FGMTL based Low Voltage Current Mode Squarer/Divider Circuit

Abstract

A FGMTL (FGMOS Translinear) principle based current mode one quadrant squarer/divider circuit operating at low voltage in saturation region is presented. Squarer/divider is the key circuit which acts as a core building block for nonlinear signal processing functions. Low voltage square/divider can be constructed using FGMTL principle in place of MTL (MOS Translinear) principle in saturation. Multi-input nature of FGMOS transistor reduces the transistor’s threshold voltage which allows low voltage operation of the proposed circuit in saturation region. Proposed circuit is designed at a supply voltage of 0. 7V. It offers a bandwidth of 0. 5GHz when simulated in LTSPICE software using 0.18$\mu$m CMOS technology. THD of 2.3% to 4.7% is obtained for the sinusoidal peak to peak input current range from 1$\mu$A to 10$\mu$A at a frequency of 1KHz.