Area-Efficient Switched Capacitor Non-Filtering Circuits: Sum-Gain Amplifiers.

摘要

Switched capacitor sum-gain amplifiers (SGAs) are widely used in parallel fIlter systems. The capacitance spread of such circuits is proportional to the coefficient spread, thus making conventional SGAs un- suitable for high gain applications. SGANs with different input phases and a SGA with the same input phase are discussed, and a new area-efficient SGA, which can reduce the capacitance spread to the square root of coefficient spread ratio, is proposed. Furthermore, the non-ideal effects of op-amp like fInite DC gain and offset voltage are compensated by using the offset storing capacitor. All the circuits designed here only use the bi-phase clocking scheme.