Design of a trimmed current reference with a low temperature drift

作者：Tang Hualian^*; Zhuang Yiqi; Zhang Li; Jing Xin; Du Yongqian

来源：Journal of Xidian University, 2013, 40(4): 130-136.

DOI：10.3969/j.issn.1001-2400.2013.04.022

• Bandgap Reference
• Compensated circuits
• Component tolerances
• Current reference
• Low temperature drifts
• Process Variation
• Temperature coefficient
• Temperature drifts

Component tolerances and mismatches due to process variations severely degrade the performance of bandgap reference circuits. Based on device mismatch models, a current reference Iref with adjustable output current from 15 μA to 80 μA is designed. A compensated circuit is used to reduce the temperature drift. To achieve more accurate current reference, an 8bit bi-directional trimming array with 127 current levels is proposed. This digitally programmable array is binary weighted for accuracy and flexibility. Simulation shows that the temperature coefficient is 26 ppm/°C over the wide range of -40°C to 120°C when the output current is 15 μA. Based on the CMOS 0.13 μm technology, the measurement results show that the trimmed range and precision for current reference are -14.3%&middotIref-14.3%&middotIref and 0.11%&middotIref, respectively. The circuit could be applied to high precision A/D and D/A converters.

• 出版日期2013
• 单位西安电子科技大学