Hello Friends,
The lm117 into constant current circuit (image attached for your review).
I have set the current using 3ohm resistor. using the formula I=1.25/R.
ie. 1.25/3 = 400mA. I made the circuit and tried this.
input = 3.7 V
operating voltage of led = 2.6~3V
When I connected the circuit and checked the current with the multimeter I got 200mA which suppose to be 400mA.
When I changed my input to 7.4V I used the test load before I am afraid the led burns, I got more than 1A current. why is the current changing to the change of voltage? I am attaching my circuit made by me.
The lm117 into constant current circuit (image attached for your review).
I have set the current using 3ohm resistor. using the formula I=1.25/R.
ie. 1.25/3 = 400mA. I made the circuit and tried this.
input = 3.7 V
operating voltage of led = 2.6~3V
When I connected the circuit and checked the current with the multimeter I got 200mA which suppose to be 400mA.
When I changed my input to 7.4V I used the test load before I am afraid the led burns, I got more than 1A current. why is the current changing to the change of voltage? I am attaching my circuit made by me.
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