LM4755: What is done with INA and OUTA pins if unused?

Hi, Shawn,

Normally, the analog inputs should be AC-coupled to GND and the analog outputs should be left floated when they are not used. Could you please share your circuit schematic just to verify that everything is correct?

Thank you.

Best regards,

Luis Fernando Rodríguez S.

See attached circuit

INA=GND,OUTA=OPEN ,Result: IC heats up (Current beyond 200mA at VDD=24V)

INA=GND Via 0.1Uf,OUTA=OPEN (as per below circuit)- IC heats up (Current beyond 200Ma at VDD=24V).

INA=OUTA=GND= IC heats up (Current beyond 200Ma at VDD=24V)

INA=OUTA=BIAS Pin-IC does not heat up (Less than 30mA)

For the 4th Condition-

Bias pin voltage is going down to 1.53V instead of Half VDD (+12V).

LM4755_unused pin schematic.docx

Hi, Shawn,

I replied in a different thread. Could you take a look at these questions, please?

https://e2e.ti.com/support/audio/f/6/p/861498/3188060#3188060

Let me know if you have comments on this.

Best regards,
Luis Fernando Rodríguez S.

Hi, Shawn,

Excuse me, do you have a feedback on this issue?

Thank you.

Best regards,
Luis Fernando Rodríguez S.