The complementary Darlington-a novel current source for ICs

Compared with the performance of a single transistor operating in the common-base configuration, the complementary Darlington can be considered as a three-terminal device whose current gain and output resistance are both increased by a factor equal to the β of the complementary transistor, and whose partition noise is dominated by the base current of the latter. The circuit operation is based on positive feedback, but stability is unconditional since the loop transmission LT≪1