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ADAU1701 schematic issue when using user defined library

Question asked by Sam.S on Jul 21, 2017
Latest reply on Aug 2, 2017 by galvinpjg

Dear Sir,


Our customer found a strange issue on ADAU1701.

When they change the selector (red circle), “POP” noise will output from speaker.

1)     DSP input is DC block, so it should no noise from input.

2)     Selector output connect to nothing, it should not affect the output


ADAU1701 pop noise issue_schematic_main


The issue is like below movie link:

this movie


Even through we have suggested they to using "Clickless SW Slew", still have the problem.


"Clickless SW Slew" conponent 


Our customer got the schematic from their end customer, found there have user defined library components in the schematic as below:


User defined components

If bypassed the Xover3 (Crossover) and EQ2 (user defined EQ), then the problem is fixed;

Otherwise, even though just change the DC input entry to select the Volume Table, the pop noise still happened.


Pop noise happened even though change the DC value to select the Vol. table


Our customer need us help them to solve the problem, do you have any idea on this issue?


Thank you!