CMOS Current Amplifiers Exhibiting Independent AC and DC Current Amplification

摘要

A CMOS circuit topology is demonstrated for the amplification of high-frequency AC currents without requiring similar DC current amplification. This technique is useful for current-domain amplification and processing of signals when low DC power consumption is necessary. Large amounts of AC gain can be achieved using this technique without requiring equivalent DC current gain, which would increase power consumption. Two amplifiers designed using this concept are discussed, one based on a standard current mirror architecture and the second using a cascode-type configuration. Measured results and analysis show the efficacy of this technique for the amplification of multi-Gb/s current-domain signals when implemented in a 0.12μm CMOS technology. Single-stage AC current gains of 12dB are achieved with unity DC current gain, while operating from supply voltages less than 1.0V. Temperature stable gain is also achieved.