Correlated double-sampling circuit capable of cancelling offset

The invention relates to a correlated double-sampling circuit capable of cancelling offset, belonging to the field of design of high-precision and high-quality signal acquiring and image obtaining circuits. The correlated double-sampling circuit comprises an operational amplifier, a feedback capacitor, two line conduction switches, three sampling capacitors, four sampling switches, a fixed potential holding capacitor and two state conversion switches; all the switches are controlled by clock signals; and the clock signals work in the two previous and later non-overlapped stages of the four sets of control switches. According to the correlated double-sampling circuit disclosed by the invention, offset cancellation of the operational amplifier can be realized by adjusting the proportion of the capacitors; the correlated double-sampling circuit is nothing to do with gain of the operational amplifier; therefore, the design difficulty of the operational amplifier is reduced; low-gain offset cancellation of the operational amplifier can be realized; furthermore, the circuit structure is simple; the time sequence controller manner is simple; and influence of offset voltage on sampling output can be effectively reduced.