We are using the TAS5713 in a new design, and are gearing up for production. The prototype boards worked great except for a problem where on some power up cycles, we were unable to get audio out of the chip. Power cycling the board (sometimes several times) would correct the problem. There are a couple of interesting characteristics of this problem:
1. The power consumption of the board is the same whether or not the audio output successfully starts up. I am not sure how this is possible since we clearly aren't delivering any power to the (single) speaker (we are using PBTL mode), but there is a definitive jump in the current draw from the board whether or not there is any audio being driven out to the speaker.
2. We have dumped all contents of the TAS5713 internal registers and they are identical whether the audio output is successful or not.
I originally thought that the problem was related to the fact that on our first prototype board, we were not following the recommended sequencing of the reset and PDN lines to the TAS5713 chip. On our "production" board, I have a separate output line from our processor to control each line, but still no change.
Any ideas as to what might be responsible for this?
Thanks in advance!
Dave C