TDA7491LP STMicroelectronics, TDA7491LP Datasheet
TDA7491LP
Specifications of TDA7491LP
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TDA7491LP Summary of contents
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... LCD TVs and monitors. Thanks to the high efficiency and exposed-pad-down (EPD) package no separate heatsink is required. Furthermore, the filterless operation allows a reduction in the external component count. The TDA7491LP is pin to pin compatible with the TDA7491P and TDA7491HV. PowerSSO-36 EPD PowerSSO-36 EPD Doc ID 13541 Rev 4 TDA7491LP ...
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... Input resistance and capacitance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 7.4 Internal and external clocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 7.4.1 7.4.2 7.5 Filterless modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 7.6 Output low-pass filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 7.7 Protection function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 7.8 Diagnostic output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 7.9 Heatsink requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 2/ Master mode (internal clock Slave mode (external clock Doc ID 13541 Rev 4 TDA7491LP ...
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... TDA7491LP 8 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Doc ID 13541 Rev 4 Contents 3/34 ...
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... List of tables Table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Table 2. Pin description list . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Table 3. Absolute maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Table 4. Thermal data Table 5. Electrical specifications Table 6. PowerSSO-36 EPD dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Table 7. Mode settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Table 8. Gain settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Table 9. How to set up SYNCLK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Table 10. Document revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 4/34 Doc ID 13541 Rev 4 TDA7491LP ...
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... Current consumption vs voltage on pin MUTE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Figure 30. Attenuation vs voltage on pin MUTE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Figure 31. Current consumption vs voltage on pin STBY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Figure 32. Attenuation vs voltage on pin STBY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Figure 33. Test board (TDA7491LP) layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Figure 34. PowerSSO-36 EPD outline drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Figure 35. Applications circuit for class-D amplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Figure 36. Standby and mute circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Figure 37. ...
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... Device block diagram 1 Device block diagram Figure 1 shows the block diagram of one of the two identical channels of the TDA7491LP. Figure 1. Internal block diagram (one channel only) 6/34 Doc ID 13541 Rev 4 TDA7491LP ...
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... TDA7491LP 2 Pin description 2.1 Pin out Figure 2. Pin connection (top view, PCB view) SUB_GND OUTPB OUTPB PGNDB PGNDB PVCCB PVCCB OUTNB OUTNB OUTNA OUTNA PVCCA PVCCA PGNDA PGNDA OUTPA OUTPA exposed pad down Connect to ground PGND Doc ID 13541 Rev 4 Pin description ...
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... Positive differential input of right channel INPUT Negative differential input of right channel OUT Half VDDS (nominal) referred to ground POWER Signal power supply OUT 3.3-V (nominal) regulator output referred to power supply Exposed pad for ground-plane heatsink connected to - GND Doc ID 13541 Rev 4 TDA7491LP Description ...
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... TDA7491LP 3 Electrical specifications 3.1 Absolute maximum ratings Table 3. Absolute maximum ratings Symbol V DC supply voltage for pins PVCCA, PVCCB, SVCC CC T Operating temperature op T Junction temperature j T Storage temperature stg 3.2 Thermal data Table 4. Thermal data Symbol R Thermal resistance, junction to case ...
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... Hz 0 µF SVR - Internal oscillator With internal oscillator With external oscillator - MUTE V < 0 STBY V > 2.5 V, STBY V < 0.8 V MUTE V > 2.5 V, STBY V > 2.5 V MUTE + 182 kHz OSC SYNCLK SW Doc ID 13541 Rev 4 TDA7491LP Min Typ - - 0.1 0.2 ...
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... TDA7491LP 4 Characterization curves The following characterization curves were made using the TDA7491LP demo board. The LC filter for the 4-Ω load uses components of 15 µH and 470 nF, whilst that for the 8-Ω load uses 33 µH and 220 nF. All other test conditions are given along side the corresponding curves. ...
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... Rosc = 39 kΩ, Cosc = 100 nF kHz dB Tamb = 25 Specification limits: Typical: THD <0.5% Figure 7. Frequency response Test conditions 6 Ω Rosc = 39 kΩ, Cosc = 100 nF kHz dB Tamb = 25 Cin = 1 uF Specification limits: Max kHz 12/34 THD (%) Po per channel (W) THD(%) Po (dB) Doc ID 13541 Rev 4 TDA7491LP Frequency (Hz) Frequency (Hz) ...
