the IC not outputting any audio signal. approximately one out of every 128 times the IC is enabled, or at the same frequency when certain blocks in the IC are enabled/disabled.
DAU have recently found a bug that affects many of the codecs and SigmaDSPs that we have designed in the past couple of years. This bug is in a dejitter circuit that we use on these products to clean up the serial port clocks when the IC is operating in both master or slave modes. On the affected ICs that include converters (all except the ADAU144x), the bug will manifest itself by the IC not outputting any audio approximately one out of every 128 times the IC is enabled, or at the same frequency when certain blocks in the IC are enabled/disabled. The affected products include:ADAU1381ADAU1382ADAU1781ADAU1361ADAU1761ADAU1442ADAU1445ADAU1446ADAU1461ADAU1961On the ADAU144x, the frequency of occurrence will be much less than 1/128 – to the point that it’s unlikely that a customer will ever see it. We of course still recommend that the work-around is implemented for the ADAU144x parts, because that will ensure that they never see the error. It’s important to note that this bug is something that could appear on any individual IC; it’s not a case where one chip will either have it or not have it. The good news is that we understand the cause of this issue and have workarounds that users can implement in their initialization code. This should not require any hardware redesign. The work-arounds depend on whether the IC is being used in master or slave mode; we have different work-arounds for each case. The bug is described in the attached errata document, which can be sent to anyone who is working with the affected parts. We are working on putting this explanation and the work-arounds in the datasheets for these parts, so that any future user of these ICs will see this.