| 摘要 |
PURPOSE:To improve the compensation characteristic of an offset without lowering stability or deteriorating a noise characteristic, by setting the fluctuation characteristic of the output of a pre-amplifier almost equal to the fluctuation characteristic generated at an offset detector. CONSTITUTION:The output signal of the pre-amplifier 2 is inputted to a first input terminal of a differential amplifier 4 via a fluctuation correction circuit 3. Also, the offset information of the output of the differential amplifier 4 is detected at the offset detector 5, is fed back to a second input terminal of the differential amplifier 4. And the fluctuation characteristic of the output of the pre-amplifier 2 is set almost equal to the fluctuation characteristic generated at the offset detector 5. |
