Sampling integrator for clocked active filter - has switched input capacitor and chain of switched capacitors connected to operational amplifier

摘要

The sampling integrator has a periodically switched capacitor (C1) connected via at least a second capacitor (C2, C2-Cn) to the inverting input (3) of an operational amplifier (1). The second capacitor is shunted by a switch. The switched capacitor (C1) has the same capacitance as the second capacitor. A third capacitor (5) connects the operation amplifier output to its inverting input and has a specified value related to the capacitance of the switched capacitor, to the integration constant and to the number of speed capacitors. The integrator can be readily realised as an integrated circuit.