I've been designing a voltage comparator to check battery voltage using LEDs.
This is the schematic:
The circuit works fine when powering it with 4V, but won't pull the output high (turn the LEDs off) when powering it with 3V.
Any suggestions or things I missed?
Thanks in advance!
The TS391 has a n open collector output so it can never drive the drive the output high. You provide a pull-up to bring the output high.
If I understand your circuit, one TS391 input is at 2V but what is the voltage on the other input when the circuit doesn't work?
I shoud've noticed that, weird that is does work at 4V though.
When I measure the zener voltage is ~2.18V (inverting input) and the non-inverting input is 3.4V.
I shoud've noticed that, weird that is does work at 4V though.
When I measure the zener voltage is ~2.18V (inverting input) and the non-inverting input is 3.4V.