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STMicroelectronics ACS108-8SN-TR
- Part No.:
- ACS108-8SN-TR
- Manufacturer:
- STMicroelectronics
- Category:
- TRIACs
- Package:
- TO-261-4, TO-261AA
- Datasheet:
-
ACS108-8SN-TR.pdf
- Description:
- TRIAC SENS GATE 800V 0.8A SOT223
- Quantity:
- Payment:
- Shipping:
Inventory:30,060
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Product details
Overview
ACS108-8SN-TR from STMicroelectronics is a single-pole, 0.8 A RMS, 800 V blocking voltage AC switch with integrated overvoltage crowbar protection (VCL ≥ 850 V), negative gate trigger (IGT ≤ 10 mA), and SOT-223 package. It replaces discrete triac + snubber designs in low-power AC load switching for appliances and industrial controls.
For engineers reviewing the ACS108-8SN-TR datasheet, ACS108-8SN-TR pinout, ACS108-8SN-TR application, or ACS108-8SN-TR equivalent, this device offers verified surge ruggedness per IEC 61000-4-5 (2 kV line-to-line), direct microcontroller interface without external protection, and thermal performance validated up to 125 °C junction temperature.
Technical Context
The ACS108-8SN-TR uses A.S.D.® (Advanced Static Discharge) technology to implement an overvoltage crowbar structure that clamps turn-off transients from inductive loads and absorbs IEC 61000-4-5 surges up to 2 kV. Its gate-level shifter enables direct negative-current triggering from MCU GPIOs via a series resistor (e.g., 220 Ω).
It operates in Quadrants II and III only, requires no external snubber or varistor, and features dV/dt immunity ≥ 2000 V/μs at 125 °C. The common-tab SOT-223 package supports multi-device thermal sharing on a single heatsink pad.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| IT(RMS) | 0.8 A - Maximum continuous AC load current at 76 °C case temperature with 5 cm² copper area. |
| VDRM / VRRM | 800 V - Peak repetitive blocking voltage in both directions; ensures safe operation on 230 VAC mains with margin. |
| IGT | ≤ 10 mA - Maximum gate trigger current required to initiate conduction; enables direct drive from standard MCU outputs. |
| VCL | ≥ 850 V - Clamping voltage threshold before crowbar action; protects against inductive kickback and surge events. |
| dV/dt immunity | ≥ 2000 V/μs at 125 °C - Immunity to false triggering from fast transient noise on mains lines. |
| Rth(j-t) | 25 °C/W - Junction-to-tab thermal resistance; enables efficient heat transfer to shared cooling pad in multi-switch layouts. |
| I²t (fuse selection) | 1.1 A²s - Energy withstand capability for 10 ms pulse; used to size fuse coordination without derating. |
Pinout & Package
SOT-223 package with exposed metal tab (pin 4) electrically connected to COM terminal; thermally optimized for PCB copper area ≥ 5 cm²; RoHS-compliant, halogen-free, UL94 V0 epoxy.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| COM (Pin 1) | Common reference terminal | Connected to AC mains neutral or phase return path; internally tied to tab; serves as ground reference for gate driver. |
| OUT (Pin 2) | Load output terminal | Switched AC output to load (e.g., solenoid, lamp); carries full load current; voltage referenced to COM. |
| G (Pin 3) | Gate control input | Negative-current-triggered input; requires external resistor to MCU GPIO; sinking current initiates conduction. |
| Tab (Pin 4) | Thermal & electrical common | Electrically bonded to COM; provides primary thermal path to PCB heatsink; must be soldered to ≥5 cm² copper area. |
Key Features
| Feature | Design Value |
|---|---|
| Integrated overvoltage crowbar | Clamps turn-off transients ≥ 850 V and absorbs 2 kV IEC 61000-4-5 surges without external components. |
| Direct MCU interface | Accepts negative gate current (≤10 mA) from standard GPIOs via single series resistor-no level shifter or optocoupler needed. |
| No external snubber required | Eliminates varistors, RC networks, and associated BOM cost-reduces component count by up to 80% vs. triac-based solutions. |
| High-noise immunity | Withstands dV/dt ≥ 2000 V/μs and IEC 61000-4-4 burst noise at 125 °C junction temperature. |
| Multi-device thermal sharing | Common-tab SOT-223 allows mounting multiple ACS switches on same cooling pad-ideal for multi-channel appliance control boards. |
Applications
| Appliance Load Switching | Industrial Solenoid Control |
|---|---|
|
Use Scenario: On/off control of washing machine water valves, dishwasher dispensers, and HVAC air dampers. IC Role / Device Role / Timing Role: AC mains switch replacing mechanical relay; triggered once per cycle at zero-crossing or phase-angle point. Use Value: Eliminates relay contact wear and EMI; enables silent, maintenance-free operation with 0.8 A RMS rating matching typical solenoid loads. |
Use Scenario: Driving 24–230 VAC solenoids in PLC I/O modules, packaging machinery, and factory automation panels. IC Role / Device Role / Timing Role: Solid-state AC switch providing galvanically isolated load control via MCU GPIO with built-in surge protection. Use Value: Withstands 2 kV IEC 61000-4-5 surges on industrial mains; removes need for external MOVs-reducing board space and qualification effort. |
| Lamp Dimming Interface | Fan/Motor Start Control |
|
Use Scenario: Leading-edge dimming of incandescent and halogen lamps in smart lighting systems and architectural controls. IC Role / Device Role / Timing Role: Phase-controlled AC switch synchronized to zero-crossing detection; handles resistive lamp loads up to 0.8 A. Use Value: Low on-state voltage (≤1.3 V) minimizes power loss and self-heating during extended dimming cycles. |
