS FIGURE THD N Total harmonic distortion noise vs Frequency 1 2 3 4 THD N Total harmonic distortion noise vs Output power 5 6 Closed loop response 7 6 Submit Documentation Feedback Copyright 2004 2010 Texas Instruments Incorporated Product Folder Link s TPA3008D2 up TEXAS TPA3008D2 INSTRUMENTS www ti com SLOS435C MAY 2004 REVISED AUGUST 2010 TYPICAL CHARACTERISTICS continued Table 1 TABLE OF GRAPHS continued
4. Power represented by dashed line may require external heatsinking 8 9 10 11 12 13 14 Vcc Supply Voltage V Figure 9 Copyright 2004 2010 Texas Instruments Incorporated Product Folder Link s Phase Po Output Power W N WO Q O N O O o 100 90 80 70 60 50 40 Efficiency 96 30 20 10 TPA3008D2 SLOS435C MAY 2004 REVISED AUGUST 2010 OUTPUT POWER vs SUPPLY VOLTAGE THD N 10 THD N 1 9 10 11 12 13 14 15 16 17 18 Vcc Supply Voltage V Figure 8 EFFICIENCY vs OUTPUT POWER Vcc 18 V RL 16Q 0 1 2 3 4 5 6 7 8 9 10 Po Output Power Per Channel W Figure 10 Submit Documentation Feedback 9 TPA3008D2 TPA3008D2 SLOS435C MAY 2004 REVISED AUGUST 2010 10 Efficiency Crosstalk dB EFFICIENCY vs TOTAL OUTPUT POWER 100 90 80 70 60 50 40 Vec 12 V LC Filter Resistive Load Stereo Operation 012 3 4 5 6 7 8 9 Po Total Output Power W 10 11 12 Figure 11 CROSSTALK vs FREQUENCY Vec 12 V Po 2 5 W Gain 21 6 dB RL 289 100 1k f Frequency Hz 10k 2
5. 4 Note that these calculations are for the worst case condition of 8 5 W delivered to the speaker Because the 0 35 W is only 4 of the power delivered to the speaker it may be concluded that the amount of power actually dissipated in the speaker is relatively insignificant Furthermore this power dissipated is well within the specifications of most loudspeaker drivers in a system as the power rating is typically selected to handle the power generated from a clipping waveform When to Use an Output Filter for EMI Suppression Design the TPA3008D2 without the filter if the traces from amplifier to speaker are short 50 cm Powered speakers where the speaker is in the same enclosure as the amplifier is a typical application for class D without a filter Most applications require a ferrite bead filter The ferrite filter reduces EMI around 1 MHz and higher FCC and CE only test radiated emissions greater than 30 MHz When selecting a ferrite bead choose one with high impedance at high frequencies but low impedance at low frequencies Use a LC output filter if there are low frequency 1 MHz EMI sensitive circuits and or there are long wires from the amplifier to the speaker When both an LC filter and a ferrite bead filter are used the LC filter should be placed as close as possible to the IC followed by the ferrite bead filter 33 uH OUTP Y YS e e C2 Ly C4 HE 0 1 uF 1 0 47 33 uH OUTN MMe 0 C3
6. Computers and Peripherals Consumer Electronics Energy and Lighting Industrial Medical Security Space Avionics and Defense Video and Imaging TI E2E Community www ti com wirelessconnectivity www ti com computers www ti com consumer apps www ti com energy www ti com industrial www ti com medical www ti com security www ti com space avionics defense www ti com video Mailing Address Texas Instruments Post Office Box 655303 Dallas Texas 75265 Copyright 2013 Texas Instruments Incorporated
7. TEXAS INSTRUMENTS www ti com TPA3008D2 SLOS435C MAY 2004 REVISED AUGUST 2010 10 W STEREO CLASS D AUDIO POWER AMPLIFIER Check for Samples TPA3008D2 FEATURES 10 W Channel Into an 16 Q Load From a 17 V Supply Up to 92 Efficient Class D Operation Eliminates Need For Heatsinks 8 5 V to 18 V Single Supply Operation DESCRIPTION The TPA3008D2 is a 10 W per channel efficient class D audio amplifier for driving bridged tied stereo speakers The TPA3008D2 can drive stereo speakers as low as 8 The high efficiency of the TPA3008D2 eliminates the need for external heatsinks when Four Selectable Fixed Gain Settings Differential Inputs Minimizes Common Mode Noise Space Saving Thermally Enhanced PowerPAD Packaging Thermal and Short Circuit Protection With Auto Recovery Option Pinout Similar to TPA3000D Family APPLICATIONS LCD Monitors and TVs All In One PCs playing music The gain of the amplifier is controlled by two gain select pins The gain selections are 15 3 21 2 27 2 and 31 8 dB The outputs are fully protected against shorts to GND VCC and output to output shorts A fault terminal allows short circuit fault reporting and automatic recovery Thermal protection ensures that the maximum junction temperature is not exceeded 10 pF tour 220 nF 220
8. 2004 2010 Texas Instruments Incorporated Submit Documentation Feedback 23 Product Folder Link s TPA3008D2 TPA3008D2 SLOS435C MAY 2004 REVISED AUGUST 2010 www ti com REVISION HISTORY Changes from Revision B November 2004 to Revision C Page e Replaced the DISSIPATION RATING TABLE with the Thermal Information Table 2 24 Submit Documentation Feedback Copyright 2004 2010 Texas Instruments Incorporated Product Folder Link s TPA3008D2 PACKAGE OPTION ADDENDUM TEXAS INSTRUMENTS www ti com 11 Apr 2013 PACKAGING INFORMATION Orderable Device Status Package Type Package Pins Package Eco Plan Lead Ball Finish MSL Peak Temp Op Temp C Top Side Markings Samples 1 Drawing Qty 2 3 4 TPA3008D2PHP ACTIVE HTQFP PHP 48 250 pe CU NIPDAU Level 4 260C 72 HR 40 to 85 TPA3008D2 TPA3008D2PHPG4 ACTIVE HTQFP PHP 48 250 pea CU NIPDAU Level 4 260C 72 HR 40 to 85 TPA3008D2 TPA3008D2PHPR ACTIVE HTQFP PHP 48 1000 a CU NIPDAU Level 4 260C 72 HR 40 to 85 TPA3008D2 TPA3008D2PHPRG4 ACTIVE HTQFP PHP 48 1000 oc CU NIPDAU Level 4 260C 72 HR 40 to 85 TPA3008D2 The marketing status values are defined as follows ACTIVE Product device recommended for new designs LIFEBUY TI has announced that the device will be discontinued and a lifetime buy period is in effect NRND Not recommended for new designs Device is in production to support existing customers but TI does not recommend usin
9. This section focuses on the class D operation of the TPA3008D2 Traditional Class D Modulation Scheme The traditional class D modulation scheme which is used in the TPAO32D0x family has a differential output where each output is 180 degrees out of phase and changes from ground to the supply voltage Vcc Therefore the differential prefiltered output varies between positive and negative Vcc where filtered 5096 duty cycle yields 0 V across the load The traditional class D modulation scheme with voltage and current waveforms is shown in Figure 17 Note that even at an average of 0 V across the load 5096 duty cycle the current to the load is high causing high loss and thus causing a high supply current OUTP OUTN 12V Differential Voltage Across Load 12V Current Figure 17 Traditional Class D Modulation Scheme s Output Voltage and Current Waveforms Into Inductive Load With No Input TPA3008D2 Modulation Scheme The TPA3008D2 uses a modulation scheme that still has each output switching from 0 to the supply voltage However OUTP and OUTN are now in phase with each other with no input The duty cycle of OUTP is greater than 5096 and OUTN is less than 5096 for positive output voltages The duty cycle of OUTP is less than 5096 and OUTN is greater than 5096 for negative output voltages The voltage across the load sits at 0 V throughout most of the switch
