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Voltage Regulator

IP.com Disclosure Number: IPCOM000075341D
Original Publication Date: 1971-Sep-01
Included in the Prior Art Database: 2005-Feb-24
Document File: 2 page(s) / 21K

Publishing Venue

IBM

Related People

Hansen, AA: AUTHOR

Abstract

This is a voltage regulating circuit providing a fixed and well defined voltage at VBB. Voltage regulation is achieved by feedback through a "DOUBLE" Darlington coupling. The voltage VBB is defined by the ratio of R2/R1 with respect to voltage available (VCC, VEE). R3 determines the current level to operate in. The feedback are generated by T2 and T3 for push-pull, respectively. If VBB goes positive with respect to its defined voltage, T1 tends to turn "ON" harder, tending to turn T2 "OFF" and further tending to turn T3 "ON". The emitter current of T2 becomes limited and the collector current of T3 increases, pulling VBB negative to the desired voltage. In the alternative, if VBB goes negative with respect to the desired voltage, then T1 tends to turn "OFF" limiting the collector current of T3.

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Voltage Regulator

This is a voltage regulating circuit providing a fixed and well defined voltage at VBB. Voltage regulation is achieved by feedback through a "DOUBLE" Darlington coupling. The voltage VBB is defined by the ratio of R2/R1 with respect to voltage available (VCC, VEE). R3 determines the current level to operate in. The feedback are generated by T2 and T3 for push-pull, respectively. If VBB goes positive with respect to its defined voltage, T1 tends to turn "ON" harder, tending to turn T2 "OFF" and further tending to turn T3 "ON".

The emitter current of T2 becomes limited and the collector current of T3 increases, pulling VBB negative to the desired voltage. In the alternative, if VBB goes negative with respect to the desired voltage, then T1 tends to turn "OFF" limiting the collector current of T3. By limiting the collector current of T1, node B tends to rise toward VCC turning T2 "ON" harder. The increase in the emitter current of T2 tends to drive VBB positive to the desired voltage.

The voltage drop across T1 is defined as two diode drops preventing it from going into saturation.

Since the voltage regulator consists only of transistors of one conductivity type and resistors, it is ideally suited for manufacture in the form of a monolithic integrated circuit.

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