I want to drive a high output LED from a 14V LiPo battery and I just want to check that I've got the most efficient way to do this.
This is the LED , current is 700mA @ 2.9V
My battery will give me about 14.8V when fully charged
If I use only a current limiting resistor (18 ohm), I will be loosing about 9 watts across the resistor, ouch! But if I instead use this voltage regulator to get 3.3V, then I'll only need about .57 ohm resistance and I'll lose less than 1/2 watt to the resistors. However I see that this regulator can dissipate up to 12W, but I'm unsure how much power the regulator will dissipate under the load I'm proposing.
Will the regulator most likely run cool and be the most efficient way to go, or will I be better with a simple big hot resistor? Or maybe a PWM solution of some sort would be better?
This is the LED , current is 700mA @ 2.9V
My battery will give me about 14.8V when fully charged
If I use only a current limiting resistor (18 ohm), I will be loosing about 9 watts across the resistor, ouch! But if I instead use this voltage regulator to get 3.3V, then I'll only need about .57 ohm resistance and I'll lose less than 1/2 watt to the resistors. However I see that this regulator can dissipate up to 12W, but I'm unsure how much power the regulator will dissipate under the load I'm proposing.
Will the regulator most likely run cool and be the most efficient way to go, or will I be better with a simple big hot resistor? Or maybe a PWM solution of some sort would be better?