10. Lo 0 1 uF Figure 19 Typical LC Output Filter Cutoff Frequency of 27 kHz Speaker Impedance 8 Q Copyright 2004 2010 Texas Instruments Incorporated Submit Documentation Feedback 15 Product Folder Link s TPA3008D2 TPA3008D2 up TEXAS INSTRUMENTS SLOS435C MAY 2004 REVISED AUGUST 2010 www ti com Ferrite Chip Bead OUTP Ferrite Chip Bead Figure 20 Typical Ferrite Chip Bead Filter Chip bead example Fair Rite 2512067007Y3 Gain setting via GAINO and GAIN1 inputs The gain of the TPA3008D2 is set by two input terminals GAINO and GAIN1 The gains listed in Table 2 are realized by changing the taps on the input resistors inside the amplifier This causes the input impedance Z to be dependent on the gain setting The actual gain settings are controlled by ratios of resistors so the gain variation from part to part is small However the input impedance may shift by 20 due to shifts in the actual resistance of the input resistors For design purposes the input network discussed in the next section should be designed assuming an input impedance of 26 kQ which is the absolute minimum input impedance of the TPA3008D2 At the lower gain settings the input impedance could increase as high as 165 kO Table 2 Gain Setting AMPLIFIER GAIN dB INPUT IMPEDANCE GAIN1 GAINO kQ TYP TYP 0 0 15 3 137 0 1 212 88 1 0 27 2 52 1 1 31 8 33 INPUT RESISTANC
11. PVCCL AVpn 29 5 Regulated output for use by internal cells and GAINO GAIN1 pins only Not specified for driving other external circuitry AVppREF 7 5 V Reference output connect to gain setting resistor or directly to GAINO GAIN1 BSLN 13 Bootstrap I O for left channel negative high side FET BSLP 24 Bootstrap for left channel positive high side FET BSRN 48 Bootstrap I O for right channel negative high side FET BSRP 37 Bootstrap I O for right channel positive high side FET COSC 28 y o I O for charge discharging currents onto capacitor for ramp generator Short circuit detect fault output FAULT E M Status is reset when power is cycled or SHUTDOWN is cycled GAINO 9 Gain select least significant bit TTL logic levels with compliance to AVpp GAIN1 10 Gain select most significant bit TTL logic levels with compliance to AVpp LINN 6 l Negative audio input for left channel LINP 5 l Positive audio input for left channel LOUTN 16 17 Class D 1 2 H bridge negative output for left channel LOUTP 20 21 Class D 1 2 H bridge positive output for left channel NC 8 pan 32 x No internal connection PGNDL 18 19 Power ground for left channel H bridge PGNDR 42 43 Power ground for right channel H bridge PVCCL 14 15 Power supply for left channel H bridge internally connected to pins 22 and 23 not connected to PVCCR or AVcc PVCCL 22 23 _ a bridge internally connected to pins 14 and 15 not PVCCR 38 39 _
12. REVISED AUGUST 2010 www ti com These devices have limited built in ESD protection The leads should be shorted together the device placed in conductive foam hind during storage or handling to prevent electrostatic damage to the MOS gates AVAILABLE OPTIONS T PACKAGED DEVICE 48 PIN HTQFP 2 40 C to 85 TPA3008D2PHP 1 The PHP package is available taped and reeled To order a taped and reeled part add the suffix R to the part number e g TPA3008D2PHPR 2 For the most current package and ordering information see the Package Option Addendum at the end of this document or see the TI website at www ti com ABSOLUTE MAXIMUM RATINGS over operating free air temperature range unless otherwise noted TPA3008D2 Supply voltage range AVcc PVcc 0 3 V to 20 V Load Impedance R 260 SHUTDOWN 0 3 V to VCC 0 3 V Input voltage range Vi GAINO GAIN1 RINN RINP LINN LINP 0 3Vto6V Continuous total power dissipation See Thermal Information Table Operating free air temperature range TA 40 C to 85 C Operating junction temperature range Ty 40 C to 150 C Storage temperature range 65 C to 150 C 1 Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated under
13. and back to the logic high state for normal operation This clears the short circuit flag and allows for normal operation if the short was removed If the short was not removed the protection circuitry again activates The fault terminal can be used for automatic recovery from a short circuit event or used to monitor the status with an external GPIO THERMAL PROTECTION Thermal protection on the TPA3008D2 prevents damage to the device when the internal die temperature exceeds 150 C There is a 15 degree tolerance on this trip point from device to device Once the die temperature exceeds the thermal set point the device enters into the shutdown state and the outputs are disabled This is not a latched fault The thermal fault is cleared once the temperature of the die is reduced by 20 The device begins normal operation at this point with no external system interaction PRINTED CIRCUIT BOARD PCB LAYOUT Because the TPA3008D2 is a class D amplifier that switches at a high frequency the layout of the printed circuit board PCB should be optimized according to the following guidelines for the best possible performance Decoupling capacitors The high frequency 0 1 uF decoupling capacitors should be placed as close to the PVCC pins 14 15 22 23 38 39 46 and 47 and AVcc pin 33 terminals as possible The V2P5 4 capacitor AVpp pin 29 capacitor and VCLAMP pins 25 and 36 capacitor should also be placed as close to the
14. device as possible Large 10 uF or greater bulk power supply decoupling capacitors should be placed near the TPA3008D2 on the PVCCL PVCCR and AV terminals e Grounding The AVG pin 33 decoupling capacitor AVpp pin 29 capacitor V2P5 pin 4 capacitor COSC pin 28 capacitor and ROSC pin 27 resistor should each be grounded to analog ground AGND pins 26 and 30 The PVCC decoupling capacitors should each be grounded to power ground PGND pins 18 19 42 and 43 Analog ground and power ground may be connected at the PowerPAD which should be used as a central ground connection or star ground for the TPA3008D2 Basically an island should be created with a single connection to PGND at the PowerPAD Output filter The ferrite EMI filter Figure 20 should be placed as close to the output terminals as possible for the best EMI performance The LC filter Figure 19 should be placed close to the outputs The capacitors used in both the ferrite and LC filters should be grounded to power ground If both filters are used the LC filter should be placed first following the outputs e PowerPAD The PowerPAD must be soldered to the PCB for proper thermal performance and optimal reliability The dimensions of the PowerPAD thermal land should be 5 mm by 5 mm 197 mils by 197 mils The PowerPAD size measures 4 55 x 4 55 mm Four rows of solid vias four vias per row 0 3302 mm or 13 mils diameter should be equally spaced underneath the thermal l
