| 摘要 |
PROBLEM TO BE SOLVED: To accelerate offset control in an analog/digital converting circuit while simplifying the circuit by complementarily regulating the current between both differential circuits so as to decrease the offset corresponding to a voltage comparison output. SOLUTION: When an output signal VM is at a low level and/VM is in a high level, the voltage drop of a load resistor R2 is small including the offset of the entire circuit. Therefore, concerning the capacitors C2 and C1 for control voltage holding provided at the gates of differential MOSFET M2 and M1, the capacitor C2 is charged and the capacitor C1 is discharged respectively by current sources 13 and 12 so as to increase the current of the resistor R2 and to decrease the current of a resistor R1 and when the signal VM is changed into low level and/VM is changed into high level, operation for charging the capacitor C1 and discharging the capacitor C2 is mutually repeated so as to increase the current of the resistor R1 oppositely. Then, offset is turned into state close to zero.
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