High input impedance differential amplifying circuit

Abstract

Abstract PURPOSE:To obtain high input impedance even at a single input stage composed of a bipolar transistor, by providing an input current compensating circuit suitable for an IC circuit. CONSTITUTION:Transistors (TR)Q1 and Q2 from a differential amplifier, and a TRQ6 is provided to equalize the current amplification factor of the TRQ1 to that of the TRQ2. A TRQ7 is a substrate PNP type for compensating a decrease in current amplification factor for a multi-collector lateral PNP TRQ8, and serves as a current mirror. A TRQ4 operates as a constat current absorption source and is driven by a bias power source V0. TRQ5 is arranged on an IC pattern closely to and in the same direction with the TRQ4 so as to improve the collector current I0 and tracking performance of the TRQ4.

Inventors

• 👤 Osamu Yoneda
• 👤 修 米田

Bibliographic Details