RF upset susceptibilities of CMOS and low power Schottky 4-bit magnitude comparators

Integrated circuits for the military arena must be electronically robust. The authors describe measurements of RF upset levels on two 4-bit magnitude comparators, CD4585B and SN54LS85A, functionally identical and from different technologies, CMOS and low power Schottky. CW EMI (continuous-wave electromagnetic interference) from 1 to 200 MHz was coupled into each device type while test vectors were used to verify normal operation and subsequent upsets. The CMOS and the ALS devices showed decreasing RF susceptibility with increasing frequencies from 1 to 200 MHz. The differences in the susceptibility levels measured for the functional input ports are apparent. The CMOS devices´ roll-off is almost 20 dB/decade as compared to about 12 dB/decade for the ALS74 device