TDA7491LP13TR STMicroelectronics, TDA7491LP13TR Datasheet

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... Thermal overload protection ■ Externally synchronizable Table 1. Device summary Order code Operating temperature TDA7491LP - °C TDA7491LP13TR - °C March 2011 2 x 5-watt dual BTL class-D audio amplifier = 6 Description The TDA7491LP is a dual BTL class-D audio amplifier with single power supply designed for LCD TVs and monitors ...

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Contents Contents 1 Device block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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TDA7491LP 7 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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List of tables List of tables Table 1. Device summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...

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TDA7491LP List of figures Figure 1. Internal block diagram (one channel only ...

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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) 6/37 Doc ID 13541 Rev 5 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 ...

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Pin description 2.2 Pin list Table 2. Pin description list Number Name 1 SUB_GND 2,3 OUTPB 4,5 PGNDB 6,7 PVCCB 8,9 OUTNB 10,11 OUTNA 12,13 PVCCA 14,15 PGNDA 16,17 OUTPA 18 PGND 19 VDDPW 20 STBY 21 MUTE 22 INPA ...

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TDA7491LP 3 Electrical specifications 3.1 Absolute maximum ratings Table 3. Absolute maximum ratings Symbol V DC supply voltage CC Voltage limits for input pins STBY, MUTE, INNA, INPA INNB, INPB, GAIN0, GAIN1 T Operating temperature op T Operating ...

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Electrical specifications 3.3 Electrical specifications Unless otherwise stated, the results in R (load) = 8Ω Table 5. Electrical specifications Symbol V Supply voltage CC I Total quiescent current q I Quiescent current in standby qSTBY V Output offset ...

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TDA7491LP Table 5. Electrical specifications (continued) Symbol SVRR Supply voltage rejection ratio Rise and fall times Switching frequency SW f Switching frequency range SWR V Digital input high (H) inH V Digital input low ...

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Characterization curves 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 and that for the 8-Ω load uses 33 µH ...

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TDA7491LP Figure 5. THD vs. output power (100 Hz) Test Condition: Vcc =6.6V, RL= 4 ohm, Rosc =39kΩ, Cosc =100nF, f =100Hz, Gv =30dB, Tamb =25°C Specification Limit: Typical: Po =5W @ THD =10% Figure 6. THD vs. frequency Test ...

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Characterization curves Figure 7. Frequency response Test Condition: Vcc =6.6V, RL= 4 ohm, Rosc =39kΩ, Cosc =100nF, f =1kHz, Gv =30dB, Po =1W Tamb =25°C Cin = 1uF Specification Limit: Max: +/-3dB @20Hz to 20kHz Figure 8. Crosstalk vs. frequency ...

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TDA7491LP Figure 9. FFT (0 dB) Test Condition: Vcc =6.6V, RL= 4 ohm, Rosc =39kΩ, Cosc =100nF 1kHz, Gv =30dB, Po =1W Tamb =25°C Specification Limit: Typical: >60dB for the harmonic frequency Figure 10. FFT (-60 dB) Test ...

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Characterization curves Figure 11. Power supply rejection ratio vs. frequency Test Condition : Vcc = 6.6V ohm, Rosc =39kΩ, Cosc =100nF, Vin=0, Gv =30dB, Tamb =25° 500mVrms Fr = 100Hz Figure 12. Power dissipation and ...

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TDA7491LP Figure 13. Attenuation vs. voltage on pin MUTE Test Condition : Vcc = 6.6V ohm, Rosc =39kΩ, Cosc =100nF, f=1kHz, 0dB@f=1kHz, Po=1w, Gv =30dB, Tamb =25°C Figure 14. Current consumption vs. voltage on pin STBY Test ...

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Characterization curves Figure 15. Attenuation vs. voltage on pin STBY Test Condition : Vcc = 6.6V ohm, Rosc =39kΩ, Cosc =100nF, f=1kHz, 0dB@f=1kHz, Po=1w, Gv =30dB, Tamb =25°C 18/ ...

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TDA7491LP 4.2 With 8-Ω load at V Figure 16. Output power vs. supply voltage Test Condition : Vcc = 5~9V ohm, Rosc =39kΩ, Cosc =100nF, f =1kHz, Gv =30dB, Tamb =25°C Specification Limit: Typical: Vs =9V,Rl = ...

