3 ms·
Nowadays you can pretty easily find switchers with sub-100nA quiescent current + leakage, e.g. TPS62840 (of course, that's assuming you're at room temperature..
by ejiblabahaba 3y ago
Nowadays you can pretty easily find switchers with sub-100nA quiescent current + leakage, e.g. TPS62840 (of course, that's assuming you're at room temperature... FETs at high temperature are all crap for leakage). I note you get 80% efficiency at 1uA out on this device with a 3.6V to 1.8V stepdown config; beats the LDO by a lot, particularly if you spend a lot of your time at uA load currents.
But spin-up time... Yeah that still sucks :)
- ilyt 3y agoAre there chips doing that but buck-boost ? I know there are for "normal" current range, but I haven't found anything super low power Use case: I want to just have a solar panel + supercap into microcontroller for IoT stuff so I want to suck that cap dry and avoid batteries for temperature range reasons.
- ejiblabahaba 3y agoMaybe TPS61094 or something similar? https://www.ti.com/lit/ds/symlink/tps61094.pdf https://www.ti.com/lit/ds/symlink/tps61094.pdf
- ilyt 3y agoOh, wow, it's even in stock, thanks. I was looking for something like that some time ago but back then only BQ25570 really fitted (and was overkill and a bit more pricy for that)
- FunkyDuckling 3y agoIssue with a lot of these and switching regulators is off chip inductors, which take up space. In small form factors, SOCs etc, you need to use charge pumps and LDOs for internal analog/mixed signal voltages.