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STMicroelectronics ACS108-8TN-TR — Discrete Semiconductors

ST ACS108-8TN-TR TRIAC, 800V, 800mA, SOT-223

MPNACS108-8TN-TR
End of Life

STMicroelectronics ACS108-8TN-TR, ACS™/A.S.D® series, Logic-Level Sensitive-Gate TRIAC, Single, 800 V Off-State, 800 mA RMS On-State, Surface Mount SOT-223, -40°C to 125°C.

$0.57Ref. price · indicative, final on quote
STMicroelectronics ACS108-8TN-TR datasheet (PDF)
PackagingTO-261-4, TO-261AA
RoHSROHS3 Compliant
SeriesACS™/A.S.D®
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

ACS108-8TN-TR specifications
ParameterValue
SeriesACS™/A.S.D®
Triac typeLogic - Sensitive Gate
MountingSurface Mount
Voltage - off state800 V
Voltage - gate trigger (Vgt)1 V
Current - hold (Ih)10 mA
Current - gate trigger (Igt)5 mA
Current - on state (It (RMS))800 mA
Current - non rep. surge 50, 60Hz13A, 13.7A
Operating temperature-40°C ~ 125°C (TJ)
PackageTape & Reel (TR); Cut Tape (CT)
ConfigurationSingle
CaseTO-261-4, TO-261AA

Product details

What this 800 V, 800 mA sensitive-gate TRIAC is for

The STMicroelectronics ACS108-8TN-TR is a logic-level sensitive-gate TRIAC from the ACS™/A.S.D® series, designed for AC load switching where a microcontroller or logic output directly fires the gate. Its 800 V off-state voltage and 800 mA RMS on-state current suit it for low-power mains-voltage applications: small fans, solenoid valves, incandescent lamp dimmers, and resistive heating elements in appliances or industrial controls.

SOT-223 package — board space vs thermal management

The SOT-223 surface-mount package (TO-261-4 variant) is a compact three-lead power package with a large tab for heat sinking.

For a production BOM, this part can be qualified without planning for a forced redesign cycle. The ACS™/A.S.D® series has been a stable ST product line for years, and the active status suggests continued manufacturing support.

Frequently asked questions

What is the closest second-source or equivalent for ACS108-8TN-TR?

The ACS108-8SN-TR is a near-identical sibling from the same ACS™/A.S.D® series — same 800 V off-state, same 800 mA RMS, same SOT-223 package, same sensitive gate. The difference is the temperature range: the -8SN is rated -30°C to 125°C, while the -8TN covers -40°C to 125°C. For indoor or mild-climate builds the -8SN is a functional drop-in; for cold environments or wide-temperature specs, the -8TN is the correct choice.

What are the key technical specifications of ACS108-8TN-TR?

It is a logic-level sensitive-gate TRIAC rated for 800 V off-state voltage and 800 mA RMS on-state current. Gate trigger is 5 mA max at 1 V max, so a microcontroller GPIO can drive it directly. The hold current is 10 mA max. It can handle a non-repetitive surge of 13 A at 50 Hz or 13.7 A at 60 Hz.

What package does ACS108-8TN-TR come in?

It is supplied in a surface-mount SOT-223 package (TO-261-4, TO-261AA). The TR suffix means it ships in Tape & Reel; it is also available in Cut Tape for smaller quantities.