A 0.5 to 4 GHz true logarithmic amplifier utilizing monolithic GaAs MESFET technology

摘要

The design of the true logarithmic amplifier is reviewed, and the sensitivity of the circuit's performance to design or process errors is investigated. A GaAs monolithic dual-sign amplifier stage which has been developed for 0.5- to 4-GHz true logarithmic amplifier applications is described. This bandwidth is significantly greater than that of previously reported true logarithmic amplifier stages. A cascade of six of these stages has resulted in a logarithmic amplifier with a 70-dB dynamic range.