Regulator constant voltage reference generator - has multivibrator times control circuit operating with transistor for switching current to Zener diode and charging capacitor

摘要

The constant current generator is used for producing reference voltage for voltage regulator in battery powered measuring instrument. Constant current passes through zener diode to provide the reference voltage. The reference voltage circuit (REF) comprises current source (CC) supplied from unregulated input voltage (Ve) which is connected to a zener diode (D1) via a transistor (Tc) collector emitter circuit. A multivibrator timed control circuit (IT) operating in conjunction with transistor provides switching of current to zener diode and also provides charging current for a capacitor (CM) to attain avalanche voltage of the diode. This voltage is compared (COP) with fraction of regulated voltage (Vs) and error signal controls series regulator (REG) providing regulated voltage.