Abstract
Latchup cross-section measurements of HM6504, HM6641, HD6434, and HM6516, all CMOS devices were performed at various values of LET near threshold by adjusting the air pressure between the source and device. The energies of representative light and heavy fission fragments at the device were determined using an analytical approach which was considered preferable to spectrum measurements if the pulse-height defect in a silicon detector is unusually large.