Low noise high gain single chip NMOS AGC amplifiers for high speed lightwave systems.
01 January 1987
The design and test results of a single chip NMOS AGC amplifier are described. The amplifier has a maximum flat gain of 50 dB and a noise figure of 11 dB. The flat response from near DC to a 3 dB bandwidth close to 1 Ghz does not require tuning of any peaking circuits. The chip is also capable of operating at 3 GHz with unity gain delivering -8 dBm into a 50 ohm load. The amplifier operates with a supply voltage of 3 volts and is self biasing requiring no critical bias voltages. The global feedback scheme designed for this chip stabilizes it against large shifts in threshold voltage and ambient temperature variation of 170C.