Adjustable Constant Current LASER Diode/LED driver

Adjustable Constant Current LASER Diode/LED driver


I was testing a couple of low-cost laser diodes that come from china and I was wondering why those diodes don’t have any protection/driver circuitry. Those diodes come with a simple series resistor for current control which is not a good idea nor stable. Laser diodes are harmful and should have some sort of constant current circuit as a basic protection for the laser diode. As a result, I built this circuit which provides highly accurate current control.  The module is a great tool to drive low-cost laser diodes with superb accuracy. This circuit can drive diode starting from 0 mA to 115mA, usually, these cheap diodes require around 30mA current. The project has an onboard multi-turn potentiometer to adjust the output current with great accuracy. It is advisable to turn the trim-pot to zero level and then hook-up the laser diode.

Adjustable Constant Current LASER Diode/LED driver – [Link]

Mike is the founder and editor of, an electronics engineering community/news and project sharing platform. He studied Electronics and Physics and enjoys everything that has moving electrons and fun. His interests lying on solar cells, microcontrollers and switchmode power supplies. Feel free to reach him for feedback, random tips or just to say hello :-)

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