In this letter, a linear variable resistor circuit using an FG-MOSFET (floating-gate MOSFET) is proposed. This is based on Schlarmann's variable resistor and is very simple. The advantage of the proposed circuit is a wide-input range. The utility of the proposed circuit was confirmed by HSPICE simulation with 1.2 µm CMOS process parameters. The simulation results are reported in this letter.

In this paper, a voltage-controlled linear variable resistor (VCLVR) using a floating-gate MOSFET (FG-MOSFET) is proposed. First, the grounded VCLVR realization is discussed. The proposed circuit consists of only an ordinary MOSFET and an FG-MOSFET. The advantages of the proposed VCLVR are low-power and wide-input range and also the power consumption of the proposed VCLVR is the same as an ordinary passive resistor. The performance of the proposed circuits are confirmed by HSPICE simulations with a standard 0.6 µm CMOS process parameters. Simulations of the proposed VCLVR demonstrate a resistance value of 40 kΩ to 338 kΩ and an input range of 4.34 V within THD of less than 1.1%. Next, we proposed a new floating node linear variable resistor using the proposed VCLVR. The performance of the circuit is also evaluated through HSPICE.