TDA1543 from China

Recently got a bunch of TDA1543's from China-based seller. I was wondering about how good these chips are, taking into account that they are not manufactured anymore, and there's a huge change to receive either completely borked chips, or chips discarded by factory testing.

So, as I usually do for all my new ICs, I set up a testbench and checked what's up with these. I was kinda pleasantly surprised to find out that they actually work. Still puzzled, I decided to check all possible sample rates that my USB sound card allows (I'm using for the test Asus Xonar U7). It turned out that chips handled without issues samplerates in the range 44.1-96 KHz, but on 176.4 KHz instead of music I heard horrifying noise. I explicitly check one old original TDA1543 made by Phillips, and handled 176.4 KHz without any issues, exactly following the specification. Of course, the original Philips TDA1543 also couldn't play at 192 KHz.

Intrigued by this finding, I tested all new chips from the batch (10x total) and found that:
- 6 of them work up to 96 KHz
- 3 of them work up to 176.4 KHz
- 1 of them is sleeping with the fishes

Well, that's not too bad. The intended usage for these DACs is for retro computing projects using samplerates below 96 KHz, and the can easily tolerate non-audiophile performance, so no big deal.

So, this was my opinion on "TDA1543 from China". Hope this helps someone.
Regards.