Wideband BiCMOS operational amplifier - has reference voltage generator, differential amplifier, current source with cascode transistor and modified bipolar Wilson current mirror

摘要

The operational amplifier includes second and third npn-bipolar transistors (MP25,MP15) whose emitters are respectively connected to a reference potential generator (RSG) via emitter resistors (R21,R11). The bases of the second and third non-bipolar transistors are connected to the collector of the third npn-bipolar transistor (Q14). The second connection of a second p-channel MOS transistor is connected to the base of a first npn-bipolar transistor and to the second connection of a fourth p-channel MOS transistor. The gate of a sixth p-channel MOS transistor is supplied with a second reference voltage. ADVANTAGE - Has low number of transistors, saving chip area and minimising internal capacitance, increasing amplification characteristics, e.g. bandwidth, and reducing losses.