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Electronics => Projects, Designs, and Technical Stuff => Topic started by: 001 on December 05, 2018, 12:50:06 pm

Title: How diode, zeners and LED tester works?
Post by: 001 on December 05, 2018, 12:50:06 pm

Hi!

Is diode and LED testers a sort of current source or voltage source?

I`m looking for simple project to test my LEDs and zeners

Title: Re: How diode, zeners and LED tester works?
Post by: Zero999 on December 05, 2018, 05:12:00 pm

They'll be constant current sources or perhaps the cheap ones will just use a resistor.

What voltage range zeners do you want to test? Most diode testers have an open circuit off under a fer volts, so aren't much good for testing the reverse breakdown voltage of zener diodes.

Title: Re: How diode, zeners and LED tester works?
Post by: AngraMelo on December 06, 2018, 04:12:07 pm

Usually constant current
here goes a project that I build and works like a charm!

https://www.youtube.com/watch?v=7buNHf6HoDw (https://www.youtube.com/watch?v=7buNHf6HoDw)

Title: Re: How diode, zeners and LED tester works?
Post by: queennikki1972 on September 22, 2019, 03:35:48 pm

I built this version with a transformer, its overkill (one of my first projects, didn't know any better) but does the job for all zener diodes up to 27v....