vulture2600:
Hello,
Just wondering if I could use two LM7805's in parallel to double the output current or would it be better to split the outputs to separate loads.
No, never try directly paralleling voltage sources, you can destroy everything powered from them if it
goes into oscillation, and they will not current share evenly even anyway - get a proper power source for
the load.
The only exception is where you have identical battery cells, or power supplies specifically designed
for paralleling, and read the manual if you have such...
Related question: Is the heat dissipated dependent on current draw AND voltage reduced or just voltage reduced?
power is Vin * Iin - Vout * Iout
Normally Iin is very very close to Iout, so (Vin-Vout) * Iout is a good approx.