12v step down module?

[alanw]

Originally Posted by Baja_Traveler

No.

Unless you go very high dollar, step down transformers use resistors to drop the voltage, wasting the excess energy as heat.

Actually step-up/down transformers don't generally use resistors, they just use coils and an iron core. Using resistors to achieve a voltage drop is a simple circuit that does indeed burn off excess energy as heat.