32PFL3606 Fuse blow invert mosfet shorted

[siviigi]

Re: 32PFL3606 Fuse blow invert mosfet shorted

Hello people
Did you solve the problem. I have absolutely the same problem?
Any solution found?
Sivi

[budm]

Re: 32PFL3606 Fuse blow invert mosfet shorted

NC = not installed on the board, the schematic covers more than one version of the PCBA (Printed Circuit Board Assembly), the blank circuit board can be used in more than one PCBA, they just stuff the board with needed parts for the particular model of the TV as needed.
This makes it confusing because you need to see if the version of the PCBA you have has those parts installed or not.

[rpater]

Re: 32PFL3606 Fuse blow invert mosfet shorted

A other strange thing there are components on the supply that is standing in schematic as NC please see picture.

[rpater]

Re: 32PFL3606 Fuse blow invert mosfet shorted

Okay thanks for the support budm but I don't get the treshold of 12,6V, and i don't know why look at the pictures this what I get on the Vdd-s line.

[budm]

Re: 32PFL3606 Fuse blow invert mosfet shorted

How is the Vdd-s made on the supply?

See the arrows.
https://www.badcaps.net/forum/attach...8&d=1427488949

[budm]

Re: 32PFL3606 Fuse blow invert mosfet shorted

Still no luck just received and replaced the UBA IC, still only 9,6V on the supply line.

Just discovered something other strange thing, the marked resistor in the attached picture are measure in circuit 0ohm and of the pcb just 27ohm.

That is because the resistor is connected in parallel with the transformer winding which has DCR of <1 Ohm.

[rpater]

Re: 32PFL3606 Fuse blow invert mosfet shorted

How is the Vdd-s made on the supply?

[rpater]

Re: 32PFL3606 Fuse blow invert mosfet shorted

Still no luck just received and replaced the UBA IC, still only 9,6V on the supply line.

Just discovered something other strange thing, the marked resistor in the attached picture are measure in circuit 0ohm and of the pcb just 27ohm.

[budm]

Re: 32PFL3606 Fuse blow invert mosfet shorted

The startup Voltage has to reach first, 12.6V, once it is running then the running Voltage range can be as low as 10V.

[rpater]

Re: 32PFL3606 Fuse blow invert mosfet shorted

I think i have found the problem I think the IC801 (UBA2071AT) is damaged inside, therefor the supply won't start. Because when i solder the pins 9,10,14,15 to the PCB the resistances between VDD en GND of this IC drops to 44.5ohm.

When I lift this pins the resistances between VDD and GND of the IC is 1K, and when I power up the supply the voltage drops to 6V on the VDD line so i think the IC is a big damaged inside. Can any one please confirm my thought, because this is not a easy IC to get.

[Alastair E]

Re: 32PFL3606 Fuse blow invert mosfet shorted

From the PDF of the chip--

This is the positive supply of the device. The operating range is between 10 V (min) and
20 V (max) with a UVLO start threshold 12.6 V (typ).

[Alastair E]

Re: 32PFL3606 Fuse blow invert mosfet shorted

Why not Look Up on Google--That chip, and see whats the min and max VCC it is designed to run at!

IF there's supposed to be 12V and you have only 11V then it should still run correctly. Many of these chips will run from say 10V to 25V VCC....

A Volt or two Low VCC on one of these inverter chips isn't always a problem....

[rpater]

Re: 32PFL3606 Fuse blow invert mosfet shorted

Stil no luck, whit every IC and other thing removed om the VCC line still only 11,70V So i have gain 1,70V not eghough i think. So I think the supply is still in protection.

I have pull the S/B with 5V from his on standby because this is working just fine. There is 1k resistor in between. On the VCC line for the IC there is also no short.

So I think I am in a circle, and I have no clue to get out of this circle. Please take a look at the pictures I have in this state only 11,70V on the supply line for the IC.

[rpater]

Re: 32PFL3606 Fuse blow invert mosfet shorted

What has to be the DC voltage for this IC.

[CapLeaker]

Re: 32PFL3606 Fuse blow invert mosfet shorted

10v when s/b is foreced on and with the ic801 removed otherwise with ic801 in places is the voltages 0.8V

shorted all right... no wonder nothing goes.

[rpater]

Re: 32PFL3606 Fuse blow invert mosfet shorted

I will check it tomorrow thanks for the help.

[budm]

Re: 32PFL3606 Fuse blow invert mosfet shorted

10V is way too low for the ICs to run.
Check the resistance between VCC pin and GND PIN.
Some thing is loading down, it can be the IC, the zener, or bad filter caps.
See the parts I circled.

[rpater]

Re: 32PFL3606 Fuse blow invert mosfet shorted

10v when s/b is foreced on and with the ic801 removed otherwise with ic801 in places is the voltages 0.8V

[budm]

Re: 32PFL3606 Fuse blow invert mosfet shorted

What DC Voltage do you have between the IC902 VCC (PIN 6) and GND (PIN 4) when S/B is forced on?

[rpater]

Re: 32PFL3606 Fuse blow invert mosfet shorted

A other strange thing is on the feedback lines of IC909 is there also a voltage of 2.0V by a disable supply and by enable supply is there 0.9V.

And IC902 has a voltage of 3,6v on the FB line by a enable supply, I don't kwone of this normal, but the main cap is still 313v so PFC is not working. Can this have to do with the FB lines?

Only when i unplug and plug the maincord the main cap whil give 400v and the drops to 313v.