| 摘要 |
PROBLEM TO BE SOLVED: To obtain a parallel operation type A/D converter where a high speed operation and high precision can be realized. SOLUTION: An offset cancellation circuit 5 that detects an offset and generates a cancellation signal in response to the offset is provided independently to each voltage comparator circuit 4. The voltage comparator circuit 4 compares a signal voltage 4IN with a reference voltage 4REF and adds an inverted offset to the offset based on an offset cancellation signal 5OFC to cancel the offset of the input to the comparator circuit. A voltage division circuit 2 generates the reference voltage. Switch circuits SW1, SW2 apply a signal voltage to a reference voltage input terminal and a signal voltage input terminal of each voltage comparator circuit for an offset detection period and the voltage comparator circuit outputs a comparison result in response to the input offset. The offset cancellation circuit generates the offset cancellation signal on the basis of the comparison result.
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