DIFFERENTIAL AMPLIFIER CIRCUIT HAVING A DRIVER WITH SQUARE-LAW CHARACTERISTIC

摘要

The present invention provides a differential amplifier circuit having good mutual conductance linearity within a wider input voltage range and including a driver circuit for driving the first differential pair of transistors and the first differential pair by an output current. This output current is squared to compensate for the linearity of the mutual conductance of the differential pair. This driver circuit is a squarer or quadretail circuit. The signal to be amplified is applied to a pair of input terminals. An input terminal of the differential pair is connected to an input terminal pair to which a first input signal is to be applied. An input terminal of the driver circuit is connected to an input terminal pair to which a second input signal is to be applied. The amplitude of the first and second input signals is proportional to the signal to be amplified.