I'm working on reverse engineering a PCB (no documentation by manufacturer). I've identified all the other chips on this board but this one refuses to give up any google-able info. Are there any resources that can help me identify what kind of chip this is?      ______________D1 --|O    ATH 330  |--?D2 --|              |--VssVss--|     50?L  8  |--D4GND--|     3U49758  |--D5      --------------D1, D2, D3 and D4 pins are connected to a 5x2 grid of test points which I've soldered a header into. Vss is connected to the Vss of a PIC32MX695F512H microcontroller.Let me know if I can provide additional info to assist this process.
Identifying an unknown chip on a PCB
hardware;embedded;pcb
The markings look like an Atmel part (it starts with AT, which is common for Atmel parts). Given the size of the chip and context which you provided, I figured it was probably a serial EEPROM. Looking through Atmel's serial EEPROM datahsheets, your mystery chip is almost certainly an Atmel AT25128B-SSHL SPI EEPROM, which matches your chip's product markings and pinout.According to the AT25128B datasheet, the first line should be ATHXXX, where XXX is a three digit date code. In your case, ATH330 means it was made in the 30th week of 2013.The second line contains the product's truncated part number (truncated part numbers are used when the entire part number is too long to fit on the package) and country of assembly. The truncated part number for the AT25128B is 5DBL, which from the picture looks reasonably like what is printed on your chip, and the trailing 8 identifies the country of assembly (I don't know what country 8 corresponds to, but its probably somewhere in Asia :)).The last line is the Atmel lot number.