My Inquiry
My Account
STMicroelectronics ACS108-8SP-TR
- Part No.:
- ACS108-8SP-TR
- Manufacturer:
- STMicroelectronics
- Category:
- TRIACs
- Package:
- TO-261-3
- Datasheet:
-
ACS108-8SP-TR.pdf
- Description:
- TRIACS OVERVOLTAGE PROTECTED AC
- Quantity:
- Payment:
- Shipping:
Inventory:3,984
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
ACS108-8SP-TR from STMicroelectronics is an 800 V, 0.8 A RMS overvoltage-protected AC switch (ACS) with integrated crowbar clamping and gate-level shifter. It replaces discrete triac + snubber + varistor solutions in AC mains load switching, enabling IEC 61000-4-5 surge compliance without external protection components. Used for driving solenoids, valves, low-power motors, and lamps in industrial controls and home appliances.
For engineers reviewing the ACS108-8SP-TR datasheet, ACS108-8SP-TR pinout, ACS108-8SP-TR application, or ACS108-8SP-TR equivalent, this page delivers verified electrical specs, validated SOT223-2L package mapping, confirmed crowbar clamping behavior at ≥850 V, dV/dt immunity ≥2000 V/μs, and direct microcontroller interface capability via negative gate current triggering.
Technical Context
The ACS108-8SP-TR integrates an overvoltage crowbar structure that clamps transient energy during inductive turn-off and absorbs IEC 61000-4-5 surges up to 2 kV peak. Its gate-level shifter isolates digital controllers from mains-referenced switching paths while enabling direct drive with a single series resistor (e.g., 220 Ω).
Triggered by negative gate current (IGT ≤ 10 mA), it operates bidirectionally across quadrants II and III. Clamping voltage VCL ≥ 850 V at 0.1 mA ensures safe dissipation of inductive energy without external snubbers, and its dI/dt rating of 100 A/μs supports robust commutation under high-inductance loads up to 15 H.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| IT(RMS) | 0.8 A RMS - Supports continuous switching of resistive/inductive loads up to 180° conduction angle at 76 °C case temperature. |
| VDRM / VRRM | 800 V - Blocks full AC mains cycles (e.g., 230 Vrms, 50 Hz) with margin against transients and line variations. |
| VCL | ≥850 V - Clamps inductive turn-off overvoltage and IEC 61000-4-5 surges, eliminating need for external varistors or snubbers. |
| dV/dt immunity | ≥2000 V/μs - Prevents false triggering from ESD bursts (IEC 61000-4-4) and fast mains transients without gate filtering. |
| IGT | ≤10 mA - Enables direct drive from standard MCU GPIO pins using only a series resistor (e.g., 220 Ω at 3.3 V). |
| Rth(j-t) | 25 °C/W - Thermal resistance from junction to tab enables effective heatsinking through PCB copper area ≥5 cm². |
| VTM | ≤1.3 V - Low on-state voltage drop minimizes power loss and self-heating at rated current. |
Pinout & Package
SOT223-2L package with exposed thermal tab (pin 2), UL94 V0 epoxy, lead-free plating, and halogen-free molding resin. Tab is electrically connected to COM terminal for thermal and functional grounding.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| COM | Common reference terminal | Connects to AC mains neutral or return path; serves as thermal tab anchor and gate driver reference. |
| OUT | Switched output terminal | Connects to load (e.g., solenoid, lamp); carries full AC load current and withstands 800 V blocking voltage. |
| G | Negative gate input | Receives gate current flowing *out* of pin (sinking); triggered by MCU GPIO pulled low through series resistor. |
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 microcontroller interface | Accepts negative gate current (≤10 mA) - eliminates level-shifting ICs and reduces BOM count by up to 80%. |
| High dV/dt immunity | ≥2000 V/μs at 125 °C - prevents spurious turn-on from ESD bursts and noisy AC environments. |
| High creepage distance | 3.8 mm in SOT223-2L - meets reinforced insulation requirements for mains-connected equipment. |
| Inductive load optimized | Supports turn-off of loads up to 15 H (e.g., water valves) with linear clamped energy dissipation. |
Applications
| Smart Home Valve Control | Industrial Solenoid Driver |
|---|---|
|
Use Scenario: Precise on/off control of water/gas valves in smart thermostats and irrigation systems. IC Role / Device Role / Timing Role: AC mains switch replacing triac+snubber, providing zero-crossing–independent turn-off with clamped inductive kickback. Use Value: Eliminates external varistor and RC snubber, reducing board space by >50% while maintaining IEC 61000-4-5 compliance. |
Use Scenario: Driving 24–230 VAC solenoids in PLC I/O modules and factory automation panels. IC Role / Device Role / Timing Role: Bidirectional AC switch with gate-level isolation, triggered by isolated MCU outputs. Use Value: Withstands repetitive 15 H inductive turn-off energy without degradation, enabling >10⁵ cycle lifetime. |
| Appliance Lamp Dimming | Fan Speed Control Module |
|
Use Scenario: Phase-angle dimming of incandescent/halogen lamps in ovens, coffee makers, and lighting fixtures. IC Role / Device Role / Timing Role: High-noise-immunity AC switch accepting gate signals from PWM-capable microcontrollers. Use Value: dV/dt ≥2000 V/μs prevents misfiring during rapid phase-cut transitions in noisy appliance environments. |
Use Scenario: Speed control of shaded-pole and PSC fans in HVAC units and air purifiers. IC Role / Device Role / Timing Role: Mains-referenced load switch with integrated clamping for motor back-EMF suppression. Use Value: VCL ≥850 V safely dissipates inductive energy during abrupt fan stop commands, avoiding MOSFET/triac failure. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar AC switch applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| ACS108-6SP-TR | 600 V VDRM instead of 800 V; identical IT(RMS), IGT, and crowbar architecture. | Limited to 120 VAC or derated 230 VAC use; lower surge margin in high-voltage mains environments. | Select when operating exclusively on 120 VAC systems or where cost optimization outweighs 800 V headroom. |
| BTB08-600SL | Standard 8 A triac without integrated crowbar; requires external snubber and MOV for IEC 61000-4-5 compliance. | Higher component count and board area; no built-in dV/dt immunity - susceptible to false triggering in noisy settings. | Choose only if legacy triac design reuse is required and external protection components are acceptable. |
Compared with ACS108-6SP-TR, the ACS108-8SP-TR provides 33% higher blocking voltage for robust 230 VAC operation and superior surge resilience; versus BTB08-600SL, it reduces BOM count by eliminating snubber/MOV and improves noise immunity without sacrificing load current capability.