15. nF 0 1 uF 0 1 pF LI Li Li Li L1 Li Li Li Li Li Li E D EEG EO G 6 of E Oc 000222222000 e xx CI SHUTDOWN VCLAMPRET LIT Right Differential P IL RINN Inputs IR NC P Dp Cr RINP wee DAT UE CIC V2P5 0 47 uF Left Differential CIN LINP uc HO aE Inputs 0 47 uF CAE Linn uc Era ae ue 4 TPA3008D2 047 W CH AVODREF 809 AGND ET CONC AVDD 171 c an mri GAINo cosc po 1uF lt Control GAIN rosc Hr 220 PF 4 Ir FAULT AGND Hr 120 CII NC VCLAMPLEIT A AZZ RAR aa L E S 8 55 5 5 S 8 E Au yg o o 9 9 a 9 9 m HHHHHHHHHHHH doo L 10 uF 220 s c tour 2 nF Optional output filter for EMI suppression A Please be aware that an important notice concerning availability standard warranty and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet PowerPAD is a trademark of Texas Instruments PRODUCTION DATA information is current as of publication date Products conform to specifications per the terms of the Texas Instruments standard warranty Production processing does not necessarily include testing of all parameters Copyright 2004 2010 Texas Instruments Incorporated TPA3008D2 SLOS435C MAY 2004
16. recommended operating conditions is not implied Exposure to absolute maximum rated conditions for extended periods may affect device reliability THERMAL INFORMATION 1 2 TPA3008D2 THERMAL METRIC 2 UNITS PHP 48 PINS OJA Junction to ambient thermal resistance 27 7 OJCtop Junction to case top thermal resistance 14 8 Junction to board thermal resistance 9 4 C W VJT Junction to top characterization parameter 0 6 VJB Junction to board characterization parameter 5 6 OJcbot Junction to case bottom thermal resistance 0 3 1 For more information about traditional and new thermal metrics see the IC Package Thermal Metrics application report SPRA953 2 For thermal estimates of this device based on PCB copper area see the PCB Thermal Calculator RECOMMENDED OPERATING CONDITIONS T4 25 C unless otherwise noted MIN MAX UNIT Supply voltage Voc PVcc AVcc 8 5 18 V High level input voltage Vj SHUTDOWN GAINO GAIN1 2 V Low level input voltage Vi SHUTDOWN GAINO GAIN1 0 8 V SHUTDOWN V Voc 18V 10 HA High level input current li GAINO GAIN1 V 5 5 V Vcc 18 V 1 HA SHUTDOWN V 0 V Vcc 18V 1 Low level input current li GAINO GAIN1 V 5 5 V Vcc 18V 1 HA High level output voltage FAULT loy 100 pA AVpp 0 8 V V Low level output voltage Vo FAULT lo 100 HA AGND 0 8 V
17. 0k Figure 13 Submit Documentation Feedback Vcc Supply Current A ksyn Supply Ripple Rejection Ratio dB TEXAS INSTRUMENTS www ti com SUPPLY CURRENT vs TOTAL OUTPUT POWER 2 0 LC Filter 1 8 Resistive Load Stereo Operation 1 6 12 V 1 4 RL 8Q 1 2 Vec 12 V 1 16 Q 0 8 kas 0 6 Vcc 18 V RL 16Q 0 4 0 2 0 0 2 4 6 8 10 12 14 16 18 20 Po Total Output Power W Figure 12 SUPPLY RIPPLE REJECTION RATIO vs FREQUENCY 0 10 12 V V RiPPLE 200 20 8 9 Gain 15 6 dB 30 40 50 60 70 80 90 100 2 100 1k 10k 20k f Frequency Hz Figure 14 Copyright 2004 2010 Texas Instruments Incorporated Product Folder Link s TPA3008D2 T TPA3008D2 www ti com SLOS435C MAY 2004 REVISED AUGUST 2010 COMMON MODE REJECTION RATIO vs FREQUENCY Vcc 12 V Gain 15 6 dB RL 8Q Output Referred CMRR Common Mode Rejection Ratio dB 20 100 1k 10k 20k f Frequency Hz Figure 15 Copyright 2004 2010 Texas Instruments Incorporated Submit Documentation Feedback 11 Product Folder Link s TPA3008D2 TPA3008D2 ip TEXAS INSTRUMENTS SLO
18. E Each gain setting is achieved by varying the input resistance of the amplifier that can range from its smallest value 33 to the largest value 137 As a result if a single capacitor is used in the input high pass filter the 3 dB or cutoff frequency changes when changing gain steps Z Input IN Signal H The 3 dB frequency be calculated using Equation 5 Use Table 2 for Z values baa l 2 ZC 16 Submit Documentation Feedback Copyright 2004 2010 Texas Instruments Incorporated Product Folder Link s TPA3008D2 T ONNE TPA3008D2 www ti com SLOS435C MAY 2004 REVISED AUGUST 2010 INPUT CAPACITOR C In the typical application an input capacitor C is required to allow the amplifier to bias the input signal to the proper dc level for optimum operation In this case C and the input impedance of the amplifier Z form a high pass filter with the corner frequency determined in Equation 6 3dB fe 6 The value of C is important as it directly affects the bass low frequency performance of the circuit Consider the example where 4 is 137 and the specification calls for a flat bass response down to 20 Hz Equation 6 is reconfigured as Equation 7 7 In this example C is 58 nF so one would likely choose a value of 0 1 uF as this value is commonly used If the gain is known and is constant use Z from Table 2 to calculate C A furthe
19. FORMATION REEL DIMENSIONS TAPE DIMENSIONS Reel Diameter Dimension designed to accommodate the component width BO Dimension designed to accommodate the component length Dimension designed to accommodate the component thickness Y Overall width of the carrier tape Pitch between successive cavity centers Reel Width W1 QUADRANT ASSIGNMENTS FOR PIN 1 ORIENTATION IN TAPE O O OO O O O O O Sprocket Holes Q1 Q2 Q1 Q2 Q3 Q4 Q3 Q4 User Direction of Feed Pocket Quadrants All dimensions are nominal Device Package Package Pins SPQ Reel Reel BO KO P1 W Pin1 TPA3008D2PHPR HTQFP PHP 48 1000 330 0 16 4 9 6 9 6 1 5 12 0 16 0 Q2 Pack Materials Page 1 1p TEXAS PACKAGE MATERIALS INFORMATION INSTRUMENTS www ti com 26 Jan 2013 TAPE AND REEL BOX DIMENSIONS All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length mm Width mm Height mm TPA3008D2PHPR HTQFP PHP 48 1000 367 0 367 0 38 0 Pack Materials Page 2 MECHANICAL DATA PHP S PQFP 648 PowerPAD PLASTIC QUAD FLATPACK Thermal Pad See Note D