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Characterization curves Figure 18. THD vs. output power (100 Hz) Test Condition: Vcc =9V, RL= 8 ohm, Rosc =39kΩ, Cosc =100nF, f =100Hz, Gv =30dB, Tamb =25°C Specification Limit: Typical: Po =5W @ THD =10% Figure 19. THD vs. frequency ...

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TDA7491LP Figure 20. Frequency response Test Condition: Vcc =9V, RL= 8 ohm, Rosc =39kΩ, Cosc =100nF, f =1kHz, Gv =30dB, Po =1W Tamb =25°C Specification Limit: Max: +/-3dB @20Hz to 20kHz Figure 21. Crosstalk vs. frequency Test Condition: Vcc =9V, ...

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Characterization curves Figure 22. FFT (0 dB) Test Condition: Vcc =9V, RL= 8 ohm, Rosc =39kΩ, Cosc =100nF 1kHz, Gv =30dB, Po =1W Tamb =25°C Specification Limit: Typical: >60dB for the harmonic frequency Figure 23. FFT (-60 dB) ...

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TDA7491LP Figure 24. Power supply rejection ratio vs. frequency Test Condition : Vcc = 9V ohm, Rosc =39kΩ, Cosc =100nF, Vin=0, Gv =30dB, Tamb =25°C Figure 25. Power dissipation and efficiency vs. output power Test Condition : ...

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Applications information 5 Applications information 5.1 Applications circuit Figure 26. Applications circuit for class-D amplifier 24/37 TDA7491LP Doc ID 13541 Rev 5 TDA7491LP ...

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TDA7491LP 5.2 Mode selection The three operating modes, defined below, of the TDA7491LP are set by the two inputs STBY (pin 20) and MUTE (pin 21) as shown in ● Standby mode: all circuits are turned off, very low current ...

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Applications information 5.3 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 7. Gain settings ...

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TDA7491LP 5.5 Internal and external clocks The clock of the class-D amplifier can be generated internally or can be driven by an external source. If two or more class-D amplifiers are used in the same system recommended that ...

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Applications information 5.6 Modulation The output modulation scheme of the BTL is called unipolar pulse width modulation (PWM). The differential output voltages change between 0 V and +V This is in contrast to the traditional bipolar PWM outputs which change ...

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TDA7491LP 5.6.1 Reconstruction low-pass filter Standard applications use a low-pass filter before the speaker. The cut-off frequency should be higher than 22 kHz and much lower than the output switching frequency necessary to choose the L-C component values ...

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Applications information Emission tests have been performed with a 1-m length of twisted speaker wire with ferrite beads. Changing the type of the ferrite bead requires care due to factors such as its effectiveness in the EMC frequency range and ...

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TDA7491LP 5.7 Protection functions The TDA7491LP is fully protected against undervoltages, overcurrents and thermal overloads as explained here. Undervoltage protection (UVP) If the supply voltage drops below the value page 10 the undervoltage protection is activated which ...

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Applications information 5.9 Heatsink requirements Due to the high efficiency of the class-D amplifier a 2-layer PCB can easily provide the heatsinking capability for low to medium power outputs. Using such a PCB with a copper ground layer of 3 ...

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TDA7491LP 5.10 Test board Figure 37. Test board (TDA7491LP) layout Doc ID 13541 Rev 5 Applications information 33/37 ...

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Package mechanical data 6 Package mechanical data The TDA7491LP comes in a 36-pin PowerSSO package with exposed pad down (EPD). Figure 38 below shows the package outline and Table 9. PowerSSO-36 EPD dimensions Symbol Min A 2.15 A2 2.15 a1 ...

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Figure 38. PowerSSO-36 EPD outline drawing h x 45° ...

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Revision history 7 Revision history Table 10. Document revision history Date 02-Jul-2007 15-Oct-2008 23-Jun-2009 04-Sep-2009 23-Mar-2011 36/37 Revision 1 Initial release. 2 Updated characterization curves. Updated text concerning oscillator R and C in Electrical specifications on page 10 Updated condition ...

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... TDA7491LP Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...