For a battery powered application, what is the most energy efficient way to invert a signal that is high (~+5v) most of the time? I can make a NOT gate with a mosfet and some big resistors, but it seems that would just be continuously dumping power. Is there a better way?
The use case is a circuit that will sleep 99% of the time (1-2 minute sleep time), waking occasionally to do some work (0.5 to 1 second work time) then go back to sleep. To sleep the circuit we're actually turning off the voltage regulator, then using the trigger from a coin cell powered real time clock to enable the voltage regulator during work times. The problem is the RTC output is normally high and pulls low when the clock expires, while the voltage regulator requires a logic low to be off and a logic high to be turned on. So I need to invert the signal from the RTC, but in a way that doesn't kill my battery.
Edit: What if I used a pair of logic level mosfets, one n-channel and one p-channel?
The use case is a circuit that will sleep 99% of the time (1-2 minute sleep time), waking occasionally to do some work (0.5 to 1 second work time) then go back to sleep. To sleep the circuit we're actually turning off the voltage regulator, then using the trigger from a coin cell powered real time clock to enable the voltage regulator during work times. The problem is the RTC output is normally high and pulls low when the clock expires, while the voltage regulator requires a logic low to be off and a logic high to be turned on. So I need to invert the signal from the RTC, but in a way that doesn't kill my battery.
Edit: What if I used a pair of logic level mosfets, one n-channel and one p-channel?
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