I am putting some LEDS in my car, I have ran into a problem throughout the car. The voltage when the car is off is 11.3 volts and when the car is running the voltage is anywhere from 13.5-14.5 volts. Now, unless there's a way i don't know of, this is difficult to work with when you are trying to wire up some leds for the dash and you want them to be as bright as possible and not fluxuate at all when you turn on the car or boost the rpms. With all that said, I am looking at building this circuit. I do know the LM317 is capable of providing 1.5A but needs a heatsink when it's at 500mA or more. I want to wire up 8 series of LEDS (4 in each series) 20mA for each LED at a Voltage drop of 2v for each LED also. They are red ones. I want to set the circuit to output 10v. I do not know how to calculate the current that I am demanding from the LM317 so that I do not exceed the amount it can supply. Can someone help me on this.
I have one more question. If I have a 5 leds in a series and each has a voltage rating of 2v and the supply voltage is 10V do I need a resistor for this? Thanks
http://www.circuitsonline.net/circuits/view/97
Here is the link to the circuit I'm wanna build. If anyone has any better ways of accomplishing this please feel free to speak up. Thanks.
I have one more question. If I have a 5 leds in a series and each has a voltage rating of 2v and the supply voltage is 10V do I need a resistor for this? Thanks
http://www.circuitsonline.net/circuits/view/97
Here is the link to the circuit I'm wanna build. If anyone has any better ways of accomplishing this please feel free to speak up. Thanks.
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