Features of PCM1860

Hi,

1. Yes you can use this device with just BCK, LRCK, and DOUT. The rates available in this mode are specified in table 11 of the data sheet.

2. No, only software controlled PCM186X devices can implement the AGC features.

Justin

Hi Justin

Thank you for your reply.

I have an additional question.

>1. Yes you can use this device with just BCK, LRCK, and DOUT. The rates available in this mode are specified in table 11 of the data sheet.
I noticed that table 10.12.4 of the data sheet shows ADC Slave mode needs External XTAL/MCLK input for PCM1860/2/4.

Do you mean both of XTAL and MCLK are not required for I2S communication in PCM1860?

>2. No, only software controlled PCM186X devices can implement the AGC features.
You mean we can control AGCs independently in software controlled PCM186X, don't you?

regards

Hi,

1. Do you mean both of XTAL and MCLK are not required for I2S communication in PCM1860?

That is correct, for the clock settings specified in table 11, you can run the PCM186X with just BCK and LRCK. The internal PLL will generate the necessary internal clocks to operate.

2. You mean we can control AGCs independently in software controlled PCM186X, don't you?
The AGC is not available in the PCM1860 or PCM1861.

Justin

Hi Justin,

Thank you for your reply.

Could you please show me a little more about following comment?

>That is correct, for the clock settings specified in table 11, you can run the PCM186X with just BCK and LRCK.
>The internal PLL will generate the necessary internal clocks to operate.

Table 11 indicates Auto PLL BCK Req in Slave PLL mode, but table 10.12.4 (Page 29) shows that PCM1860 is not a device supporting slave PLL mode. So I think table 11 may not be applied to PCM1860 device. Is that correct?

>The AGC is not available in the PCM1860 or PCM1861. 

Thanks, I see.

Should we set LINK (Page0/register 5)  to "0" if we realize AGC independently by each channel in PCM1862?

(Because PCM1862 has 2 channel ADCs)

regards,

The table in 10.12.4 states that the PLL does not need to be configured for the PCM1860/1. This isn't saying that the PLL can be used, just not manually configured. Table 11 shows what clocks will be automatically recognized.

Justin

Hi Justin,

Thank you for your quick reply.

Can I have a comment following also?

>Should we set LINK (Page0/register 5) to "0" if we realize AGC independently by each channel in PCM1862?

I suppose to use AGC feature like TLV320ADC3101.
TLV320ADC3101 has two AGC and AGC is controlled by each channel.

regard,

Hi,

I would suggest you do not set LINK, this is because when the channels are linked, they will follow channel 1 gain setting. However, the AGC will still affect individual channels. So if the AGC lowers channel 2 because it is clipping, channel one will not be effected. If channel 1 is reduced from AGC when linked, channel 2 will change.

For this reason I suggest when using AGC that the gains not be linked.

Justin