SOT-223 surface-mount triac for low-power AC switching
The BTA204W-600E,135 is a single triac in the SOT-223 package (TO-261-4, TO-261AA), rated 1 A RMS on-state current and 600 V off-state voltage — sized for low-current AC loads like solid-state relays, fan speed controllers, and small solenoid drivers on a surface-mount board. Its sensitive-gate logic-level trigger (10 mA max Igt, 1.5 V max Vgt) means a microcontroller GPIO or low-voltage logic output can fire it directly through a series resistor, without a separate driver transistor. Non-repetitive surge rating is 10 A at 50 Hz, 11 A at 60 Hz — enough to handle inrush from a small incandescent lamp or capacitive power supply on the first half-cycle.
Active production — no last-time-buy pressure
Maximum junction temperature is 125 °C, so the part can sit next to a warm heatsink or in a moderately ventilated enclosure without derating the 1 A RMS load.