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Is the reverse voltage on all LEDs always 5v or more? Answered

I have a bunch of LEDs (mainly 0603 and 5050 smd, 3mm, and 5mm - all colors).  Most of them don't list a reverse voltage.  Those that do say 5volts.  My question is, do any LEDs have less than 5v reverse voltage?  Is it possible to accidentally kill them by connecting backwards to a 5v power supply?  Should I put resistors on both the positive and negative to protect them (would that even work)?  Thanks.


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7 years ago

I can't give a guarantee for it, but as much as I know, 5V reverse should be no problem for any kind of LED. But it is seen as a kind of bad design to rely on the diode function of a LED. The reverse breakdown voltage may be lower than 40V and there may be a leak current at even lower voltages. 

5V should be no problem, if you want to go higher, put a normal diode in series with the LED (and don't forget the series resistor).

Btw. it doesn't matter if the resistor is on the anode or cathode side of the LED. The current in a serial circuit is the same everywhere. (see 'Kirchhoff's laws')