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How to use LDR to be run with 12v DC motor? Answered

I want make a project that will run in light but as light turns off, circuit should be break

Im using :
1. 12V / 2Amp motor
2. LDR
3. 12 v supply
4. Laser light

Whenever light appends on LDR circuit should pass 12v for the motor and whenever light is brocken
circuit should have total resistance

so what Kind of components should i use or suggest me LDR based for above circuit


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4 years ago

R1 and P1 depend on the LDR...

D1 and D2 help make the NPN transistor really switch without going through a heating dissipation.

D3 is a reverse induction transistor protect diode.

The transistor is 10 amp because a motor draws more current starting up.

simple 12v motor.png

4 years ago

You need to use a transistor as a switch google ldr xswitch cct.