PHILIPS 19PFL3405H/12 - How to test Power board 715G3897 ???

[nashagui]

Hello,

I'm testing this power board and I would like how to power on without TV to meter all voltages.

In this moment only have 5.2V from Stand-by.

I need how to jump pines to power on board and see other voltages.

Some Idea ???

TV Problem... no turns on, no standby led, only 5.2V from Standby...

[dick_barton]

Re: PHILIPS 19PFL3405H/12 - How to test Power board 715G3897 ???

You have 5.2V on the 5.2V pin or on the STB pin?

[Andrew F. Ali]

Re: PHILIPS 19PFL3405H/12 - How to test Power board 715G3897 ???

Normally I'll be looking for PS-ON, BL-ON and etc. However, I can see STB and LED ON/OFF. So here's what.......
1. Disconnect all the connectors on the Pwr Bd so nothing is connected to Pwr Bd
2. From the underside of the Pwr Bd, connect a 1Kohm resistor from the STB pin to the LED ON/OFF pin
3. Plug in the AC Cord to the AC
5. Measure voltages and see if we have 24Vdc on the marked pins

BE CAREFUL OF SHOCK HAZRD

[nashagui]

Re: PHILIPS 19PFL3405H/12 - How to test Power board 715G3897 ???

Thanks.

I do it, and give stable 5.2V but not 24V.

Them, I think that PWM Controller LD7576AGR (IC901) its bad.

(Chasis TPM5.2E)

[Andrew F. Ali]

Re: PHILIPS 19PFL3405H/12 - How to test Power board 715G3897 ???

OK then...Can we get clear pictures of the underside on the main Board??

[nashagui]

Re: PHILIPS 19PFL3405H/12 - How to test Power board 715G3897 ???

I attach pics agains. thanks.

[Andrew F. Ali]

Re: PHILIPS 19PFL3405H/12 - How to test Power board 715G3897 ???

Hmmm....I think you posted these already.....This is the Power Board not the Main Board

[budm]

Re: PHILIPS 19PFL3405H/12 - How to test Power board 715G3897 ???

https://www.badcaps.net/forum/attach...6&d=1476718068
https://www.badcaps.net/forum/attach...6&d=1476718068

STB pin is the PS-ON pin, when it is high (<1V = OFF if it is active high logic) it turns on Q905 which then it turns on the switched Power MOSFET Q904 to supply the switched 24VDC to connector pins.
Notes: sometimes Philips uses active low logic, LOW = ON.