Philips CD608 digital output broken

[emanue]

Hi, i have an old Philips CD608 that works perfectly except digital output.
Connected to DAC, that output is completely mute. Analog output instead is working fine.
Looking at service manual, this is the interesting part:

SPDIF connector is on the lower side (BU2 -3 and BU2-4).
Service manual helps giving indication for troubleshhoting, as follow:

So i checked 3650 fuse resistor and it's ok. VDD is 4.9 V directly on PCF3523P pin 16 and 8.
Circuit 6568 is a BC848 transistor, It's not open and not shorted.
For testing i removed 3659 resistor to bypass any kind of Kill mute signal, but nothing changed with transistor base opened.
Bridge 3881, 3880 and 3889 are ok and not interrupted.
Resistor 3653 is 679ohm, so it's ok

Any other suggestion?

Are there any chances that the PCF3523P is not the culprit?
Thank you
Emanuele

 

[Markw4]

Only way to be sure if PCF3523P is good or bad might be: (1) measure its all inputs with scope, measure all its outputs, compare results with its datasheet specs; or (2) substitute a known good chip into the circuit.

 

[emanue]

Only way to be sure if PCF3523P is good or bad might be: (1) measure its all inputs with scope, measure all its outputs, compare results with its datasheet specs; or (2) substitute a known good chip into the circuit.

Hi Markw4, yesterday i measured output with scope, and seen a very bad square wave in idle at digital output.
Today i will check other input, output and oscillator quartz.
It seems that i was not able to find PCF3523P datasheet, do you have it?

Thanks.
Emanuele

 

[Markw4]

Don't have a datasheet for it myself.