| 摘要 |
An integrated compression amplifier that can be constructed in CMOS technology and whose threshold voltages are programmable. The compression amplifiers can be built into a multi-channel AGC device, so that the circuit can be co-integrated on a "switched capacitor" filter chip in CMOS technology. The compression amplifier circuit essentially involve a feedback amplifier whose gain is controlled by the output amplitude. To this end, an amplifier SC having variable gain constructed as a "switched capacitor" amplifier, a rectifier unit GR' as well as a low-pass filtr TP' are in a feedback branch and a two quadrant multiplier ZM1 is connected between the input and output Ue', Ua' of the compression amplifier. The output of the lo-pass filter TP' is thereby fed back onto the control input of the two quadrant multiplier ZM'.
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