公开(公告)号：US10677664B1

公开(公告)日：2020-06-09

申请号：US16416390

申请日：2019-05-20

申请人： Hong Kong Applied Science and Technology Research Institute Company, Limited

发明人： Chun Fai Wong ,  Tai Yin Wong ,  Guangjie Cai

IPC分类号： G01K15/00

摘要： A single-temperature-point temperature-sensitivity sensor assumes that all sensitivity lines converge at absolute zero temperature, so during calibration measurement is needed at only one temperature. A sensor output voltage is generated by current from a mirrored current source flowing through a variable resistor. During calibration, the resistance of the variable resistor and the mirror ratio of the mirrored current source are adjusted. An error amplifier compares voltages generated by unit currents generated by unit current sources to adjust the unit current sources and the mirrored current source. Each unit current flows through a grounded-base PNP transistor. A switchable PNP transistor is in parallel with one of the grounded-base PNP transistors and has its base switched on and off to adjust the PNP current for two measurements. The difference between the two measurements is compared to a calibration target to adjust the variable resistor and mirror ratio during calibration at a single temperature.