Samsung BN44-00214A Power Supply for LN32A450C1DXZA

[kenmoe]

Re: Samsung BN44-00214A Power Supply for LN32A450C1DXZA

that voltage is when the resistor is in place which means it should be powered on but it's not

[nomoresonys]

Re: Samsung BN44-00214A Power Supply for LN32A450C1DXZA

that voltage is when the resistor is in place which means it should be powered on but it's not

ok, forgot you jumpered it.

[nomoresonys]

Re: Samsung BN44-00214A Power Supply for LN32A450C1DXZA

Ok, til you get 380 at the filter cap, the powersupply will not work right.

[nomoresonys]

Re: Samsung BN44-00214A Power Supply for LN32A450C1DXZA

http://www.shopjimmy.com/samsung-bn4...upply-unit.htm pic. so it's right on this page.

[nomoresonys]

Re: Samsung BN44-00214A Power Supply for LN32A450C1DXZA

Look closely at CM808, any bulging of the sides or leaking? take a good look at CP801 too.

[nomoresonys]

Re: Samsung BN44-00214A Power Supply for LN32A450C1DXZA

https://www.youtube.com/watch?v=ASMOVbOZac0 Well hell just do this then, couldn't hurt.

[budm]

Re: Samsung BN44-00214A Power Supply for LN32A450C1DXZA

that voltage is when the resistor is in place which means it should be powered on but it's not

OK, lets verify if the PFC diode DP801 is OK or not by checking the RESISTANCE in both direction of that diode.

[kenmoe]

Re: Samsung BN44-00214A Power Supply for LN32A450C1DXZA

Removed one leg of DP801 and checked resistances.

Black lead to Cathode - 1.5M ohm then slowly climbed
reverse - open line

[budm]

Re: Samsung BN44-00214A Power Supply for LN32A450C1DXZA

Well, I was hoping that it will be just the bad diode for the PFC, so now we need to dig deeper into the circuit. You will need to find out if the PFC ICP801S is getting the switched Voltage at VCC at pin 8 for it to run or not.
You will have to flip the board over while making the live Voltage test in the hot deadly side of the circuit, the GND ref. point for your meter will be the negative leg of the main filter cap.
See the diagram for details. The IC is very small SMD so make sure you do not let the probe slipped on you and do not touch anything with your body or your hands.

[kenmoe]

Re: Samsung BN44-00214A Power Supply for LN32A450C1DXZA

I am getting a steady 9v at VCC pin 8 on ICP801S

[budm]

Re: Samsung BN44-00214A Power Supply for LN32A450C1DXZA

9VDC is too low, the turn on Voltage is 12.5V (Typ.) so you need to check the Voltage between:
GND and the Collector of QB802.
GND and Base of QB802.

Based on the schematic, the VCC pin should have around 15VDC.

[kenmoe]

Re: Samsung BN44-00214A Power Supply for LN32A450C1DXZA

Checked the voltages of QB802:
GND and Collector -40.2v
GND and Base steady -54.6v

Should this voltage be negative voltage

[budm]

Re: Samsung BN44-00214A Power Supply for LN32A450C1DXZA

That looks like you are using the wrong GND, you are working in the HOT side so the negative leg of the main filter cap is your GND ref, same way you use for making the measurement of the VCC pin.