Help identifying Sega Nomad chip

[radiokid]

Hi

Could someone please identify the following chip on my Sega Nomad, I have another Nomad and on this system this chip looks to have blown at some point. I'm getting readings of up to 20v from some of the pins, whereas on the working chip the reading are around 2.3v.

It's labelled as 5C57 or it could be 5C51, listed as part TR202. I've looked for Nomad schematics but haven't had any joy so far. What could I replace this part with?

Current symptoms of the system are, replaced 5v voltage regulator and system is getting 5v where it should be, but when I turn it on connected to TV there is no activity apart from a whining sound. The built in LCD is missing so cant test that.

[citrus3000psi]

Normally the subscript is the manufacture date code. So the marking is really just 5C. I did some looking, didn't find an exact match. But it maybe a voltage detector. Which makes since that its in a nomad. Can you tell me what each pin goes to.

[radiokid]

Normally the subscript is the manufacture date code. So the marking is really just 5C. I did some looking, didn't find an exact match. But it maybe a voltage detector. Which makes since that its in a nomad. Can you tell me what each pin goes to.

Yup I'll check later and post back, thanks for the reply.