Compact power-efficient CMOS exponential voltage-to-voltage converter

In this paper, a novel low-voltage low-power implementation of an exponential voltage-to-voltage converter (EVVC) is presented. It is based on a pseudo-exponential approximation whose terms are easily achieved by the nonlinear currents of a class-AB transconductor. The circuit is able to operate correctly for supply voltages as low as V GS + 2V DSsat . Simulation results in a 0.5mum CMOS technology show a 47 dB output voltage range with linearity error less than plusmn0.5dB at plusmn1.5 V supply voltage. The power dissipation is less than 100muW