A Novel CMOS Exponential Voltage Generator Based on Differential Pair's Transfer Characteristic

摘要

A novel voltage-mode CMOS exponential function circuit for VGAs is developed in this paper. The core circuit is based on a traditional differential pair and a newly-designed three-transistor differential pair. The generated exponential voltage starts from but does not cross the point of 0V. On a 0.25um CMOS process, the simulation results with 3.3V supply voltage show that the dB-linear function in the entire voltage control range achieves over 50dB range with an error less than 1dB.