The STMicroelectronics ACS108-8SN-TR is a logic-level sensitive-gate TRIAC from the ACS™/A.S.D® series, rated for 800 V off-state voltage and 800 mA RMS on-state current. It is a single-configuration device in a surface-mount SOT-223 package (TO-261-4). The sensitive gate (10 mA max trigger current, 1 V max trigger voltage) lets a microcontroller or logic output drive it directly, eliminating the driver transistor and its associated BOM cost. Typical applications include small appliance controls, solid-state relays for fan or pump switching, and lighting dimmers or flashers where the load is under 800 mA. The operating junction temperature range of -30°C to 125°C covers most indoor and outdoor commercial/industrial environments.
The 800 V off-state voltage (Vdrm) provides headroom for mains switching. The 800 mA RMS on-state current (It(RMS)) is the continuous load limit.
SOT-223 package — rework and board-fit notes
The SOT-223 (TO-261-4) is a surface-mount package with a large tab for thermal dissipation. The tab is electrically connected to the MT2 terminal.
There is no last-time-buy or obsolescence notice.