Analysis and Design of a Current Mirror Trans-conductance Switchable Op-amp for Switched-Capacitor Integrators

A switchable operational amplifier (op-amp) that uses a switched capacitor integrator has an advantage such as low power consumption and wide gain-bandwidth product. The power reduction is achieve by apply switching samples at the input and output capacitors. These capacitors can be otherwise would contribute in increase in power consumption. During the first phase of the sample the opamp completely turned off, at this instance the input capacitor is fully charged, which later can be used to drive the opamp. On the next second sample phase charged energy in input capacitor passes through the integrator capacitor, which turns on the opamp. On the second clock cycle of the first phase the output of opamp is fed to the output capacitor. Measurement of 1volt switchable opamp for switched capacitor integrator show 44 dB dynamic range in bandwidth of 30 KHz with 52dB peak SNR and the power consumption of 186 microwatt. Index Terms Circuits, operational amplifier (opamp), switchable opamp, switched capacitor (SC), switching. __________________________________________________*****_________________________________________________