| 摘要 |
An operational amplifier arrangement includes besides the two-stage operational amplifier, a third stage for tracking and holding the input offset of the first stage during an offset compensation phase which regularly interrupts the normal operation of the arrangement. To this purpose four switches are clocked, whereby the first stage is decoupled from the second stage during an offset compensation phase, whereby the feedback loop of the third stage is interrupted during normal mode, and whereby during the offset compensation phase the input is decoupled from the arrangement, while both input terminals are shorted. A Miller capacitor across the second stage prevents the output from drifting during the offset compensation mode.
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