On Jan 16, 2013, at 12:43 PM, Richard <legalize at xmission.com> wrote:
"Joerg M. Sigle" <joerg.sigle at
jsigle.com> writes:
It may go to 170 mW per chip, ... but while
MOSTEK say their 4116 needs
up to 1 W max, I just see the TMS4116-20 more probably has 462 mW. So it
would save me... 19 W at best. Or less, because the unused power rails
cannot simple be turned off - or more, because the PSU is a rather
large, old, linear type.
Won't you get more savings by replacing the linear PSU with a switching PSU?
Depends on the relative efficiency of the linear vs. the switcher
at the given output voltage, and how much power is being run
through the power supply. Usually the answer is yes, but it can
also be the case that you're primarily concerned about the power
dissipated by the board itself because it can cause more heat
(and thus reliability) issues; obviously, whichever saves the
most power will also produce the least overall heat, but the
heat generated by the PSU is often vented out of the box a lot
more efficiently (not always).
- Dave