Features of JFET Computer Models in Microcurrent Mode on Exposure to Low Temperatures and Neutron Fluence

The current-voltage curves (CVCs) of silicon p-JFET and n-JFET, measured in the range of drain currents of about 60 dB, are considered. To describe the CVCs of the JFET in micromode, that is for the drain currents less than 1 μA, it is proposed to use the Shichman-Hodges model built into Spice-like programs with a set of parameters identified in the micromode. The modeling results and measurement data of the CVCs in the micromode is shown, as well as the simulation results at temperatures up to minus 197°C and on exposure to neutron fluence are presented. The adequacy of the p-JFET models is set accurate for the design of analog circuits. It was difficult to separate the linear area from the saturation area at the output CVC in a circuit with a common n-JFET source at drain currents less than 1 μA. To solve the problem with this CVC, we revealed the greatest discrepancy between measurements and modeling. Therefore, it is permissible to use the identified parameters of the n-JFET model only for evaluative modeling of microcircuits in the micro mode.