How to test diodes

[RyanElectro]

Hey LPF community,

Was looking into how one can test a range of diodes in a simple manner. So say, we have 20 diodes and would like to test them in a quick and simple way at a set current, what's the best way to do so?

Here's what I've been thinking::
Press diode into aixiz module with lens; Wrap up the wires (w/o solder) on the diode to linear driver set at X current; wires from the driver to ends of 2 batteries (how to hold these 2 batteries together?).

But this way, I'll have to depress the module each time to swap out the diode. Or maybe I could just leave them in the modules I guess, but I'll need 20 modules then lol.

What are better ways to do this? Is there a device I can just put my diode in, that will run a set current and test it? Share some ideas

 

[lasersbee]

You will need to have this duplicate Thread deleted....

Jerry

 

[sesam]

Are you going to do this many times ?
If so you should get a copper heat zink for the diode, divide it in two parts
so you easily can put in and take out the diodes.
(or A copper plier)
Instead of soldering you can use one of the small cable-connector that fits the legs
on the diode, and It will be easy to take it out and put another one in.

And last. if you dont want to use a driver, by a power supply where you can regulate the current!

Thats what I would do.

 

[RyanElectro]

Are you going to do this many times ?
If so you should get a copper heat zink for the diode, divide it in two parts
so you easily can put in and take out the diodes.
(or A copper plier)
Instead of soldering you can use one of the small cable-connector that fits the legs
on the diode, and It will be easy to take it out and put another one in.

And last. if you dont want to use a driver, by a power supply where you can regulate the current!

Thats what I would do.

Hey thanks, that's really useful information.

For connecting wires on the pins of diodes, can't I just wrap the ends of wires around the pins? That would work right?

Do you know of a good place to buy regulating power supplies? Also, will I need AC-DC or DC-DC?

 

[sesam]

Power supplys, I know where to by in Sweden:thinking: but that want help you.
But I know I have seen some nice one's here on the forum so make a search for them!

And about attaching the wires directly, Yes you can but its a small space between the pins and it's easy to short circuit, but it's better than soldering I think, I have killed a diode recently when I forgot to use a small plier on the pin I was soldering, usually I use one of those to dissipate the heat away.

 

[Blord]

If you want to test the diode with a temporary setup, use test hooks to make contact with the diode pins. Much better than loose wire wrapped around the pins and no risk to short circuit.

 

[GAtkins]

DC Power Supply - Linear Power Supply - Mastech REGULATED VARIABLE DC POWER SUPPLY HY3006D 30V 6A New Model (Powered by CubeCart)

Glenn

 

[rocket689]

I have a heatsink that I custom machined to use for diode testing.
I machined a m9x0.5 thread in the front of the sink for a collimating lens.

I machined a 5.8mm pocket in the tail of the sink and made a thumb screw that will hold the diode into the pocket.

I solder leads super-quickly (within a split second) to the diode so there is a solid connection.
I then slip pieces of heatshrink over the joints and put the leads through the hollow thumbscrew.

I use a regulated DC power supply to power the diodes and meter the output with a LPM.

Hope that helps! :wave:

 

[tsteele93]

Along these lines, can I turn on a PSU and set the voltage to the correct vf for the diode with current set to virtually zero, short the leads, then connect them to the diode and ramp up to test the diode to see if it is working?

If so, what V should I set the PSU at for various diodes?

Thanks!

 

[Cyparagon]

Which PSU? Some are not regulated very well - it is kind of risky if you're using a cheap Chinese one that hasn't been scoped. You cannot have constant current and constant voltage at the same time. Power supplies default to constant voltage. If the current rises to the current limit you have set - then it switches to constant-current. Here's what I do:

1. Set the voltage to slightly over what you expect it to run at. This should ensure it operates in constant-current at all times.
2. Turn the current down to zero. This should lower the voltage output.
3. Be sure the voltage is near zero or at least below Vf - some supplies will float up.
4. Connect the diode.
5. Raise the current.

Sometimes I'll just set them both to zero, connect everything, crank the voltage right up, and turn the current up slowly. As long as it is above Vf, the voltage setting isn't crucial since it will be operating in constant-current anyway.

 

[Fiddy]

But this way, I'll have to depress the module each time to swap out the diode. Or maybe I could just leave them in the modules I guess, but I'll need 20 modules then lol.

Didnt you spend $1500 in parts? wouldn't you have at-least 20 modules :thinking:

 

[RyanElectro]

Didnt you spend $1500 in parts? wouldn't you have at-least 20 modules :thinking:

This was before wayy back... few weeks before my first build? :S what are you saying lmao!

 

[Fiddy]

Well your attempted to run a 'Laser Pro Shop' so i would of thought you had some modules lying round, im not a seller and ive got more than 20 modules lying round...

 

[RyanElectro]

Well your attempted to run a 'Laser Pro Shop' so i would of thought you had some modules lying round, im not a seller and ive got more than 20 modules lying round...

This was back then over a month ago thread that I had like 2-3 modules.

If you're wondering my most modules are used by now, I have 5 copper modules + 40 coming from the GB.

But pointless to keep stock for my BETA shop, I was providing a service so I bought the parts on order.

However, I'm going to be building some nice C6's soon, the build I'm super comfortable with, and have some nice internal goodies in it. I'll keep 3 in stock then and sell those as I think it's better like that.