Ed_Gee wrote:
I would not expect an LM7809 to safely regulate a 10Watt load, if that's any help.
LM 78xx series is good up to 1.5A when properly heatsinked (although 1A is recommended).
Mexs 10W LED is going to draw about .750A or 750ma at 10V.
Also the regulator only needs to drop a few volts to get to the required 10V for this particular LED chip so it won't have to dissipate a lot of heat in the process.. which is well within the reach of a LM78xx regulator.
At 13V input the regulator needs to drop 3V at 750ma, that is about 2.25W of heat..
At 12V drop is 2V at 750ma for 1.5W of heat..
All well within the allowable specs for this chip..
