A circuit for establishing the quiescent bias current of a differential amplifier with active collector loads (transistor loads). The collector current of an auxiliary transistor, held at the same base-emitter potential as the active loads, is applied to the input circuit of a current amplifier which supplies from its output circuit the combined emitter currents of the differential amplifier transistors. The base currents of the auxiliary transistor and of the active load transistors are decoupled from the input circuit of the current amplifier so that variations in such currents do not affect the quiescent biasing of the differential amplifier.