PCM6240-Q1: Use the OPA1637 differential signal input to the PCM6240-Q1

You can AC Couple the output of the OPA6137 Chip to the PCM6240.

Alternatively you can also direct couple the outputs of the OPA device to the InP and InM pins. The Output common mode of the OPA Device can be set to 7V DC and its vcc set to 15V

Hi TI Team

May i ask the OPA6137 is PRE-AMP right? it can be use to backend design of AMP? have any concern? If OPA6137 design at backend design of AMP, it will cause OPA6137 damage?

Sorry is OPA1637 

In this case the OPA6137 will act like a pre amplifier to the PCM6240. Can you please let me know where the OPA6137 Input is coming from?

Hi Sanjay 

The OPA1637 input is coming from TAS6424E-Q1 or TAS6584-Q1 

Why do you need a preamplifier here? I feel you can directly connect the output of the TAS6424 to the PCM6240  provided the input signal level on the PCM6240 is within its operating limits 

Hi Sanja

Because, our structure from TAS6424 output the one channel of power is 30W, so Vo is 15.5V, and  it can use the dividing resistor to reduce the voltage and output to the PCM6240 ?  (use the differential signal)?

Yes but you can use a single resistor and capacitor in series (From Vo+ and Vo- of Amp )from the audio amp output to the ADC  differential input.

The External Resistor and the input impedance of the ADC shall divide down the signal to the allowe levels of the ADC.

I feel that you dont need an additional op amp 

Hi Sanjay

As below is our structure, So your suggestion is not to need the OPA , It use an external divide resistor and AC coupled capacitor? May i ask, if use the external divide resistor it will effect front-end R-load resistance value? (R-load is 4Ω) 

The Resistance you will use from the Power amp output to the ADC will be several K in value. Therefore it will not place any increased load  across the amplifier output which is already driving 4 ohms