I have a 3.6 V battery that I want to regulate down to 3.3 V and 1.8 V rails. I have already asked about the configuration of the two rails here.
My question here however is whether I should use a linear regulator or switching regulator. I know that regulating from 3.6 V down to 3.3 V results in fairly high efficiency with a low dropout regulator (3.3 / 3.6 = 91.67 %), but going to 1.8 V results in half the power being wasted as heat (1.8 / 3.6 = 50%).
I want to compare this 50% loss in using a linear regulator vs. using a switching regulator. This involves considering whether or not the extra power needed to power the regulator itself is greater than the power conserved in using it.
How would I go about calculating this power lost vs. power conserved in order to compare it with the linear regulator?
I know that the power wasted in a linear regulator can be calculated simply by (Vout - Vin) * current drawn, but how do I calculate this for a switching regulator?
What kinds of switching regulators would be best for this application? (Buck regulator?)