20. GUST 2010 Power Supply Signal R Analyzer Generator L 20 Hz 20 kHz a Basic Class AB Power Supply Low Pass RC Filter Signal Class D APA CSS Generator 20 Hz Low Pass RC Filter L ee b Filter Free and Traditional Class D A For efficiency measurements with filter free class D Rj should be an inductive load like a speaker Figure 21 Audio Measurement Systems The TPA3008D2 uses a modulation scheme that does not require an output filter for operation but they do sometimes require an RC low pass filter when making measurements This is because some analyzer inputs cannot accurately process the rapidly changing square wave output and therefore record an extremely high level of distortion The RC low pass measurement filter is used to remove the modulated waveforms so the analyzer can measure the output sine wave DIFFERENTIAL INPUT AND BTL OUTPUT All of the class D APAs and many class AB APAs have differential inputs and bridge tied load BTL outputs Differential inputs have two input pins per channel and amplify the difference in voltage between the pins Differential inputs reduce the common mode noise and distortion of the input circuit BTL is a term commonly used in audio to describe differential outputs BTL outputs have two output pins providing voltages that are 180 degrees out of phase The load is connected between these pins This has the added benefits of quadrupling the
21. IN1 22V GAINO 2 V 31 1 31 8 32 5 ton Turnon time Ciyaps 1 UF SHUTDOWN 2 V 16 ms tort Turnoff time C v2p5 1 uF SHUTDOWN 0 8 V 60 us AC ELECTRICAL CHARACTERISTICS Ta 25 Voc 12 V R 8 unless otherwise noted PARAMETER TEST CONDITIONS MIN TYP MAX UNIT DUE 200 mVpp ripple from 20 Hz to 1 kHz E Ksvr Supply voltage rejection ratio Gain 15 6 dB Inputs ac coupled to GND 70 dB THD N 0 13 f 1 kHz R 8 Q 5 THD N 10 f 1 kHz R 8 Q 8 5 Po Continuous output power THD N 0 16 f 1 kHz Ri 16 5 w Vcc 17 V THD N 1095 f 1 kHz Ri 16 10 Vcc 17 V THD N s harmonic distortion plus Po 1W f 1kHz R 8 Q 0 1 20 Hz to 22 kHz A weighted filter Va Output integrated noise floor Gain 15 6 dB 80 dB Crosstalk Po 1 W RI 8 Gain 15 6 dB 93 dB f 1 kHz Maximum output at THD N lt 0 5 SNR Signal to noise ratio f 2 1 kHz Gain 15 6 dB 97 dB Thermal trip point 150 Thermal hystersis 20 C Copyright 2004 2010 Texas Instruments Incorporated Product Folder Link s TPA3008D2 Submit Documentation Feedback TPA3008D2 SLOS435C MAY 2004 REVISED AUGUST 2010 V2P5 dco re cm Adj RINP dj V2P5 To Gain Adi GAINO Ei Gain Blocks and GAIN1 Control Start up Logic ROSC COSC AVppREF AVDD TTL Input SHUTDOWN Buffer VCC Compl LINN LINP 4 Submit Documentation Feedback FUNCTIONAL BLOCK DIAGRAM
22. ON NOISE vs vs FREQUENCY FREQUENCY o 10 10 2 Vee 12 V a Vcc 18 V RL 8Q M RL 289 5 Gain 21 6 dB 5 Gain 21 6 dB o z z 5 5 1 Po 0 5 W e 1 Po 2 5 W a a o E o Po 1W 0 1 T 01 r S T Po 1W o Po 2 5 W o z E I 0 01 Po 5W 0 01 0 005 20 100 1k 10k 20k 20 100 1k 10k 20k f Frequency Hz f Frequency Hz Figure 3 Figure 4 TOTAL HARMONIC DISTORTION NOISE TOTAL HARMONIC DISTORTION NOISE vs vs OUTPUT POWER OUTPUT POWER 20 10 10 Vcc 12 V 18 V 8 9 Ri 16 9 Gain 21 6 dB Gain 21 6 dB o Aa 0 1 THD N Total Harmonic Distortion Noise 96 THD N Total Harmonic Distortion Noise 96 0 01 0 01 20m 100 0 m 1 2 10 20 20m 100 m 200m 1 2 10 20 Po Output Power W Po Output Power W Figure 5 Figure 6 8 Submit Documentation Feedback Copyright 2004 2010 Texas Instruments Incorporated Product Folder Link s TPA3008D2 TEXAS INSTRUMENTS www ti com CLOSED LOOP RESPONSE 40 36 1 150 2 3 100 28 Gain 50 4 5 Phase I 20 0 S 46 50 12 12 V 8 R 8 9 100 Gain 32 dB 4 kHz RC LPF 150 0 10 100 1k 10k 80k f Frequency Hz Figure 7 OUTPUT POWER vs SUPPLY VOLTAGE z I 5 z a 5 o 5 o I
23. PL pin 25 and VCLAMPR pin 36 to ground and must be rated for at least 25 V The voltages at the VCLAMP terminals vary with Vcc and may not be used for powering any other circuitry Internal Regulated 5 V Supply AVpp The AVpp terminal pin 29 is the output of an internally generated 5 V supply used for the oscillator preamplifier and volume control circuitry It requires a 1 uF capacitor placed close to the pin to keep the regulator stable This regulated voltage can be used to control GAINO and GAIN1 terminals but should not be used to drive external circuitry Differential Input The differential input stage of the amplifier cancels any noise that appears on both input lines of the channel To use the TPA3008D2 with a differential source connect the positive lead of the audio source to the INP input and the negative lead from the audio source to the INN input To use the TPA3008D2 with a single ended source ac ground the INP or INN input through a capacitor equal in value to the input capacitor on INN or INP and apply the audio source to either input In a single ended input application the unused input should be ac grounded at the audio source instead of at the device input for best noise performance SHUTDOWN OPERATION The TPA3008D2 employs a shutdown mode of operation designed to reduce supply current lcc to the absolute minimum level during periods of nonuse for power conservation The SHUTDOWN input terminal should be hel
24. S435C MAY 2004 REVISED AUGUST 2010 www ti com APPLICATION INFORMATION PVCC 1nFZx asi nF PVCC e ll N3 220 nF l 220 nF 5g 10uF 10 nF g jH ca og S o Shutdown Mute a m Control gt VCLAMPR Right Differential NC inputs pp j 0 47 uF NC 0 47 uF Ale 2 47 uF Left Differential 9 NC Inputs 0 47 i pa 0 47 uF TPA3008D2 47 AGND AVDD Control 8 ROSC Fault Reporting 8 AGND VCLAMPL o a 0 1 uF 0 1 uF e e 10 uF 10uF 220 nF 1 M 4 220 nF tT IN Lel PVCC 1nF Q4nr Chip ferrite bead example Fair Rite 251206700743 shown for EMI suppression Figure 16 Stereo Class D With Differential Inputs 12 Submit Documentation Feedback Copyright 2004 2010 Texas Instruments Incorporated Product Folder Link s TPA3008D2 T ONNE TPA3008D2 www ti com SLOS435C MAY 2004 REVISED AUGUST 2010 CLASS D OPERATION
25. SED AUGUST 2010 Damage may occur if the voice coil cannot handle the additional heat generated from the high frequency switching current The amount of power dissipated in the speaker may be estimated by first considering the overall efficiency of the system If the on resistance rds on of the output transistors is considered to cause the dominant loss in the system then the maximum theoretical efficiency for the TPA3008D2 with an 8 O load is as follows R j j j 9 L 9 8 VA Efficiency theoretical 100 671 3 X 100 86 RL T mo 1 The maximum measured output power is approximately 8 5 W with an 12 V power supply The total theoretical power supplied P total for this worst case condition would therefore be as follows P 85W total Efficiency 0 86 2 The efficiency measured in the lab using 8 speaker was 81 The power not accounted for as dissipated across the rps on may be calculated by simply subtracting the theoretical power from the measured power theoretical 10 49 9 88 0 61W Other losses Pi total 3 total Measured The quiescent supply current at 12 V is measured to be 22 mA It can be assumed that the quiescent current encapsulates all remaining losses in the device i e biasing and switching losses It may be assumed that any remaining power is dissipated in the speaker and is calculated as follows 0 61W 12V x 22mA 0 35 W dis
