A Low Power Low Supply MOS-Only Subthreshold Voltage Reference for Wide Temperature Range

• Main Authors: Pratosh Kumar Pal, Rajendra Kumar Nagaria
• Format: Article
• Language: English
• Published: VSB-Technical University of Ostrava 2019-01-01
• Series: Advances in Electrical and Electronic Engineering
• Subjects: current mirror; low-power; low-voltage; sub-1v circuit; subthreshold mos.
• Online Access: http://advances.utc.sk/index.php/AEEE/article/view/3197
• ISSN: 1336-1376; 1804-3119

A Sub-1V, MOS-only Voltage Reference Circuit (VRC) has been proposed with the utmost of transistors working as subthreshold region for low-supply and low-power applications. A supply-insensitive current is passed to Active Load Circuit (ALC) for supply and temperature independence at the output reference voltage. It has four current mirrors connected in a closed loop configuration to generate a supply-independent current which is passed through the ALC resulting supply and temperature insensitive output reference voltage. The ALC has a combination of two subthreshold NMOS transistors having different threshold voltages. The presented VRC is simulated using standard 90 nm CMOS model for 0.25-1 V supply voltage range. The simulation result gives minimum operating voltage required as 0.25 V for which all transistors work in their respective region of operation. For the supply range of 0.25-1 V, the obtained mean voltage reference is 100.4 mV with the line regulation of 0.186 mV/V. The temperature coefficient (TC) of 51ppm/°C is achieved for a wide temperature range of -50 to 135°C with the given minimal operating supply voltage. The power dissipation for minimal supply voltage at room temperature is 33 nW. The proposed VRC exhibits a high PSRR of -52.5 dB at 100Hz and -29 dB at 1 MHz.