Abstract This paper presents data collected from CMOS test circuits designed to characterize hot-carrier effects in digital switching circuits. Test circuits were configured as CMOS inverters, transmission gates, and NMOS transmission gates. The MOSFETs within the circuits could be probed so that the degradation of their dc characteristics could be directly measured. These circuits were hot-carrier-stressed under pulsed switching conditions similar to their operation in VLSI circuits. The results indicate that device degradation is strongly dependent on the circuit configuration and switching conditions. Transmission gate circuits exhibit a more severe degradation in switching characteristics than inverter circuits due to the localization of the hot-carrier-induced charge. The localized nature of hotcarrier-induced charge must be considered at the circuit simulation level to accurately assess the effect on circuit performance.