26. V Copyright 2004 2010 Texas Instruments Incorporated Product Folder Link s TPA3008D2 2 Submit Documentation Feedback TEXAS INSTRUMENTS TPA3008D2 www ti com RECOMMENDED OPERATING CONDITIONS continued T4 25 unless otherwise noted SLOS435C MAY 2004 REVISED AUGUST 2010 MIN MAX UNIT Frequency is set by selection of ROSC and COSC Oscillator frequency fosc see the Application Information Section 200 300 mE Operating free air temperature Ta 40 85 C DC ELECTRICAL CHARACTERISTICS Ta 25 Voc 12 V R 8 unless otherwise noted PARAMETER TEST CONDITIONS MIN TYP UNIT Class D output offset voltage INN and INP connected together IVool measured differentially Gain 31 8 dB 5 2271 7 V2P5 2 5 V Bias voltage No load 2 5 V 10 mA SHUTDOWN 2 V AVpp 5 V internal supply voltage Vcc 8 5 V to 18 V 4 5 5 5 5 V PSRR Power supply rejection ratio Voc 11 5 V to 12 5 V 76 dB loc Quiescent supply current SHUTDOWN 2 V no load 11 22 mA Quiescent supply current in SUITFRASEN lcc sb shutdown mode SHUTDOWN 0 V 1 6 25 Vcc 12 V High side 600 DS on Drain source on state resistance 10 1 A Low side 500 mQ BEDV Total 1100 1300 GAINO 0 8 V 14 6 15 3 16 2 GAIN1 0 8 V GAINO 2 V 20 5 21 2 21 8 G Gain dB GAINO 0 8 V 26 4 27 2 27 8 GA
27. and The vias should connect to a solid copper plane either on an internal layer or on the bottom layer of the PCB The vias must be solid vias not thermal relief or webbed vias For additional information see the PowerPAD Thermally Enhanced Package application note SLMA002 For an example layout see the TPA3008D2 Evaluation Module TPA3008D2EVM User Manual SLOU165 Both the EVM user manual and the PowerPAD application note are available on the TI Web site at http www ti com Copyright 2004 2010 Texas Instruments Incorporated Submit Documentation Feedback 19 Product Folder Link s TPA3008D2 TPA3008D2 SLOS435C MAY 2004 REVISED AUGUST 2010 www ti com BASIC MEASUREMENT SYSTEM This application note focuses on methods that use the basic equipment listed below Audio analyzer or spectrum analyzer Digital multimeter DMM Oscilloscope Twisted pair wires Signal generator Power resistor s Linear regulated power supply Filter components EVM or other complete audio circuit Figure 21 shows the block diagrams of basic measurement systems for class AB and class D amplifiers A sine wave is normally used as the input signal because it consists of the fundamental frequency only no other harmonics are present An analyzer is then connected to the APA output to measure the voltage output The analyzer must be capable of measuring the entire audio bandwidth A regulated dc power supply is used to r
28. anty in TI s terms and conditions of sale of semiconductor products Testing and other quality control techniques are used to the extent TI deems necessary to support this warranty Except where mandated by applicable law testing of all parameters of each component is not necessarily performed TI assumes no liability for applications assistance or the design of Buyers products Buyers are responsible for their products and applications using Tl components To minimize the risks associated with Buyers products and applications Buyers should provide adequate design and operating safeguards TI does not warrant or represent that any license either express or implied is granted under any patent right copyright mask work right or other intellectual property right relating to any combination machine or process in which TI components or services are used Information published by TI regarding third party products or services does not constitute a license to use such products or services or a warranty or endorsement thereof Use of such information may require a license from a third party under the patents or other intellectual property of the third party or a license from TI under the patents or other intellectual property of TI Reproduction of significant portions of TI information in TI data books or data sheets is permissible only if reproduction is without alteration and is accompanied by all associated warranties conditions limitations and no
29. ation of the analyzer input voltage through the voltage divider formed by and Rana A rule of thumb is that should be small 7 100 for most measurements This reduces the measurement error to less than 196 for Rana 2 10 RANA RANA EE O 8 fo 9 An exception occurs with the efficiency measurements where must be increased by a factor of ten to reduce the current shunted through the filter Cry must be decreased by a factor of ten to maintain the same cutoff frequency See Table 4 for the recommended filter component values Once fc is determined and is selected the filter capacitance is calculated using Equation 9 When the calculated value is not available it is better to choose a smaller capacitance value to keep fc above the minimum desired value calculated in Equation 10 1 c R Table 4 shows recommended values of Rpj r and Cri based on common component values The value of fc was originally calculated to be 28 kHz for an fmax of 20 kHz however was calculated to be 57 000 pF but the nearest values of 56 000 pF and 51 000 pF were not available A 47 000 pF capacitor was used instead and fc is 34 kHz which is above the desired value of 28 kHz C FILT 2x xf FILT 10 Table 4 Typical RC Measurement Filter Values MEASUREMENT RAILT Efficiency 1000 Q 5 600 pF All other measurements 100 Q 56 000 pF Copyright
30. ations and peak solder temperature e Multiple Top Side Markings will be inside parentheses Only one Top Side Marking contained in parentheses and separated by a will appear on a device If a line is indented then it is a continuation of the previous line and the two combined represent the entire Top Side Marking for that device Important Information and Disclaimer The information provided on this page represents Tl s knowledge and belief as of the date that it is provided TI bases its knowledge and belief on information provided by third parties and makes no representation or warranty as to the accuracy of such information Efforts are underway to better integrate information from third parties TI has taken and continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals TI and TI suppliers consider certain information to be proprietary and thus CAS numbers and other limited information may not be available for release In no event shall TI s liability arising out of such information exceed the total purchase price of the TI part s at issue in this document sold by TI to Customer on an annual basis Addendum Page 1 H PACKAGE OPTION ADDENDUM TEXAS INSTRUMENTS www ti com 11 Apr 2013 Addendum Page 2 1p TEXAS PACKAGE MATERIALS INFORMATION INSTRUMENTS www ti com 26 Jan 2013 TAPE AND REEL IN
