A Test Fabrication and Measurement Results of Low Voltage CMOS Current Mode Reference Circuit Based on Subthreshold Operation

This paper presents the measurement results of the low voltage CMOS current mode reference circuit which is designed using subthreshold operation of MOSFETs. This circuit ensures adjustment the temperature coefficient and the output voltage after fabrication by the trimming function. The proposed reference circuit has been designed and fabricated using 1-poly 2-metal 0.6 μm standard CMOS process. The silicon characteristics have been measured for the supply voltage range of 0 V to 3.6 V and the temperature range of -20 °C to 100 °C. The silicon measurement results of eight samples show the average output voltage of 0.54 V and the variation of 2.1 % before trimming compared with the typical design simulation of 0.50 V. And the supply voltage range is from 1.1 V to 3.6 V in spite of using 0.6 μm standard CMOS process. Although the output voltage and the temperature coefficient of the silicon results show the discrepancy from the simulation result, we could demonstrate that the output voltage can be adjusted to the target characteristic by trimming function.