Input common-mode compensation circuit and method and pipelined analog-to-digital converter

A pipelined analog-to-digital converter, comprising:

• an input common-mode compensation circuit, wherein
• the input common-mode compensation circuit includes:
• an energy storage module, wherein a first end of the energy storage module is connected to an input end of a residual amplifier;
• a switching selection module, wherein an input end of the switching selection module is connected to a second end of the energy storage module, and a first output end of the switching selection module is grounded;
• and
• a feedback compensation module, wherein a first input end of the feedback compensation module is connected to the first end of the energy storage module, a second input end of the feedback compensation module is connected to a reset voltage of the residual amplifier, and an output end of the feedback compensation module is connected to a second output end of the switching selection module,
• wherein
• during a reset stage of the residual amplifier, the input end of the switching selection module is connected to the first output end of the switching selection module, and the energy storage module is charged under the action of the reset voltage, and
• during a working stage of the residual amplifier, the input end of the switching selection module is connected to the second output end of the switching selection module, and feedback compensation is applied to the energy storage module by the feedback compensation module, thereby compensating and adjusting a common-mode value of an input signal of the residual amplifier;
• the input common-mode compensation circuit is connected to the input end of the residual amplifier in the pipelined analog-to-digital converter, and
• the input common-mode compensation circuit compensates and adjusts a common-mode value of the input signal of the residual amplifier.

An input common-mode compensation method for compensating and adjusting a common-mode value of an input signal of a residual amplifier in a pipelined analog-to-digital converter, comprising:

• providing an input common-mode compensation circuit including:
• an energy storage module, wherein a first end of the energy storage module is connected to an input end of a residual amplifier;
• a switching selection module, wherein an input end of the switching selection module is connected to a second end of the energy storage module, and a first output end of the switching selection module is grounded;
• and
• a feedback compensation module, wherein a first input end of the feedback compensation module is connected to the first end of the energy storage module, a second input end of the feedback compensation module is connected to a reset voltage of the residual amplifier, and an output end of the feedback compensation module is connected to a second output end of the switching selection module,
• wherein
• during a reset stage of the residual amplifier, the input end of the switching selection module is connected to the first output end of the switching selection module, and the energy storage module is charged under the action of the reset voltage, and
• during a working stage of the residual amplifier, the input end of the switching selection module is connected to the second output end of the switching selection module, and feedback compensation is applied to the energy storage module by the feedback compensation module, thereby compensating and adjusting a common-mode value of an input signal of the residual amplifier,
• during the reset stage of the residual amplifier, using the reset voltage at the input end of the residual amplifier to charge the energy storage module;
• and
• during the working stage of the residual amplifier, using a feedback compensation module to perform feedback compensation on the energy storage module, thereby compensating and adjusting the common-mode value of the input signal of the residual amplifier.