Discreet Latch Circuit

Schmitt triggers are preferable but it still works nonetheless. Use the buttons to “Set” and “Reset” the output. It is not a true SR latch. It is more useful instead as an adjustable hysteresis band for an OVLO circuit. For example, “ground” could be set to the threshold voltage desired to disable the output when an over voltage condition is present, and “hot” could be set at a much lower threshold voltage to re-enable the output after the over voltage condition has cleared, i.e., the OV state is “latched” in. In this scenario there would be no DC supply because the “inputs” would be tapped off and voltage divided down accordingly off of the mains input voltage.

published 4 years ago