I bought tgis cheap bluetooth receiver that has a chip #AC1805E88767 or something like that with symbol of PI(3.1416) on it? I tried to search about this IC but nothing comes up. I tried to take a photo but the chip is very small. Does any of you know about this chip?
you might have some luck if you look up the FCC ID of the device on the FCCs web site. sometimes the documents filed for FCC certification contain info about the ICs manufacturer, and the part number. once in a while, they even file a schematic with the cert application. other than that, you re probably shooting in the dark. a lot of custom ICs in cheap stuff is nearly undocumented.