Integrator and analog-to-digital converter

An integrator, comprising:

• an operational amplifier, wherein the operational amplifier comprises a first input terminal, a second input terminal, a first output terminal and a second output terminal;
• a first offset capacitor and a second offset capacitor, wherein the first offset capacitor is coupled to the first input terminal, and the second offset capacitor is coupled to the second input terminal;
• a plurality of controllable switches, a plurality of input capacitors and a plurality of integral capacitors, wherein the input capacitors and the integral capacitors are connected to the operational amplifier via the controllable switches, to control an operation mode of the integrator,
• wherein the controllable switches are configured to control operation states of the first offset capacitor and the second offset capacitor in a first phase and a second phase of an operation cycle to eliminate an offset voltage of the operational amplifier;
• and wherein:
• the first offset capacitor and the second offset capacitor are configured to store the offset voltage in the first phase;
• and
• the offset voltage of the operational amplifier is eliminated by counteracting the offset voltage with a voltage across the first offset capacitor and a voltage across the second offset capacitor in the second phase.