Use Scenario: Soft-start and on/off control of low-power AC fans and blowers in HVAC units and medical equipment. IC Role / Device Role / Timing Role: Inductive load switch with VCL ≥ 850 V clamping to suppress turn-off voltage spikes from motor windings. Use Value: Prevents MOSFET/triac failure due to inductive kickback-no snubber design or layout tuning required. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar AC switch applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ACS108-6SN-TR | 600 V blocking voltage (VDRM/VRRM), otherwise identical pinout, specs, and crowbar architecture. | Suitable only for 115 VAC or SELV systems; not rated for 230 VAC mains with safety margin. | Select when operating on 100–120 VAC grids or isolated low-voltage AC circuits where 800 V rating is unnecessary. |
| BT134-600E | Standard 4-quadrant triac; no integrated crowbar; requires external snubber and MOV for surge protection. | Higher BOM cost and board area; lower dV/dt immunity (typically < 100 V/μs); needs gate driver isolation for MCU interface. | Choose only if legacy triac footprint compatibility is mandatory and system-level surge protection is already implemented externally. |
Compared with ACS108-6SN-TR, the -8SN variant adds 200 V headroom for robust 230 VAC operation; versus BT134-600E, it eliminates snubber design, reduces component count, and guarantees IEC 61000-4-5 compliance without layout-dependent tuning.
Availability
ACS108-8SN-TR is available at Aetrix Electronics and suitable for appliance control, industrial I/O modules, smart lighting interfaces, and HVAC fan management requiring stable component supply across long production lifecycles.
Supply support for ACS108-8SN-TR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, power, MCU, and sensor solutions for industrial, automotive, and consumer markets.
The ACS™ AC switch product line delivers integrated, surge-rugged solid-state alternatives to electromechanical relays and discrete triacs-targeting high-reliability, low-BOM-cost AC load control in white goods and factory automation.
FAQ
What is the minimum gate current required to trigger the ACS108-8SN-TR?
The ACS108-8SN-TR is specified with maximum IGT of 10 mA at 25 °C, but minimum guaranteed trigger current is 10% of that value (1 mA) under all conditions. It reliably triggers with 2–5 mA negative gate current from standard MCU GPIOs using a 220 Ω series resistor at 3.3 V or 5 V logic levels.
Can the ACS108-8SN-TR replace a mechanical relay in a 230 VAC, 0.5 A solenoid application?
Yes-it is qualified for 230 VAC mains with 800 V blocking voltage and 0.8 A RMS rating, exceeding the 0.5 A requirement. Its integrated crowbar handles solenoid turn-off energy without external snubbers, and its 2 kV IEC 61000-4-5 surge rating matches industrial relay reliability expectations.
Is the SOT-223 tab electrically isolated from the COM pin?
No-the metal tab is internally bonded to the COM terminal and must be connected to the same net. This design enables thermal conduction to the PCB while maintaining electrical reference integrity; it also allows multiple ACS devices to share a common heatsink pad without isolation barriers.
Does the ACS108-8SN-TR support phase-angle control or only zero-crossing switching?
It supports both modes: zero-crossing turn-on (for reduced EMI in resistive loads) and phase-angle control (for dimming or soft-start). Gate triggering timing determines conduction angle; the device latches until current falls below holding current (IH ≤ 10 mA), enabling precise half-cycle control.
ACS108-8SN-TR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- ACS™/A.S.D®
- Package/Case:
- TO-261-4, TO-261AA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Triac Type:
- Logic - Sensitive Gate
- Voltage - Off State:
- 800 V
- Current - On State (It (RMS)) (Max):
- 800 mA
- Voltage - Gate Trigger (Vgt) (Max):
- 1 V
- Current - Non Rep. Surge 50, 60Hz (Itsm):
- 13A, 13.7A
- Current - Gate Trigger (Igt) (Max):
- 10 mA
- Current - Hold (Ih) (Max):
- 10 mA
- Configuration:
- Single
- Operating Temperature:
- -30°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-223
ACS108-8SN-TR FAQ
1.How can I place an order for ACS108-8SN-TR through Aetrix?
Please submit a Request for Quotation (RFQ) for ACS108-8SN-TR on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for ACS108-8SN-TR reliable?
The price and inventory of ACS108-8SN-TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ACS108-8SN-TR is usually 5 days.
3.What payment methods are accepted for ACS108-8SN-TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ACS108-8SN-TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for ACS108-8SN-TR?
ACS108-8SN-TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your ACS108-8SN-TR order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for ACS108-8SN-TR?
For technical support, including ACS108-8SN-TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ACS108-8SN-TR requirements.
6.How does Aetrix verify that ACS108-8SN-TR is sourced from the original manufacturer or authorized distributors?
All ACS108-8SN-TR products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that ACS108-8SN-TR meets industry standards.
7.What is the process for return or replacement of ACS108-8SN-TR?
All ACS108-8SN-TR units undergo pre-shipment inspection (PSI). If there is an issue with ACS108-8SN-TR, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The ACS108-8SN-TR part is unused and in its original packaging.
Return procedure for ACS108-8SN-TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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