31. causes power dissipation The speaker is both resistive and reactive whereas an LC filter is almost purely reactive The TPA3008D2 modulation scheme has little loss in the load without a filter because the pulses are short and the change in voltage is Vcc instead of 2 x Vcc As the output power increases the pulses widen making the ripple current larger Ripple current could be filtered with an LC filter for increased efficiency but for most applications the filter is not needed An LC filter with a cutoff frequency less than the class D switching frequency allows the switching current to flow through the filter instead of the load The filter has less resistance than the speaker which results in less power dissipation therefore increasing efficiency Effects of Applying a Square Wave Into a Speaker Audio specialists have advised for years not to apply a square wave to speakers If the amplitude of the waveform is high enough and the frequency of the square wave is within the bandwidth of the speaker the square wave could cause the voice coil to jump out of the air gap and or scar the voice coil A 250 kHz switching frequency however does not significantly move the voice coil as the cone movement is proportional to 1 f for frequencies beyond the audio band 14 Submit Documentation Feedback Copyright 2004 2010 Texas Instruments Incorporated Product Folder Link s TPA3008D2 T ONNE TPA3008D2 www ti com SLOS435C MAY 2004 REVI
32. circuit as shown in Figure 23 R is the load impedance that the APA is driving for the test The analyzer input impedance specifications should be available and substituted for Rana and Cana The filter components Rp and Cg can then be derived for the system The filter should be grounded to the APA near the output ground pins or at the power supply ground pin to minimize ground loops 22 Submit Documentation Feedback Copyright 2004 2010 Texas Instruments Incorporated Product Folder Link s TPA3008D2 T ONNE TPA3008D2 www ti com SLOS435C MAY 2004 REVISED AUGUST 2010 RClowPassFilters AP Analyzer Input O n Cuir AN Cana Ban Miz V RS OY Vour T Peur SR il Cana Ban To APA 4 GND LA j AA 0 5 J Figure 23 Measurement Low Pass Filter Derivation Circuit Class D APAs The transfer function for this circuit is shown in Equation 8 where RegCea Reg Rent Rana and Ceo Cana The filter frequency should be set above fmax the highest frequency of the measurement bandwidth to avoid attenuating the audio signal Equation 9 provides this cutoff frequency fc The value of Rgt must be chosen large enough to minimize current that is shunted from the load yet small enough to minimize the attenu
33. ctions Use shielding when the system environment is noisy Ensure that the cables from the power supply to the APA and from the APA to the load can handle the large currents see Table 3 Table 3 shows the recommended wire size for the power supply and load cables of the APA system The real concern is the dc or ac power loss that occurs as the current flows through the cable These recommendations are based on 12 inch long wire with a 20 kHz sine wave signal at 25 C Table 3 Recommended Minimum Wire Size for Power Cables DC POWER LOSS AC POWER LOSS Pour W AWG Size MW MW 10 4 18 22 16 40 18 42 2 4 18 22 3 2 8 3 7 8 5 1 8 22 28 2 8 2 1 8 1 20 75 8 22 28 1 5 6 1 1 6 6 2 CLASS D RC LOW PASS FILTER An RC filter is used to reduce the square wave output when the analyzer inputs cannot process the pulse width modulated class D output waveform This filter has little effect on the measurement accuracy because the cutoff frequency is set above the audio band The high frequency of the square wave has negligible impact on measurement accuracy because it is well above the audible frequency range and the speaker cone cannot respond at such a fast rate The RC filter is not required when an LC low pass filter is used such as with the class D APAs that employ the traditional modulation scheme TPA032D0x TPA005Dxx The component values of the RC filter are selected using the equivalent output
34. d high see specification table for trip point during normal operation when the amplifier is in use Pulling SHUTDOWN low causes the outputs to mute and the amplifier to enter a low current state Never leave SHUTDOWN unconnected because amplifier operation would be unpredictable For the best power off pop performance place the amplifier in the shutdown mode prior to removing the power supply voltage USING LOW ESR CAPACITORS Low ESR capacitors are recommended throughout this application section A real as opposed to ideal capacitor can be modeled simply as a resistor in series with an ideal capacitor The voltage drop across this resistor minimizes the beneficial effects of the capacitor in the circuit The lower the equivalent value of this resistance the more the real capacitor behaves like an ideal capacitor 18 Submit Documentation Feedback Copyright 2004 2010 Texas Instruments Incorporated Product Folder Link s TPA3008D2 T ONNE TPA3008D2 www ti com SLOS435C MAY 2004 REVISED AUGUST 2010 SHORT CIRCUIT PROTECTION AND AUTOMATIC RECOVERY FEATURE The TPA3008D2 has short circuit protection circuitry on the outputs that prevents damage to the device during output to output shorts output to GND shorts and output to Vcc shorts When a short circuit is detected on the outputs the part immediately disables the output drive This is a latched fault and must be reset by cycling the voltage on the SHUTDOWN pin to a logic low
35. d requirements Nonetheless such components are subject to these terms No TI components are authorized for use in FDA Class Ill or similar life critical medical equipment unless authorized officers of the parties have executed a special agreement specifically governing such use Only those TI components which TI has specifically designated as military grade or enhanced plastic are designed and intended for use in military aerospace applications or environments Buyer acknowledges and agrees that any military or aerospace use of TI components which have not been so designated is solely at the Buyer s risk and that Buyer is solely responsible for compliance with all legal and regulatory requirements in connection with such use TI has specifically designated certain components as meeting ISO TS16949 requirements mainly for automotive use In any case of use of non designated products TI will not be responsible for any failure to meet ISO TS16949 Products Applications Audio www ti com audio Automotive and Transportation www ti com automotive Amplifiers amplifier ti com Communications and Telecom www ti com communications Data Converters DLP Products DSP Clocks and Timers Interface Logic Power Mgmt Microcontrollers RFID OMAP Applications Processors Wireless Connectivity dataconverter ti com www dlp com www ti com clocks interface ti com logic ti com microcontroller ti com www ti rfid com www ti com omap
