Bandgap current reference using widlar current source

Abstract

This paper has proposed a temperature insensitive current reference (CR) using Widlar current source. This CR has overwhelmed the direct relation of current to temperature present in Widlar current source. To obtain temperature insensitivity the proposed CR has been combined the complementary temperature behavior of current across MOSFET and BJT. Eldospice has supported the simulations of the proposed circuit using level 53, 0.18 µm CMOS technology with the help of EldoSpice. The proposed circuit has presented almost constant reference current of 63µA at a supply voltage of 1.8V for a temperature range of -30 to 100 °C. The proposed circuit has shown the maximum variation of 0.1µA as compared to 24.87µA in conventional Widlar current source.