Testing
Schottky Diode - The Right
WayTo Test
It
Schottky diode or schottky
barrier rectifiers are designed for high efficiency rectification
essential for applications like Switched mode power supplies
(SMPS), Switching regulator and etc. If you look at electronic
schematic diagram, schottky diode symbol looks the same as normal
diode. Even the shape and designed just like a normal diode. The
major differences between a normal diode and schottky diode is the
part number. Due to this, many technicians thinks that checking
schottky diode just the same as checking a normal diode. Infact
there is a right method to identify schottky diode and a suggested
way to test it.
Searching the internet for
the diode schottky part number and browsing through the
semiconductor replacement guide can quickly give you the answer
whether the component that you are testing is a normal diode, ultra
fast recovery diode or schottky diode. If you have confirmed that
the diode is a schottky diode then you you have to use the accurate
way to test it.
Set your analog multimeter to
times 10k ohm. Place the red probe to the cathode and the black
probe to the anode. You should see the needle goes up to full
scale. Reversing the probe will show some leakage which mean the
needle move up a little bit. This is a good schottky diode
characteristic when checking on it. However if you measure a normal
diode and you discovered that it has two readings then the diode is
considered spoilt and need to replace. A shorted schottky barrier
diode will show two full scale readings registered at the panel
meter.
If a technician do not know
how to check a schottky diode, he or she may think that the diode
have some leakage and need to replace. The worst part is diodo
schottky is not easy to find in the market. Searching for schottky
diode replacement will take you time and it is not necessary if you
know how to test it. The technician might just simply replace a
'normal diode' and hope that it will work. Well, the equipment will
still not work because you have replaced a working diode (schottky
diode) with another good diode! The actual culprit is still out
there and not the schottky diode.
Sometimes replacing a
schottky diode with a normal diode may cause the equipment to be
unstable especially in the sensitive circuit. The best is to
replace with original number or a specification that is higher than
the original diode. Typical part number for a schottky diode is
1N5819. Go check out this part number from your favorite search
engine and semiconductor data book.
That's it for this issue my
friend. Thank you for reading. I will send you more tips. Until
then, here's wishing you all the best in electronic
repair.

Author By : Jestine Yong, he
is a electronic repairer and a writer. For more information on
electronic repair please visit his website at : http://www.noahtec.com/electronic-repair-articles.htm
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