800 V / 10 A SCR in a TO-220 — what it handles
The STMicroelectronics TYN810RG is a standard-recovery SCR rated for 800 V off-state and 10 A RMS on-state current, housed in a through-hole TO-220-3 package. It is designed for line-voltage phase-control applications such as motor speed controllers, industrial power supplies, and AC heater regulation where the 800 V blocking voltage provides margin on 230 VAC mains (peak ~325 V) and covers 400 VAC line-to-line in three-phase systems. The 10 A RMS continuous rating in a TO-220 means the case-to-ambient thermal path is the limiting factor — a heatsink is expected for sustained loads above a few amperes. The 100 A / 105 A non-repetitive surge current (50/60 Hz) covers inrush from capacitive loads or motor start.
Gate drive and trigger levels
Maximum gate trigger current is 15 mA, with a maximum gate trigger voltage of 1.5 V. This is a standard-sensitivity SCR — compatible with optocoupler or pulse-transformer gate drives from a 5 V logic rail or a dedicated gate-drive IC. The 30 mA maximum holding current means the SCR latches reliably once triggered; below that threshold the device turns off when the load current drops near zero.