AMPLITUDE VARIABLE DRIVER CIRCUIT AND TESTING APPARATUS

摘要

An amplitude variable driver circuit for providing an output signal obtained by amplifying an input signal applied thereto, comprising a plurality of differential amplifiers connected in parallel with each other and receiving, at their respective base terminals, signals in accordance with the input signal; a resistor part connected in series with the plurality of differential amplifiers for generating the potential of the output signal in accordance with the total current flowing through the plurality of differential amplifiers; and an amplitude control transistor connected in series with the plurality of differential amplifiers for deciding the total amount of currents flowing through the plurality of differential amplifiers.