Samsung UN55ES7100 Blinking front light and no backlight - clicking

[R_J]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

Did you ever check CS802 & CS805? I wonder if the vcc supply might be too low for the ic's to operate, I would also check CP811 and CM812
The VCC is supplied by the standby circuit so even though the standby is working that secondary VCC might be low,
I'm not sure what else to look at, shorted fets ic's etc. would cause fuses to blow and they are ok.

[budm]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

Check the RESISTANCE of PFC diodes of DP804, 805 in both directions. Right now you need to get the PFC Boosted Voltage working first before going any further.

[budm]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

BTW: Spc7011f = FA5695

[nomoresonys]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

Did you try pin 20 to 17 or pin 20 to 19?

[R_J]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

Pin 19 and 17 are B5V, those are not standby voltages, B5V and B13V are only developed when the power supply's ICM801 ic is working.
PS-ON is working, confirmed in post #14
I am starting to think that VCC voltage needs to be closer to 15~16 volts, 10.7 is too low to turn on both the the main and pfc ic's
Most of the other schematics that use similar ic's are supplied by 15 volts

[budm]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

PFC IC FA5695 spec: 13V ON 9V OFF.
He needs to check the Voltage regulator circuit that feed the VCC to the PFC and the SMPS IC, just need to trace the VCC pin back to the power supply source that supplies the VCC.

[R_J]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

The source of the voltage is from DS806, CS805 is the filter, it then runs through JP810 and connects to one side of the optocoupler PC802S, where he measured 13 volts on both e&c, There will be a transistor, likely QS801 that is the regulator and it will have one or two zeners on its base, usually one 15v zener. (ZDS803 & DS807)

[budm]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

The source of the voltage is from DS806, CS805 is the filter, it then runs through JP810 and connects to one side of the optocoupler PC802S, where he measured 13 volts on both e&c, There will be a transistor, likely QS801 that is the regulator and it will have one or two zeners on its base, usually one 15v zener. (ZDS803 & DS807)

That is what I am expecting too, 15V regulator same simple topology used in many Samsung TV power supply, I expect the input to be 18 ~ 20V range to feed Collector of regulator transistor.

[R_J]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

I think I found the problem.
Have a look at the board and the icp801s pinout, but the output is on pin 8 and pin 1 is ground.

Looks more like a ICE2PCS06G
Did someone replace this PFC ic by chance????

[jason123]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

I don't believe this has been worked on R_J
Diodes DP805 is 4.56Meg and 4.34 Meg
DP804 is 4.38Meg and 4.48 Meg

CS802 and CS805 check out

[jason123]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

My apologies... 2PCS06 is the chip

[R_J]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

well that makes more sense. but I still believe the VCC is too low, on the ICE2PCS06G if the VCC drops below 11 volts the ic is OFF

If you put the board in standby, TV off, then check the voltage on JP810 and also JP811 (you can use JP843 for hot ground)
JP810 is near the standby ic, JP811 near the pfc ic.
With the board in standby, JP811 should be near 0v and JP810 should be near 20v. This should indicate if something is loading the vcc down or not

[budm]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

So where does Spc7011f as reported come? I am confused.

[jason123]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

Ok...tied connector pin 20 to gnd (shorted 20 to 16)
Now when applying power no clicking
On JP810 Started at 1.5 V and climbing up...after a few minutes it's at 6.11V and climbing slowly
JP811 the same, started at 1.2 V and after few minutes climbed to 7.09 V and still going up... after a minute more both nodes are 7.34 V and slowly climbing up. This is all referenced to JP843 (Hot GND)

Removing TV from standby, both nodes are at 162V

[R_J]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

This is starting to make no sense,

Post #16: Opto PC802S reads 12.9v and 13 v on the hot side pins

What you are telling me is when you place the board in standby you totally loose the voltage on the opto (JP810 connects DS806 to opto)
Do you still have A5V when you shorted pin 20 to ground or did it kill that also?
The reason I ask is the voltage supplied to PC802s comes directly from the standby circuit.
You must have a problem with your standby circuit and You can't be getting A5V, I bet it is also slow in coming up.
If you have almost no voltage on jp810 in standby you need to check the A5V voltage and also the voltage on CS802 (+)

[jason123]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

Continuity check between JP810 and PC802S (either pin on hot side) fails.. not a direct short- rather open

During standby, one pin on the opto is 0 v and the other is 17.3V

Measurements in #34 are rechecked & are accurate

[R_J]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

so on your board there is no connection between points A & B ?
The voltage you measured on the opto DOES make sense but 17v still seems a bit low
You said "CS802 and CS805 check out" what did you use to check them?

[jason123]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

This is embarrassing and I apologize - a bit dyslectic. I was taking the measurement on J810 not JP810
Yes, there is a connection between A / B on your image.

During Standby, JP810 is reading 17.5V. JP811 as described above, in standby starts at 1.x V then goes up

CS802 and CS805 - DC impedance in the Meg Ohms. ESR is less than 1 Ohm. Capacitance matches the value labeled 11uF and 46.3 uF

[R_J]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

That voltage on jp810 should come right up, It is possible the A5V output caps are weak, CS854/851 and might be effecting all the voltages coming from the standby circuit
In standby, jp811 should not really have any voltage, a small amount 1v can be ignored as that circuit is off like it should be in standby
If you take the board out of standby, that voltage on JP810 should be 15v and the pfc ciruit will run. but it seems the standby circuit can't supply it.
Check that RS801 is ok (it should be a short) I can't see it being open but maybe it went high in value?

[jason123]

Re: Samsung UN55ES7100 Blinking front light and no backlight - clicking

JP810 comes up to 17.5V fairly quick. It drops to 13.16V when tv is turned on. RS801 is reading 0.00 Ohm