Notch filter for ripple reduction in chopper stabilized amplifiers

A chopper-stabilized amplifier comprising:

• (a) a first operational transconductance amplifier;
• (b) first chopper circuitry coupled to an input of the first operational transconductance amplifier for chopping an input signal and applying the chopped input signal to the input of the first operational transconductance amplifier, and second chopper circuitry coupled to an output of the first operational transconductance amplifier for chopping an output signal produced by the first operational transconductance amplifier;
• and
• (c) a switched capacitor notch filter having an input coupled to an output of the second chopper circuitry and performing an integrate and transfer function on a chopped output signal produced by the second chopper circuitry to filter a chopped output signal produced by the second chopper circuitry by operating synchronously with a chopping frequency of the second chopper circuitry to notch filter ripple voltages that otherwise would occur in the output of the second chopper circuitry.