Voltage monitor for dry cell in electronic timepiece - has periodically activated comparator switching on LCD cell when voltage drops

摘要

The voltage monitor, for current sources, esp. dry cells, in electronic timepieces, has a liquid-crystal-display cell visible on the timepiece and switched by an appropriate circuit when the source's voltage drops below a given level. A reference voltage is compared with the source's voltage and the output of the comparator initiates the switching of the LCD cell. The comparator and its reference are switched in periodically at long time intervals; this is accomplished by a special timing circuit.