GENERATING CIRCUIT FOR REFERENCE VOLTAGE

摘要

PURPOSE:To obtain a reference voltage generator which secures the reference voltage of a high level with the drive voltage of a low level, by using a current mirror circuit. CONSTITUTION:The input side of a diode D1 is connected to a Zener diode ZD together with the output side connected to a resistance R3 respectively. The emitter and the base of a transistor (TR) Q1 are connected to a resistance R4 and the output side of a diode D respectively. The resistance value is equal among both resistances R3 and R4. The inverse input terminal of an OP amplifier A is connected to a middle joint (b) between resistances R3 and R4 with the non-inverse input terminal connected to the earth and the output terminal of the amplifier A connected to the input side of the diode D1 respectively. Furthermore the collector of the TR Q1 is connected to a current mirror circuit C together with the power supply terminal set at the negative side of the amplifier A and the output side of the diode D. The voltage V is also impressed to the circuit C. Then the circuit C mirrors the current flowing to a voltage dividing part to control the current made flowing to the connection part of the diode ZD.