Diode Identification Help

[Dylon Hussain]

I recently removed a malfunctioning diode (I think it's a rectifier diode because of its cylindrical shape with a sharp edge) from a power supply board and cannot find the specs on it to order a replacement. It is 5mm in length and 2mm in diameter, black with silver writing/band, and it says "GK" Followed by two "O" symbols with a "^" symbol over each. Can anyone identify this diode?

Thanks in advanced!

 

[davenn]

Hi there Dylon
welcome to the forums

who knows ... could be anything without more info
show a photo and preferably both sides of the circuit board showing where it came from

cheers
Dave

 

[shrtrnd]

I'm with davenn on this, a picture is worth a thousand words.
It SOUNDS like it might be a diode, but it could be a transient voltage suppressor of some type, or some fuseable component.
The components they're constantly coming out with keep us on our toes.

 

[Dylon Hussain]

It says D4 on the board where I pulled it from. The reason I thought it was a malfunctioning diode is because it says D (like all of the other diodes) and it had an out of limits reading when I tested the resistance, was this incorrect reasoning?

Also it's 24V 3A input, 300mA 65-105V Output

 

[shrtrnd]

Your reasoning is sound, the markings on the component are not standard. "D' on the board is standard for denoting a diode.
I'm thinking your component has proprietary markings (called 'house numbers" by most people here)
That means the manufacturer of the board asked the manufacturer of the component to mark the component with a designation that the board mfgr specified.
We've got guys on this site that are really good at identifyting circuits just by looking at them, I think you'll get some answers here that will be of more help than I can supply.
My GUESS would be one of the 1N400X series regulators, but I'd wait for more informed people here to give you their input on what you've got.
The markings on the component aren't going to help us ID it.

 

[davenn]

thanks for the pix yes definitely a diode ... cant tell where it came from on the board as you didn't mark the spot

a diode should read somewhere between really high resistance ( to 0L) in one direction and much lower in the other

it may be worth trying a 1N4007 in there and see what happens ... they are a good GP diode



Dave

 

[dorke]

By the marking on the board it is a diode,and it sure looks like one.
In my experience,the 1N400x diodes are always marked with their full part number on them.

Since it is located near T2 and Q11 it may be a fast switching power diode(shotcky?).
If so,replacing it with 1N400X is not a good idea.

what is Q11?

 

[Dylon Hussain]

It says K3564.

 

[dorke]

2SK3564 is a 900V/3A/40W power MOSFET for switching regulators.
I do believe the diode is a shotcky one,
But I can't identify it.

 

[davenn]

you still haven't shown which diode is D4

 

[dorke]

Here it is D4:

 

[Dylon Hussain]

So, do you think that STPS2H100RL would be a good guess? If:2A Vrrm:100V Tj:175C Vf:0.7V

 

[dorke]

What is the voltage rating of C9(left of D4) ?

 

[Dylon Hussain]

100nF 400V

 

[dorke]

I would go for a higher voltage,same as the cap rating.
Maybe 1N4937 not a schottky but a fast rectifier
http://www.vishay.com/docs/88508/1n4933.pdf