Hi there,

I am building a little MP3-Player with the STM32F4Discovery. The Board is supplied by a LT1930 SEPIC Controller with 4AA NiMH. To prevend low voltage damage, i'd like to shutdown the LT1930 permanently after passing a specific voltage, measured by the ADC of the STM32F4. The LT1930 must then not be activated again until new batteries are supplied.

I have thought of a little FET Latch circuit (see attached).

My Questions are: Might that work in general? Are there more sophisticated solutions with fewer parts? I've searched a lot so far, but nothing suitable showed up.

The sleep mode of the uC is not an option, because other stuff is supplied after the LT1930 as well,

Thanks a lot beforehand for any directional advice!

 

Microchip make voltage monitors.
http://ww1.microchip.com/downloads/en/appnotes/00779a.pdf

They shutdown until supply exceeds threshold level. Available in 0.2 volt increments from 2 to 6 volts (different 3pin device for each).