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... TDA7491LP Figure 8. Crosstalk vs frequency Test conditions 6 Ω Rosc = 39 kΩ, Cosc = 100 nF kHz dB Tamb = 25 Specification limits: Typical: > kHz Figure 9. FFT (0 dB) Test conditions 6 Ω Rosc = 39 kΩ, Cosc = 100 nF kHz dB Tamb = 25 Specification limits: Typical: >60 dB for the harmonic frequency Figure 10. FFT (-60 dB) ...
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... Rosc = 39 kΩ, Cosc = 100 nF dB, Tamb = 25 Figure 13. Closed-loop gain vs frequency Test conditions 6 Ω Rosc = 39 kΩ, Cosc = 100 nF kHz kHz 20, 26, 30 and 32 dB Tamb = 25 14/34 PSRR (dB) Frequency (Hz) Efficiency (%) per channel (W) Gain (dB) Frequency (Hz) Doc ID 13541 Rev 4 TDA7491LP Pd (W) 2 1.8 1.6 1.4 1.2 1 0.8 0.6 0.4 0 ...
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... TDA7491LP Figure 14. Current consumption vs voltage on pin MUTE Test conditions 6 Ω Rosc = 39 kΩ, Cosc = 100 nF, Vin = dB, Tamb = 25 Figure 15. Attenuation vs voltage on pin MUTE Test conditions 6 Ω Rosc = 39 kΩ, Cosc = 100 nF kHz 0dB ( kHz dB, Tamb = 25 Figure 16. Current consumption vs voltage on pin STBY Test conditions ...
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... Figure 18. Output power vs supply voltage Test conditions Ω Rosc = 39 kΩ, Cosc =100 nF kHz dB, Tamb = 25 Specification limits: Typical THD = 10 THD = 1% 16/34 Attenuation (dB -10 -20 -30 -40 -50 -60 -70 -80 - Ω Doc ID 13541 Rev 4 TDA7491LP 1.5 2 2.5 3 3.5 Vstby(V) THD =10% THD = Supply voltage (V) ...
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... TDA7491LP Figure 19. THD vs output power (1 kHz) Test conditions Ω Rosc = 39 kΩ, Cosc = 100 nF kHz dB, Tamb = 25 Specification limits: Typical THD = 10% Figure 20. THD vs output power (100 Hz) Test conditions Ω Rosc = 39 kΩ, Cosc = 100 nF 100 Hz dB, Tamb = 25 Specification limits: Typical THD = 10% Figure 21 ...
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... Frequency (Hz) FFT (dB) +10 +0 -10 -20 -30 -40 -50 -60 -70 -80 -90 -100 -110 -120 -130 -140 -150 20 50 100 200 500 1k Frequency (Hz) Doc ID 13541 Rev 4 TDA7491LP 2k 5k 10k 30k 2k 5k 10k 20k 2k 5k 10k 20k ...
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... TDA7491LP Figure 25. FFT (-60 dB) Test conditions Ω Rosc = 39 kΩ, Cosc = 100 nF kHz dB - dB) Tamb = 25 Specification limits: Typical: >90 dB for the harmonic frequency Figure 26. Power supply rejection ratio vs frequency Test conditions Ω Rosc = 39 kΩ, Cosc = 100 nF, Vin = dB, Tamb = 25 Figure 27. Power dissipation and efficiency vs output power ...
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... Rosc = 39 kΩ, Cosc = 100 nF kHz 0dB ( kHz dB, Tamb = 25 20/34 Amplitude (dB +1 +0 -2.5 -3 -3 100 200 500 1k Hz Frequency (Hz (mA 0.5 1.0 1.5 2.0 Mute voltage (V) Attenuation (dB) Mute voltage (V) Doc ID 13541 Rev 4 TDA7491LP 2k 5k 10k 20k 30k 2.5 3.0 3.5 ...
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... TDA7491LP Figure 31. Current consumption vs voltage on pin STBY Test conditions Ω Rosc = 39 kΩ, Cosc = 100 nF, Vin = dB, Tamb = 25 Figure 32. Attenuation vs voltage on pin STBY Test conditions Ω Rosc = 39 kΩ, Cosc = 100 nF kHz kHz dB, Tamb = 25 Iq (mA) Standby voltage (V) Attenuation (dB) Standby voltage (V) Doc ID 13541 Rev 4 ...
