Philips wakeup light broken speaker, AMP broken? +unknown IC mystery.

[tjeulink]

Hi there! i am trying to repair an philips wakupe light. the lamp dimming was broken before, it could only remain powered on. eventually i managed to repair it by replacing the TRIAC. but in the meantime i broke the audio it seems. my guess is that i either shorted the speaker pins for a long while, or accidently hooked up the transformer to the speaker pins and the speaker to the power pins  . the transformer is 9Vac. When i turn it on i can hear the speaker pop, but nothing else. everything else about hte wakeup light works fine, it indicates that it should be making sound but it doesn't. Bellow some pictures!

This is the chip i suspect is broken, its a APA0711 if i'm not mistaken. here's a link to its spec sheet.


This is a picture of the entire PCB where i point at the speaker pins.


Top side of PCB pointing at speaker pins:


This is a picture of the mystery IC, i think its what goes into the APA0711, i am not sure though.


Here is some pictures of the mystery chip under different lighting and with some whiteboard marker to see if i can get anything visable that way, works somewhat but i can't seem to find anything about it.



Does anyone know what the best way to diagnose this would be? or is this in your opinion and open and shut case? thanks for your time!

[fzabkar]

PT2257, Princeton, electronic volume control IC, dual channel, 3V - 10V, SOP-8:
http://www.princeton.com.tw/Portals/0/Product/PT2257.pdf

[tjeulink]

PT2257, Princeton, electronic volume control IC, dual channel, 3V - 10V, SOP-8:
http://www.princeton.com.tw/Portals/0/Product/PT2257.pdf

Ah thanks that would make sense!

[MrPeter]

Hi There.

I got kind of same issue with PCB E101438. After power lock down, it can start up. No power at all, I have check the fuse, the 4 diodes, the small transformer, but it is all dead. I don't what it could be?