Design and optimisation of a GaAs switched capacitor filter

Consideration is given to a GaAs second-order switched-capacitor bandpass filter. The design incorporates a new switched driver circuit and a new buffer for driving off-chip loads. The geometries of the high-gain, single-stage cascode operational amplifiers are scaled in relation to the particular capacitive loads they experience. Also, the switched capacitor circuit is modified to ensure that amplifier loading is suitable in all switch phases. The circuit has been submitted for fabrication and is expected to achieve a midband frequency of 20 MHz using a switching frequency of 500 MHz.<<ETX>>