Voltage monitoring circuit for monitoring connection of battery to electronic equipment contg. microcontroller supplied from voltage supply via buffer capacitor

摘要

The circuit has a coil connecting the buffer capacitor to the voltage supply (1). A narrow voltage pulse is periodically fed from a microcontroller (7) output (8) to the common circuit point (P) of the voltage source (1) and coil (2). The pulse is essentially short circuited if the battery is connected properly. The common circuit point is also connected to an input (9) of the microcontroller which signals the absence of the battery if the narrow pulse is received.