| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor integrated circuit for a communication (high-frequency LSI) having an amplifier circuit which can complete an offset cancelling operation in a predetermined time, even when an amplifier having a fixed gain and a high-order low-pass filter are provided at the final state to amplify a reception signal in association with an amplitude modulation like an EDGE method. SOLUTION: The semiconductor integrated circuit for the communication comprises a plurality of gain variable amplifiers (PGA1 to PGA3) for amplifying the reception signals, and a plurality of filter circuits (LPF1 to LPF3) connected in multi-stages. In the filter circuits, the final stage has a final amplifier (FFGA) set at its gain irrespective of the level of the reception signal and a higher-order filter circuit (LPF) having higher order than other filter circuits (LPF1 to LPF3) and the amplification factor is variably set in response to the level of the reception signal, and a plurality of offset correcting circuits (OFC1 to OFC4) are provided for correcting the DC offsets corresponding to the plurality of the gain variable amplifiers and the final amplifier.
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