TAS6424-Q1: TAS6424-Q1 MUTE pin questions - possible to get MUTE pin status over I2C?

William Smith

Prodigy 20 points

Part Number: TAS6424-Q1
Other Parts Discussed in Thread: TAS6424

I did not find in the specs anything about reading the status of the MUTE pin over I2C.

Is it possible to read the MUTE status over I2C? And is it possible to somehow override the MUTE using I2C

over 2 years ago

0 Gregg Scott over 2 years ago

TI__Mastermind 45085 points

Hi,

The hardware MUTE cannot be overridden in I2C. The hardware MUTE and the I2C MUTE is an OR function. The output status of each channel can be seen in register 0x0F.

Regards,
Gregg Scott

0 William Smith over 2 years ago in reply to Gregg Scott

Prodigy 20 points

I am currently reading an unconfigured TAS6424 and I am getting the default value described in the datasheet, 0x55. (Hi-Z state for all channels) The reason why I am asking, is that I want to validate this in a system where the MUTE is controlled by a separate microcontroller and is not currently pulled high.

0 Gregg Scott over 2 years ago in reply to William Smith

TI__Mastermind 45085 points

Hi,

This is not clear. Are you reading register 0x0F while the MUTE pin is pulled low? This will need to be verified on our bench.

Regards,
Gregg Scott

0 William Smith over 2 years ago in reply to Gregg Scott

Prodigy 20 points

So the MUTE pin is active low, with an internal 100K pulldown resistor. So by default it should be on MUTE. But the specs say the default value for that register is 0x55 or Hi-Z for all channels, which is what I am seeing. So I am not sure if the MUTE pin status can be read from that 0x0F (channel state) register. If all the channels were on mute, then the register should show 0xAA.

0 Gregg Scott over 2 years ago in reply to William Smith

TI__Mastermind 45085 points

Hi,

We will verify this for you.

Regards,
Gregg Scott

0 Gregg Scott over 2 years ago in reply to Gregg Scott

TI__Mastermind 45085 points

William,

This was testing in our lab. We had the device in play mode, with the mute pin de-asserted (unmute). Read register 0x0F the value was 0x00. This tells us the device is in play mode. The mute pin is then asserted (mute mode). We read register 0x0F the value was 0xAA. This properly indicated that all 4 channels are in mute mode.

If your device is in Hi-Z mode, this will override the MUTE function. The device cannot move to the MUTE state, if it is in Hi-Z.

Regards,
Gregg Scott

Audio

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TAS6424-Q1: TAS6424-Q1 MUTE pin questions - possible to get MUTE pin status over I2C?