36. educe the noise and distortion injected into the APA through the power pins A System Two audio measurement system AP II Reference 1 by Audio Precision includes the signal generator and analyzer in one package The generator output and amplifier input must be ac coupled However the EVMs already have the ac coupling capacitors Cn so no additional coupling is required The generator output impedance should be low to avoid attenuating the test signal and is important because the input resistance of APAs is not high Conversely the analyzer input impedance should be high The output impedance of the APA is normally in the hundreds of milliohms and can be ignored for all but the power related calculations Figure 21 a shows a class AB amplifier system It takes an analog signal input and produces an analog signal output This amplifier circuit can be directly connected to the AP II or other analyzer input This is not true of the class D amplifier system shown in Figure 21 b which requires low pass filters in most cases in order to measure the audio output waveforms This is because it takes an analog input signal and converts it into a pulse width modulated PWM output signal that is not accurately processed by some analyzers 20 Submit Documentation Feedback Copyright 2004 2010 Texas Instruments Incorporated Product Folder Link s TPA3008D2 TEXAS INSTRUMENTS TPA3008D2 www ti com SLOS435C MAY 2004 REVISED AU
37. ermally Enhanced Package Texas Instruments Literature No SLMA002 SLMA004 and also the Product Data Sheets for specific thermal information via requirements and recommended board layout These documents are available at www ti com http www ti com gt E Laser cutting apertures with trapezoidal walls and also rounding corners will offer better paste release Customers should contact their board assembly site for stencil design recommendations Refer to IPC 7525 for stencil design considerations F Customers should contact their board fabrication site for recommended solder mask tolerances and via tenting options for vias placed in the thermal pad PowerPAD is a trademark of Texas Instruments X TEXAS INSTRUMENTS www ti com IMPORTANT NOTICE Texas Instruments Incorporated and its subsidiaries Tl reserve the right to make corrections enhancements improvements and other changes to its semiconductor products and services per JESD46 latest issue and to discontinue any product or service per JESD48 latest issue Buyers should obtain the latest relevant information before placing orders and should verify that such information is current and complete All semiconductor products also referred to herein as components are sold subject to TI s terms and conditions of sale supplied at the time of order acknowledgment TI warrants performance of its components to the specifications applicable at the time of sale in accordance with the warr
38. g this part in a new design PREVIEW Device has been announced but is not in production Samples may or may not be available OBSOLETE TI has discontinued the production of the device Eco Plan The planned eco friendly classification Pb Free ROHS Pb Free ROHS Exempt or Green RoHS 8 no Sb Br please check http www ti com productcontent for the latest availability information and additional product content details TBD The Pb Free Green conversion plan has not been defined Pb Free RoHS TI s terms Lead Free or Pb Free mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances including the requirement that lead not exceed 0 1 by weight in homogeneous materials Where designed to be soldered at high temperatures TI Pb Free products are suitable for use in specified lead free processes Pb Free RoHS Exempt This component has a RoHS exemption for either 1 lead based flip chip solder bumps used between the die and package or 2 lead based die adhesive used between the die and leadframe The component is otherwise considered Pb Free ROHS compatible as defined above Green RoHS amp no Sb Br TI defines Green to mean Pb Free RoHS compatible and free of Bromine Br and Antimony Sb based flame retardants Br or Sb do not exceed 0 1 by weight in homogeneous material 9 MSL Peak Temp The Moisture Sensitivity Level rating according to the JEDEC industry standard classific
39. ing period greatly reducing the switching current which reduces any I R losses in the load Copyright 2004 2010 Texas Instruments Incorporated Submit Documentation Feedback 13 Product Folder Link s TPA3008D2 TPA3008D2 SLOS435C MAY 2004 REVISED AUGUST 2010 www ti com OUTP OUTN Differential 412V Vol oltage ov Across Load 12V Output 0 V Current Ru OUTN Output 0 V Differential 412V fl ji LE BL Voltage ov Across iay Load 7 E looo Aa Current Figure 18 The TPA3008D2 Output Voltage and Current Waveforms Into an Inductive Load Efficiency LC Filter Required With the Traditional Class D Modulation Scheme The main reason that the traditional class D amplifier needs an output filter is that the switching waveform results in maximum current flow This causes more loss in the load which causes lower efficiency The ripple current is large for the traditional modulation scheme because the ripple current is proportional to voltage multiplied by the time at that voltage The differential voltage swing is 2 x Vcc and the time at each voltage is half the period for the traditional modulation scheme An ideal LC filter is needed to store the ripple current from each half cycle for the next half cycle while any resistance
40. l Biases and References Start up and Protection Logic Detect VDDok AVC VCCok Product Folder Link s TPA3008D2 TEXAS INSTRUMENTS www ti com VCLAMPR BSRN PVCCR 2 ROUTN 2 PGNDR BSRP PVCCR 2 ROUTP 2 PGNDR FAULT AVCC AGND 2 VCLAMPL BSLN PVCCL 2 LOUTN 2 PGNDL BSLP PVCCL 2 LOUTP 2 PGNDL Copyright 2004 2010 Texas Instruments Incorporated TEXAS INSTRUMENTS TPA3008D2 www ti com SLOS435C MAY 2004 REVISED AUGUST 2010 PHP PACKAGE TOP VIEW SHUTDOWN VCLAMPR RINN NC RINP NC V2P5 AVcc LINP NC LINN NC RER TPA3008D2 pia NC AVpp GAINO COSC GAIN1 ROSC FAULT AGND NC VCLAMPL Copyright 2004 2010 Texas Instruments Incorporated Submit Documentation Feedback 5 Product Folder Link s TPA3008D2 TPA3008D2 SLOS435C MAY 2004 REVISED AUGUST 2010 TEXAS INSTRUMENTS www ti com TERMINAL FUNCTIONS PIN NAME PIN NUMBER yo DESCRIPTION AGND 26 30 Analog ground for digital analog cells in core AVcc 33 High voltage analog power supply not connected internally to PVCCR or
