Transistor identification

[Behemot]

I got troubles identificating a TO251 transistor. There is 2663, than K and 83. I found 2SK2663 but that is SMD not through-hole. High voltage may be, I don't know how this works but it is basically embedded tiny PSU for charging NiMH battery. There is input, rectified and filtered, than small transformer and after the transformer is this transistor.

It is from Philips HQ 2830 shaver, there also was burned one SMD transistor (which I think I have identified and replaced) but this seems also bad with 004 voltage drop between electrode 1 and 3. And also two SMD resistor which I have some trouble identifying, one is posibly 680 ohm, the other one who knows…

[stj]

Re: Transistor identification

2sk series would be a fet.
got any foto's off the board?

[selldoor]

Re: Transistor identification

Does it look like these?

http://www.ibuyla.com/Product/134064...ity_assurance/

They seem to think they are 2SK2663

[Behemot]

Re: Transistor identification

Yep, exactly. So 1A/900 V N-FET, good, I'll look after replacement and take the foto, maybe we'll get aproximate value of the resistors…

[Behemot]

Re: Transistor identification

Here it is. I have already replaced the SMD transistor which was burned, I identified it as some SMD NPN, replaced with BCW66H.

Now also this N-FET in question is bad and also two resistors. Resistor 1 seems like 6x0 so I will guess 680 ohm. The blue one is 4-digit but I have no idea what. It goes from GND/- of the battery to base of the NPN transistor.

[stj]

Re: Transistor identification

is the black diode o.k. ?

[Behemot]

Re: Transistor identification

Measures normal diode drop so I would say so…

[selldoor]

Re: Transistor identification

Sorry no idea - assume you have tried to clean it up.

[Behemot]

Re: Transistor identification

The resistors?

[vinceroger69]

Re: Transistor identification

please ignore

[selldoor]

Re: Transistor identification

Hi - yes the blue resistor - I guess someone somewhere will have seen this circuit but what chance on here? how about another thread with the
Philips HQ 2830 shaver in the title- might jog someones interest. May even have one in a drawer
they could look at for you.

[Behemot]

Re: Transistor identification

May be good to just rename this one?

[budm]

Re: Transistor identification

It looks like non-isolated 2-transistor switching power supply.
When that power MOSFET is shorted out, it will take many parts with it.

[Behemot]

Re: Transistor identification

I thought something like that, now I see it more clearly, ty

Would 3A/800V N-FET be OK? And do you have any idea what the blue resistor may be?

Input rectifiers seemed good, I'll check the resistor in there…

[budm]

Re: Transistor identification

The ratings looks OK.
I cannot clearly read the numbers on the resistors, are they 4 digits?
http://www.hobby-hour.com/electronics/smdcalc.php

[Behemot]

Re: Transistor identification

The black one which seems like something similar to 680 is 3 digit, so I see it is 68 ohm, not 680. The blue ones are 4 digits, yes. Unfortunately it is burned just through the print so I have no idea, I think we will have to guess it's value.

And the fusible input resistor is also bad, I'll replace it as well. Rectifying diodes all survived it.