TPA2031D1: Input resistance

Naizeng Wang

Part Number: TPA2031D1

Hi team,

I can't understand why input Z is equal to the external resistance. Because you can see that the input impedance is 150kOhms in datasheet.

Could you please give some comments about that?

Br,

Naizeng Wang

over 4 years ago

0 Luis Fernando Rodriguez S. over 4 years ago

TI__Guru* 84915 points

Hi, Naizeng,

I think there could be a misunderstanding with the 150Kohm resistor. As shown in the block diagram ( https://www.ti.com/lit/ds/symlink/tpa2031d1.pdf#page=4 ), this resistor corresponds to the feedback resistor of the input amplifier. The input impedance in the amplifiers is always measured from the input signal to the amplifier terminals. So, it is correct to asume that the input Z is equal to the external resistor.

Best regards,
Luis Fernando Rodríguez S.

Audio

Audio forum

TPA2031D1: Input resistance