low battery indicator

I made a low battery cutoff circuit to monitor my 12v lead acid battery using TL431. I followed the circuit diagram shown below. Sorry for the hand-drawn schematic. I am however not satisfied with the outcome, since I understood with my little knowledge of TL431 that it would work better than a...

I'm working on a handheld project that runs off a single cell 3.7V Li-ion cell. I would like to trigger an LED to turn on when its voltage drops down to 3.3V. I have seen other answers with a TL431 IC that uses the a voltage divider to set the threshold (if I'm understanding the circuit...

hello, I was reading in multiple papers that some researchers will use a weak power supply to power electronics that are at higher power demand. They do that by using a capacitor and some circuits to store energy and releasing it at once when it is enough. I believe the circuit will maintain...

Hey guys, already got lot of informations out of this forums. THANK YOU FOR THAT. I´m working on little project but can´t best solution. In general I need a simple 12V low batterie alarm (with a low current, cut voltage by potentiometer, 1/60Hz Alarm Tone). I created a circuit with a LM358...

Hi! I would be very grateful if you can help me. I have been building some circuits to turn on a LED when the battery is low (images), but there is a problem: The led dim and blink between the OFF and fully ON state for some minutes. My circuit consumes 0.23A and is supplied by a 3.7v/1400mAh...