A 5-bits precision CMOS bandgap reference with on-chip bi-directional resistance trimming

This paper presents the design and implementation of a high precision CMOS bandgap voltage reference. It uses an on-chip 5-bits bi-directional trimming array with 32 voltage levels to achieve process variations and temperature independence. The digitally programmable array is binary weighted for accuracy and flexibility. Implemented in a 0.5 mum 2P3M CMOS process, it consumes a total power of 7.2 mW and takes an active area of 0.024 mm
²
. Through trimming, the voltage temperature dependence was reduced from 102 ppm/degC to 6.2 ppm/degC within the temperature range of 10degC to 50degC.