I have a mysterious sensor from medical surplus and try to identify its type. There are no markings on IC package, but I made macro shots and there are some on sensor die. So far I'm pretty sure it's Hamamatsu Phonics part based on "HPK" abbreviation. It looks like some sort of 6x6 (photodiode?) array wire bonded to integrated amplifier? Google fu does not render any results of datasheet.
Markings on die are:
HPK FS-8194
5P NEW5 PAMP_38
Any clue how to read it? Based on IDC trace routing, it can be very sensitive so I thought to ask first, before measure anything.