41. m electrolytic capacitor of 10 UF or greater placed near the audio power amplifier is recommended The 10 uF capacitor also serves as local storage capacitor for supplying current during large signal transients on the amplifier outputs BSN and BSP Capacitors The full H bridge output stages use only NMOS transistors Therefore they require bootstrap capacitors for the high side of each output to turn on correctly A 220 nF ceramic capacitor rated for at least 25 V must be connected from each output to its corresponding bootstrap input Specifically one 220 nF capacitor must be connected from xOUTP to xBSP and one 220 nF capacitor must be connected from xOUTN to xBSN See the application circuit diagram in Figure 16 The bootstrap capacitors connected between the BSxx pins and corresponding output function as a floating power supply for the high side N channel power MOSFET gate drive circuitry During each high side switching cycle the bootstrap capacitors hold the gate to source voltage high enough to keep the high side MOSFETs turned on Copyright 2004 2010 Texas Instruments Incorporated Submit Documentation Feedback 17 Product Folder Link s TPA3008D2 TPA3008D2 SLOS435C MAY 2004 REVISED AUGUST 2010 www ti com VCLAMP Capacitors To ensure that the maximum gate to source voltage for the NMOS output transistors is not exceeded two internal regulators clamp the gate voltage Two 1 uF capacitors must be connected from VCLAM
42. on the PowerPAD package and how to take advantage of its heat dissipating abilities refer to Technical Brief PowerPAD Thermally Enhanced Package Texas Instruments Literature No SLMAO02 and Application Brief PowerPAD Made Easy Texas Instruments Literature No SLMA004 Both documents are available at www ti com The exposed thermal pad dimensions for this package are shown in the following illustration 25 36 1 Exposed Thermal Pad Top View Exposed Thermal Pad Dimensions 4206329 4 N 04 12 NOTE A All linear dimensions are in millimeters A Tie strap features moy not be present PowerPAD is a trademark of Texas Instruments Xt TEXAS INSTRUMENTS www ti com LAND PATTERN DATA PHP S PQFP 648 PowerPAD PLASTIC QUAD FLATPACK Example Board Layout 0 127mm Thick Stencil Design Example Via pattern and copper pad size Reference table below for other may vary depending on layout constraints solder stencil thicknesses Note E 44 0 5 48x1 55 05 1111 CJ 48x0 25 co 1 Example Solder Mask Opening NG ote F Pad Geometry 0 05 j Note All Around 4207626 4 H 04 12 NOTES A All linear dimensions are in millimeters B This drawing is subject to change without notice D Publication IPC 7351 is recommended for alternate designs This package is designed to be soldered to a thermal pad on the board Refer to Technical Brief PowerPad Th
43. output power to the load and eliminating a dc blocking capacitor A block diagram of the measurement circuit is shown in Figure 22 The differential input is a balanced input meaning the positive 4 and negative pins have the same impedance to ground Similarly the BTL output equates to a balanced output Copyright 2004 2010 Texas Instruments Incorporated Submit Documentation Feedback 21 Product Folder Link s TPA3008D2 TPA3008D2 i TEXAS INSTRUMENTS SLOS435C MAY 2004 REVISED AUGUST 2010 www ti com Evaluation Module Generator Audio Power Amplifier Low Pass Bas Filter pol B Low Pass RC Filter gt I pane Twisted Pair Wire Twisted Pair Wire Figure 22 Differential Input BTL Output Measurement Circuit The generator should have balanced outputs and the signal should be balanced for best results An unbalanced output can be used but it may create a ground loop that affects the measurement accuracy The analyzer must also have balanced inputs for the system to be fully balanced thereby cancelling out any common mode noise in the circuit and providing the most accurate measurement The following general rules should be followed when connecting to APAs with differential inputs and BTL outputs Use a balanced source to supply the input signal Use an analyzer with balanced inputs Use twisted pair wire for all conne
44. r consideration for this capacitor is the leakage path from the input source through the input network C and the feedback network to the load This leakage current creates a dc offset voltage at the input to the amplifier that reduces useful headroom especially in high gain applications For this reason a low leakage tantalum or ceramic capacitor is the best choice When polarized capacitors are used the positive side of the capacitor should face the amplifier input in most applications as the dc level there is held at 2 5 V which is likely higher than the source dc level Note that it is important to confirm the capacitor polarity in the application For the best pop performance C should be less than or equal to Power Supply Decoupling Cs The TPA3008D2 is a high performance CMOS audio amplifier that requires adequate power supply decoupling to ensure that the output total harmonic distortion THD is as low as possible Power supply decoupling also prevents oscillations for long lead lengths between the amplifier and the speaker The optimum decoupling is achieved by using two capacitors of different types that target different types of noise on the power supply leads For higher frequency transients spikes or digital hash on the line a good low equivalent series resistance ESR ceramic capacitor typically 0 1 uF placed as close as possible to the device Vcc lead works best For filtering lower frequency noise signals a larger aluminu
45. tices TI is not responsible or liable for such altered documentation Information of third parties may be subject to additional restrictions Resale of TI components or services with statements different from or beyond the parameters stated by TI for that component or service voids all express and any implied warranties for the associated TI component or service and is an unfair and deceptive business practice Tl is not responsible or liable for any such statements Buyer acknowledges and agrees that it is solely responsible for compliance with all legal regulatory and safety related requirements concerning its products and any use of TI components in its applications notwithstanding any applications related information or support that may be provided by TI Buyer represents and agrees that it has all the necessary expertise to create and implement safeguards which anticipate dangerous consequences of failures monitor failures and their consequences lessen the likelihood of failures that might cause harm and take appropriate remedial actions Buyer will fully indemnify TI and its representatives against any damages arising out of the use of any TI components in safety critical applications In some cases TI components may be promoted specifically to facilitate safety related applications With such components TI s goal is to help enable customers to design and create their own end product solutions that meet applicable functional safety standards an
Download Pdf Manuals
Related Search