TPA2011D1: about D-class Amplifier

Satoshi Okamoto

Part Number: TPA2011D1

Hello;

I designed a new board.
I used "TPA2011D1YFF" for audio circuit, audio input is single end.
When single end, startup unbalance occurs with differential output.
When unbalance of startup occurs, pop noise appears.

Is there countermeasures against unbalance at startup?

Regards,

-satoshi

over 8 years ago

0 José Luis over 8 years ago

TI__Mastermind 20085 points

Hi Satoshi-san,

Is the pop noise happening when the device is turned on or if the shutdown mode is activated?

Best Regards
José Luis Figueroa
Audio Applications Engineer

0 Satoshi Okamoto over 8 years ago in reply to José Luis

Intellectual 505 points

Dear José

Pop noise comes out when the power is turned on.

5 V is powered before EN(enable).
There is no change in output when EN(enable) is set to H level.
It is considered that unblance of output occurred when operating H bridge.
After that, normal sound is output.

Regards,

-satoshi

0 José Luis over 8 years ago in reply to Satoshi Okamoto

TI__Mastermind 20085 points

Hi Satoshi,

Are you sending an input signal before turning on the device? if so, It is necessary to wait that the device turns on completely before sending an input signal.

Best Regards
José Luis Figueroa
Audio Applications Engineer

0 Satoshi Okamoto over 8 years ago in reply to José Luis

Intellectual 505 points

Dear Jose

Signals are input after turning on the power.

It always occurs when Enable is set to H level.
This is considered to be a characteristic of the device.

I avoided this by adjusting on the input side.

Regards,

-satoshi

0 José Luis over 8 years ago in reply to Satoshi Okamoto

TI__Mastermind 20085 points

Satoshi-san,

This device has a start-up time of 4ms, so you should wait this time before you send an input signal.
The pop noise happens in single-ended configuration due to the discharge time of the input capacitors is different. The pop noise could be reduced if the input capacitor value is lower, perhaps you could try with 0.1uF. Besides, the input signal should be sent with the lowest volume in the beginning and after can be increased.

Best Regards
José Luis Figueroa
Audio Applications Engineer

0 Satoshi Okamoto over 8 years ago in reply to José Luis

Intellectual 505 points

Dear Jose

Thanks for the advices.

Pop noise is reduced by reducing the input capacitor.
The input capacitor was chosen to be 0.01 uF.
It is impossible to eliminate pop noise, but it was achieved to reduce it.

Best Regards,

-satoshi

Audio

Audio forum

TPA2011D1: about D-class Amplifier