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How to build circuit for (2) small laser pointers switched from one transistor used as a switch.? Answered

I am building a device with two 5mW lasers 3.5 volt switched by a sensor and transistor switch. When both are in the circuit only one is on. what is the proper way to switch two lasers from one sensor/transistor?



7 years ago

That is because the lower forward voltage Laser LED predominates and
does no let the other get the voltage level to turn on.
Try putting a resistor ( 1 or 2 ohm ) in series with each Laser diode.


Either that, or just put them in series on a 7V supply.

Could you expand upon "When both are in the circuit only one is on"?
You want to switch between one and the other, using a "sensor" - what type of sensor?