Multiplexed Audio ADC - PCM1864/5

Vidya Vasudevan

Prodigy 155 points

Other Parts Discussed in Thread: PCM1864

Is it possible to configure 2x PCM1864/5 multiplexed to support 16 Microphones on I2S DOUT (single channel)?

Assuming: 48KHz fs, 24bit word size

over 9 years ago

0 Luis Fernando Rodriguez S. over 9 years ago

TI__Guru* 84915 points

Hi, Vidya,

The PCM1864 is a 4-channel Audio ADC. In TDM mode, this device is able to send all the channels data by the I2S DOUT. So, 2xPCM1864 won't be enough to support 16 microphone data. You will require 4xPCM1864.

Best regards,
Luis Fernando Rodríguez S.

0 Vidya Vasudevan over 9 years ago in reply to Luis Fernando Rodriguez S.

Prodigy 155 points

Thank you Luis!

Is there anything specific I would need to ensure for perfect Sync between all ADCs? Would you recommend a certain architecture for interconnects? ADC as a master for BCLK/LRCLK?

Similar to TLV320, where I had one ADC as the master driving the others.

Vidya

0 Luis Fernando Rodriguez S. over 9 years ago in reply to Vidya Vasudevan

TI__Guru* 84915 points

Hi, Vidya,

Please ensure that the power up sequence of datasheet below is respected. It is necessary to have the PCM correctly configured. Basically in our TLV320 devices, we only recommend to have all the blocks synchronized and power up the ADCs while the clocks are active. This ensures that all the devices start working at same time.

www.ti.com/.../pcm1864.pdf

Best regards,
Luis Fernando Rodríguez S.

Audio

Audio forum

Multiplexed Audio ADC - PCM1864/5