Any less costly alternatives to the LT1157 3.3v high-side NFET switch driver you like? It's nice that it has two outputs but I only need one.
A hand-rolled charge pump-thing might work OK but probably challenging to get down to single-digit microampere standby current draw. I can live with 10s, though.
Dunno what p/n you meant. The LTC1981 is nice.
Den torsdag den 11. januar 2018 kl. 19.13.29 UTC+1 skrev bitrex:
what do you need to switch?
The client wants to build some custom sensors that transmit data over WiFi. They have a particular off-the-shelf 3.3 volt WiFi module they're enamored with and would prefer to use it without resorting to a full custom design, need it yesterday etc. but have been having a bear of a time messing around with some software API trying to send it the correct magic combination of commands to drop it into a low-power enough sleep mode to meet the requirements.
It's still drawing too much current; there's probably other stuff on the board consuming power that can't be affected via software. Suggestion: just take down its supply rail entirely when not in use. The actual sensing is fairly trivial and can be done by an 8-bit that one can be assured of a cookbook recipe to send into a very low-power sleep state.
use one of the numerous USB supply switches
here's a random google hit,
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