Availability
ACS108-8SP-TR is available at Aetrix Electronics and suitable for smart home valve control, industrial solenoid drivers, and appliance lamp dimming requiring stable component supply, long-term lifecycle support, and IEC-compliant surge ruggedness.
Supply support for ACS108-8SP-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 silicon solutions for automotive, industrial, and consumer markets since 1987.
The ACS family targets solid-state AC load switching with integrated protection - engineered specifically to replace triac-based designs burdened by snubbers, varistors, and layout constraints in space-constrained, safety-critical applications.
FAQ
What is the recommended gate resistor value for driving ACS108-8SP-TR from a 3.3 V MCU?
A 220 Ω resistor is specified in the datasheet for 3.3 V MCU operation, delivering ~10 mA gate current (within IGT ≤ 10 mA max). This ensures reliable triggering while limiting gate power dissipation to <0.1 W. Lower values risk exceeding IGM (1 A peak) during transients; higher values may fail to meet IGT at elevated temperature.
Can ACS108-8SP-TR drive a 15 H water valve without external protection?
Yes - the integrated crowbar clamps turn-off overvoltage to ≥850 V and safely dissipates stored inductive energy, as validated in Figure 16 of DS14330. No snubber or varistor is needed, even for valves with up to 15 H inductance, provided RMS current stays within 0.8 A and thermal design meets Rth(j-t) = 25 °C/W.
Does ACS108-8SP-TR require zero-crossing detection for reliable operation?
No - unlike standard triacs, it does not rely on zero-crossing for turn-on or turn-off. It can be triggered at any point in the AC cycle and uses crowbar action to manage inductive turn-off regardless of current phase, enabling precise timing control in phase-angle dimming and fast solenoid actuation.
How does ACS108-8SP-TR achieve IEC 61000-4-5 compliance without external components?
It combines two internal protections: clamping of low-energy spikes (via avalanche diode structure) and controlled breakover during high-energy surges (up to 2 kV), both referenced to the IEC 61000-4-5 test circuit in Figure 17. The crowbar action limits voltage across OUT-COM to ≤VCL, preventing downstream component stress without MOVs or TVS diodes.
ACS108-8SP-TR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- ECOPACK®
- Package/Case:
- TO-261-3
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Triac Type:
- Alternistor - Snubberless
- 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:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOT-223-2
ACS108-8SP-TR FAQ
1.How can I place an order for ACS108-8SP-TR through Aetrix?
Please submit a Request for Quotation (RFQ) for ACS108-8SP-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 ACS108-8SP-TR reliable?
The price and inventory of ACS108-8SP-TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ACS108-8SP-TR is usually 5 days.
3.What payment methods are accepted for ACS108-8SP-TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ACS108-8SP-TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for ACS108-8SP-TR?
ACS108-8SP-TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your ACS108-8SP-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 ACS108-8SP-TR?
For technical support, including ACS108-8SP-TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ACS108-8SP-TR requirements.
6.How does Aetrix verify that ACS108-8SP-TR is sourced from the original manufacturer or authorized distributors?
All ACS108-8SP-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 ACS108-8SP-TR meets industry standards.
7.What is the process for return or replacement of ACS108-8SP-TR?
All ACS108-8SP-TR units undergo pre-shipment inspection (PSI). If there is an issue with ACS108-8SP-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 ACS108-8SP-TR part is unused and in its original packaging.
Return procedure for ACS108-8SP-TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
ACS108-8SP-TR Tags
-
Z0103NN5AA4
STMicroelectronics
-
Z0107MNT1G
Littelfuse Inc.
-
Z0103MNT1G
Littelfuse Inc.
;;2.jpg)
-
T405-800B-TR
STMicroelectronics
-
T835-600B-TR
STMicroelectronics
.JPG)
-
2N6073BG
Littelfuse Inc.
-
2N6075BG
Littelfuse Inc.
-
BTA08-600CWRG
STMicroelectronics
-
T835H-6G-TR
STMicroelectronics
-
BTA16-800BRG
STMicroelectronics
-
T1210-800G-TR
STMicroelectronics
-
MAC4DHMT4G
Littelfuse Inc.
Tech Hub
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
