摘要 |
A high-swing current mirror includes a cascode current source and a current source bias circuit. The current source includes first and second bias terminals and an output terminal. The bias circuit includes transistors M1, M2A, M2B and M3A. Transistor M1 has a gate, source, and drain, with the gate coupled to the drain. Transistor M2A has a gate, source, and drain, with the gate and source of transistor M2A coupled to the gate and source, respectively, of transistor M1. Transistor M2B has a gate and drain coupled to one another and to the second bias terminal and a source coupled to the drain of transistor M2A. Transistor M3A has a gate and drain coupled together and to the first bias terminal and a source coupled to the sources of transistors M1 and M2A. The transistors in the cascode current source and current source bias circuit have ratios of device transconductance parameters such that the cascode current source remains in saturation to provide the highest possible voltage swing at the output terminal.
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