Building Simple LED circuit
Building Simple LED circuit
(OP)
Hello,
Im trying to design a LED lighting kit for a model car. I want to use the following LEDs in it:
4 White Super LEDs
Forward Voltage - 3.4 V Typical (max 4.0)
Forward Current - 30 mA
and 4 Super Red LEDs
Forward Voltage - 2.1 V Typical (max 2.5)
Forward Current - 50 mA
I will be running these of a dedicated NiCD battery pack. These LEDs will be continuously running when on. I would greatly appreciate any design help that anyone could offer me.
Thank you for your time and patience.
Im trying to design a LED lighting kit for a model car. I want to use the following LEDs in it:
4 White Super LEDs
Forward Voltage - 3.4 V Typical (max 4.0)
Forward Current - 30 mA
and 4 Super Red LEDs
Forward Voltage - 2.1 V Typical (max 2.5)
Forward Current - 50 mA
I will be running these of a dedicated NiCD battery pack. These LEDs will be continuously running when on. I would greatly appreciate any design help that anyone could offer me.
Thank you for your time and patience.





RE: Building Simple LED circuit
RE: Building Simple LED circuit
Thank you for your time and patience.
RE: Building Simple LED circuit
RE: Building Simple LED circuit
Connect all the LEDs of a color in parallel, connect red LEDs between common and the the junction between the 2nd and 3rd batteries, white cells between the common and +ve of the third. Perhaps a low value resistor for each branch to ease the voltage a bit.
Good luck,
Engin
RE: Building Simple LED circuit
The resistor value is R=V/I where V is the voltage across the resistor. V = (Vbatt - Vled) The resistor power is V x I where I is the current through the resistor. Choose a resistor with twice the power rating as the calculated power above. That will keep it cooler, and give the resistor some air to dissipate the heat.
RE: Building Simple LED circuit
Try Maxim, TI, etc. for LED driver chips, application notes and to request samples. This technology is rapidly growing right now.