A 155-MHz BiCMOS automatic gain control amplifier

This paper proposes a 155-MHz automatic gain control (AGC) amplifier implem ented in a double-poly-double-metal 1.0-mu m BiCMOS technology. The amplifi er contains an exponential-type variable-gain amplifier, a buffer-based fil ter, and asynchronous demodulation peak detector circuits. The initializati on and the output magnitude setup circuits are incorporated in the AGC ampl ifier. It yields an input dynamic range of at least 26 dB and provides a co nstant output of 1 V-pp at a 50-Omega load with AGC loop bandwidth of 80 kH z. The power consumption is 180 mW from a single 5-V supply.