| 摘要 |
PROBLEM TO BE SOLVED: To solve a problem of a differential amplifier which delivers differential signals of an outputs from first and second amplifiers receiving a signal to be amplified while operating in a third amplifier that the amplitude of an I/O signal of the second amplifier is limited by its power supply voltage if the offset voltage of an input signal is large, and thereby the range of the amplitude voltage of an input signal is limited substantially and the output signal is distorted. SOLUTION: The output voltage of a power supply section for supplying power to first and second amplifiers is shifted according to a reference voltage, and the reference voltage is substantially equalized to the offset voltage of an input signal. Since the power supply voltage of the first and second amplifiers is shifted according to the magnitude of the offset voltage, the range of an input signal can be widened. Furthermore, the generation of distortion is eliminated because a margin can be taken between the output signal level of the second amplifier and the power supply voltage. COPYRIGHT: (C)2009,JPO&INPIT
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