A low-voltage CMOS voltage-controlled resistor with wide resistance dynamic range

Abstract

A 0.5 μm CMOS floating voltage-controlled resistor with wide resistance dynamic range and low supply voltage is presented. The current inputs of two second generation current conveyors are loaded by non-saturated MOSFET with controllable resistance. Both a quasi rail-to-rail operation and a wide resistance dynamic range, with large resistances, are achieved using the input signal adapters. For a single supply of 1.5 V and a range of input voltage from 0.2 V to 1.3 V, simulations show a linearity error smaller than 3.9 %, a resistance dynamic range of 250 (48 dB) with the largest resistance of 25.5 MΩ, and power consumption less than 0.1 mW.