CMOS input level shifting circuit with temperature-compensating n-channel field effect transistor structure

摘要

A CMOS input level shifting circuit includes a temperature-compensating N-channel field effect transistor structure wherein a resistance in series with the source region includes an extension of a lightly doped P-type region in which the source and drain regions are diffused. This structure produces a temperature-compensating variation in the drain current proportional to the square of the series resistance without requiring modification of standard processes for manufacturing CMOS integrated circuits. The relatively large, temperature-dependent variation of the series resistance produces a corresponding temperature-dependent variation in the drain current that effectively temperature-compensates the switching point of the CMOS input level shifting circuit.