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... Characterization curves 4.3 Test board Figure 33. Test board (TDA7491LP) layout 22/34 Doc ID 13541 Rev 4 TDA7491LP ...
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... TDA7491LP 5 Package mechanical data The TDA7491LP comes in a 36-pin PowerSSO package with exposed pad down (EPD). Figure 34 below shows the package outline and Figure 34. PowerSSO-36 EPD outline drawing Table 6 gives the dimensions. Doc ID 13541 Rev 4 Package mechanical data 23/34 ...
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... Doc ID 13541 Rev 4 TDA7491LP Dimensions in inches Min Typ 0.085 - 0.097 0.085 - 0.094 0.000 - 0.004 0.007 - 0.014 0.009 - 0.013 0.398 - 0.413 0.291 - 0.299 - 0.020 - - 0.335 - - 0.091 - - - 0.004 0.398 - 0 ...
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... TDA7491LP 6 Applications circuit Figure 35. Applications circuit for class-D amplifier Input settings for gain: GAIN0 : GAIN1 3 3.3 V TDA7491LP Input settings for standby, mute and play: Nominal gain STBY : MUTE 3.3 V Doc ID 13541 Rev 4 Applications circuit Mode Standby Standby Mute ...
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... Applications information 7.1 Mode selection The three operating modes of the TDA7491LP are set by the two inputs STBY (pin 20) and MUTE (pin 21). Standby mode: all circuits are turned off, very low current consumption. Mute mode: inputs are connected to ground and the positive and negative PWM outputs are at 50% duty cycle ...
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... TDA7491LP 7.2 Gain setting The gain of the TDA7491LP is set by the two inputs, GAIN0 (pin 30) and GAIN1 (pin 31). Internally, the gain is set by changing the feedback resistors of the amplifier. Table 8. Gain settings GAIN0 7.3 Input resistance and capacitance The input impedance is set by an internal resistor kΩ (typical). An input capacitor (Ci) is required to couple the AC input signal ...
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... If two or more class-D amplifiers are used in the same system recommended that all devices operate at the same clock frequency. This can be implemented by using one TDA7491LP as master clock, while the other devices are in slave mode (that is, externally clocked. The clock interconnect is via pin SYNCLK of each device. As explained below, SYNCLK is an output in master mode and an input in slave mode ...
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... TDA7491LP can be used without a filter before the speaker, because the frequency of the TDA7491LP output is beyond the audio frequency, the audio signal can be recovered by the inherent inductance of the speaker and natural filter of the human ear. Figure 40. Unipolar PWM output ...
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... It is necessary to choose the L-C component values depending on the loud-speaker impedance. Some typical values, which give a cut-off frequency of 27 kHz, are shown in Figure 41 Figure 41. Typical LC filter for a 8-Ω speaker Figure 42. Typical LC filter for a 4-Ω speaker 30/34 and Figure 42 below. Doc ID 13541 Rev 4 TDA7491LP ...
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... TDA7491LP 7.7 Protection function The TDA7491LP is fully protected against overvoltages, undervoltages, overcurrents and thermal overloads as explained here. Overvoltage protection (OVP) If the supply voltage exceeds the value for V page 9 the overvoltage protection is activated which forces the outputs to the high-impedance state. When the supply voltage drops to below the threshold value the device restarts ...
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... As with most amplifiers, the power dissipated within the device depends primarily on the supply voltage, the load impedance and the output modulation level. The maximum estimated power dissipation for the TDA7491LP is less than 2 W. When properly mounted on the above PCB the junction temperature could increase by 48 °C. ...
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... TDA7491LP 8 Revision history Table 10. Document revision history Date 02-Jul-2007 20-Oct-2008 29-Jun-2009 04-Sep-2009 Revision 1 Initial release. 2 Characterization curves updated Updated text concerning oscillator R and C in Electrical specifications on page 9 Updated condition for Iq test, updated value for V V maximum value, updated THD maximum value, updated ...
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... Australia - Belgium - Brazil - Canada - China - Czech Republic - Finland - France - Germany - Hong Kong - India - Israel - Italy - Japan - Malaysia - Malta - Morocco - Philippines - Singapore - Spain - Sweden - Switzerland - United Kingdom - United States of America 34/34 Please Read Carefully: © 2009 STMicroelectronics - All rights reserved STMicroelectronics group of companies www.st.com Doc ID 13541 Rev 4 TDA7491LP ...