SGTL5000 minimum SYS_MCLK frequency

[hlro1]

What is the minimum SYS_MCLK in slave mode (not using PLL, synchronous mode)?

Table 8 shows that if Fs=8kHz, SYS_MCLK can be as low as 256 * 8000 = 2.048MHz. I can't however, communicate with the SGTL5000 over I2C at 2MHz SYS_MCLK. It seems that SYS_MCLK has to be at least 7MHz before the SGTL5000 is working.

Can someone from NXP state what is the minimum for SYS_MCLK? If it is higher than 2.048MHz then table 8 is incomplete.

[JozefKozon · Accepted solution]

Dear Royan,

yes, that is correct. The SYS_MCLK clock can take clock from 8MHz to 27MHz. It looks you are lucky to have a chip, that works with even lower frequency of 7MHz, but from the datasheet the minimum SYS_MCLK frequency must be at least 8MHz. 

With Best Regards,

Jozef

[hlro1]

Dear Jozef,

Thanks for your swift reply. Noted about the frequency.

Just my opinion that the datasheet should make a note about Table 8 that only Fs that results in SYS_MCLK above 8MHz are applicable for synchronous MCLK. Also, the datasheet could clearly state (e.g. in table 3) SYS_MCLK range.

Best regards,

Royan