25 A RMS SCR for phase-control and AC switching
The STMicroelectronics TYN225RG is a standard-recovery SCR in a TO-220-3 through-hole package, rated for 200 V off-state and 25 A RMS on-state current (16 A average). It handles non-repetitive surge currents of 250 A at 50 Hz and 260 A at 60 Hz, giving headroom for motor-start and capacitor-charging transients.
Gate drive and conduction losses
Maximum gate trigger current is 40 mA at 1.5 V — a standard logic-level driver or a simple resistor from a 5 V supply will fire it. Once latched, the holding current of 50 mA minimum keeps the SCR conducting; below that threshold the device turns off. On-state voltage drop is 1.6 V max at rated current, so at 16 A average the conduction loss is about 26 W — the TO-220 tab needs a heatsink sized for that dissipation in your airflow.
Off-state leakage and blocking performance
Maximum off-state leakage is 5 µA at rated 200 V — negligible for most designs, but worth noting if the load is a high-impedance circuit where microamps matter. The standard recovery type means turn-off time is not optimised for high-frequency switching; this part is for line-frequency (50/60 Hz) phase control, not for PWM or fast commutation.