PCM1861: MD2/MD5 input High level at NO IOVDD

Toshiro Imi

Part Number: PCM1861

Hello,

Our customer has a question whether PCM1861 will be damaged or degraded with inputting MD2, MD5=3V at NO IOVDD power supply. Could you let him know if PCM1861cause an issue in such an application use case ? Does it make MD2, MD5 to IOVDD ESD diode conduct in this condition ?

It must be appreciated if you can share MD2, MD5 input equivalent circuit with him.

best regards,

over 2 years ago

0 Daveon Douglas over 2 years ago

TI__Mastermind 27790 points

Hi Toshiro,

What is the current flow into the MD2,MD5?

Regards,

0 Toshiro Imi over 2 years ago in reply to Daveon Douglas

TI__Expert 7360 points

Hi Daveon,

Thank you for your reply. But the customer does not have the current number. Could you tell us the max current that can allow to be flowed into MD2, MD5.

best regards,

0 Daveon Douglas over 2 years ago in reply to Toshiro Imi

TI__Mastermind 27790 points

Hi Toshiro,

The max current through the pin is 5mA, if exceeded the ESD diodes will clamp. (10.1.5 of d/s)

Also, the d/s doesn't explicitly state any degradation will occur, however this condition violates the power supply sequence highlighted in 11.4 of d/s, requiring supply to all 3 rails before fade in sequence of audio data. So short answer, I recommend power supplies stable before any analog input.

In addition, if AVDD or DVDD supply is available, you can tie IOVDD there. (10.2 & 11.7 of d/s)

0 Toshiro Imi over 2 years ago in reply to Daveon Douglas

TI__Expert 7360 points

Hi Daveon,

Thank you very much.

It sounds his application may be ESD diode clamp use case. Based on this, I will replied as follows.

1. the customer should be limit input current less than 5mA.

2. the customer should also keep power up sequence as described in 11.4 of the datasheet.

best regards,

Audio

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PCM1861: MD2/MD5 input High level at NO IOVDD