摘要 |
An operational amplifier driver capable of canceling an offset voltage of an operational amplifier includes the operational amplifier, first to third switches and a capacitor. The operational amplifier has a chopper, first and second input terminals and an output terminal. The first switch receives an input voltage and is connected to the first input terminal. The second switch is connected to the first input terminal and the output terminal. The third switch is connected the second input terminal and the output terminal. The capacitor is connected to the second input terminal. Because the operational amplifier driver directly charges/discharges the capacitor through the output terminal, and the polarities of the first input terminal and the second input terminal may be changed, the operational amplifier driver can shorten a charge/discharge time of the capacitor and cancel the offset voltage without increasing a level of an input signal.
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