I've been buying IS1790 playback chips from AliExpress. These are about 1/3rd the price of the 'official' chips from DigiKey. Lately though I have been experiencing failures of around 50% of the chips that have been delivered.
The supplied chips are obviously copies, and when they work they work 100% of the original. However, the only way to check if they function or not is to solder a 28 pin SOIC down and hope for the best. A bit inconvenient if it proves faulty.
So to allow me to check the chips before sticking them down I came up with this:
It's a Tagbits UMT board wired into a 28 pin SOIC ZIF (Zero Insertion Force) socket. This lets me plug in a chip and test it without requiring me to solder it to a PCB.