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Home > Products > Discrete Semiconductor Products > Thyristors > TRIACs

STMicroelectronics ACST1210-7T

Name: ACST1210-7T
Brand: STMicroelectronics
SKU: ACST1210-7T
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: ACST1210-7T

Manufacturer:: STMicroelectronics

Category:: TRIACs

Package:: TO-220-3

Datasheet:: ACST1210-7T.pdf

Description:: TRIAC SENS GATE 700V 12A TO220

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Product details

Overview

ACST1210-7T from STMicroelectronics is a 12 A, 700 V overvoltage-protected AC switch (Triac with integrated crowbar clamping), designed for direct MCU-driven static switching of inductive AC loads up to 12 A RMS without external snubbers. It features low gate trigger current (IGT < 10 mA), high static dV/dt immunity (>200 V/µs at 125 °C), and meets IEC 61000-4-5 surge and IEC 61000-4-4 fast transient immunity standards in appliance motor control.

For engineers reviewing the ACST1210-7T datasheet, ACST1210-7T pinout, ACST1210-7T application, or ACST1210-7T equivalent, this device serves as a self-protected, snubberless Triac replacement for compressor and universal motor drive in home appliances - requiring precise gate drive design, thermal derating validation, and IEC-compliant transient resilience assessment.

Technical Context

The ACST1210-7T integrates a planar Triac structure with an on-die high-voltage clamping device that activates during line transients (e.g., inductive turn-off spikes or IEC 61000-4-5 surges), folding the device into a low-impedance on-state for ≤10 ms to safely dissipate energy through the load. Its crowbar action preserves blocking capability after zero-crossing recovery.

It operates in all four quadrants with guaranteed IGT ≤10 mA at 25 °C and maintains ≥200 V/µs static dV/dt immunity even at Tj = 125 °C. The device's dynamic resistance (Rd ≤30 mΩ) and low on-state voltage (VTM ≤1.5 V at 17 A, 25 °C) minimize conduction losses in medium-power AC motor drive applications.

Key Specifications

Parameter	Value and Actual Design Meaning
IT(RMS)	12 A - Supports continuous AC load current up to washing machine drum motors or refrigerator compressors without forced cooling.
VDRM / VRRM	700 V - Blocks peak mains voltages up to 495 VAC (e.g., 230 VAC + 30% tolerance) with safety margin.
IGT (max)	10 mA - Enables direct drive from standard MCU GPIO pins via a single series resistor (no buffer stage required).
dV/dt (min)	200 V/µs @ 125 °C - Prevents false triggering from EMI or commutation noise in noisy industrial environments.
VCL (min)	850 V @ 25 °C - Clamps transient overvoltages above line peak, eliminating need for external MOVs or TVS diodes.
Rth(j-c)	1.5 °C/W - Enables efficient heat transfer to heatsink; allows 8.5 W dissipation at ΔT = 12.75 °C case-to-heatsink rise.
TO-220AB Package	Standard through-hole power package with insulated tab; compatible with legacy mounting hardware and thermal interface materials.

Pinout & Package

ACST1210-7T uses the TO-220AB package: three-terminal, insulated tab, vertical mounting orientation, with pin 1 = COM (main terminal 1), pin 2 = OUT (main terminal 2), pin 3 = G (gate). Tab is electrically isolated and thermally connected to the die substrate.

Pin/Terminal	Circuit Role	Design Meaning
COM	Main terminal 1 (MT1)	Reference node for gate triggering; connects to neutral or low-side return path in AC bridge configurations.
OUT	Main terminal 2 (MT2)	High-current output path to load; carries full RMS load current and surge peaks up to 126 A (non-repetitive).
G	Gate control input	Low-energy trigger input; requires ≤10 mA DC pulse to initiate conduction; polarity-insensitive across quadrants I–III.

Key Features

Feature	Design Value
Integrated overvoltage crowbar protection	Clamps transients ≥850 V and switches to safe on-state for ≤10 ms - eliminates external MOVs and reduces BOM count by 1–2 components.
Snubberless inductive load switching	Withstands commutation stress from 12 A universal motors or compressors without RC snubber networks - simplifies PCB layout and improves reliability.
MCU-direct gate drive capability	Guaranteed IGT ≤10 mA enables robust triggering from 3.3 V or 5 V microcontrollers using only a 330 Ω–1 kΩ series resistor.
High thermal robustness	Rth(j-c) = 1.5 °C/W and Tj max = +125 °C support sustained operation under compressor inrush and high-torque conditions without thermal shutdown.

Applications

Washing Machine Drum Motor Control

Refrigerator Compressor Drive

Use Scenario: Precise speed and direction control of universal motors in front-load washers using phase-angle or burst-fire AC switching.

IC Role / Device Role / Timing Role: Snubberless AC switch replacing discrete Triac + MOV + snubber; triggered synchronously to zero-crossing for EMI reduction.

Use Value: Eliminates 3 external passive components while maintaining IEC 61000-4-4 immunity and enabling compact motor driver PCBs.

Use Scenario: Start-stop and run-cycle control of hermetic compressors in domestic refrigerators with high inrush current (≥6× rated).

IC Role / Device Role / Timing Role: High-dI/dt-rated AC switch handling 120 A surge peaks (20 ms, 50 Hz); activated at zero-crossing to limit turn-on stress.

Use Value: Withstands repeated compressor inrush without degradation; clamps line transients up to 2 kV per IEC 61000-4-5 without derating.

Air Conditioner Fan Motor Control

Industrial AC Solenoid Actuation

Use Scenario: Variable-speed control of PSC or shaded-pole fans in split-system AC units using leading-edge phase control.

IC Role / Device Role / Timing Role: Low-IGT Triac providing clean turn-on at programmable phase angles; gate driven by optocoupler-isolated MCU output.

Use Value: Reduces audible coil whine vs. standard Triacs due to consistent triggering threshold and low VTM (≤1.5 V).

Use Scenario: Reliable on/off cycling of 240 VAC solenoids in PLC-controlled packaging machinery with frequent mechanical shock and EMI exposure.

IC Role / Device Role / Timing Role: Ruggedized AC switch with 200 V/µs dV/dt immunity preventing spurious turn-on from contactor-induced transients.

Use Value: Achieves >100,000 cycles MTBF without gate protection circuitry; eliminates field failures from fast dv/dt events.

Equivalent & Alternatives

The following parts are listed as comparable options for similar AC switch applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
ACST1235-7T	Higher IGT (≤35 mA) but ≥2000 V/µs dV/dt immunity at 125 °C - optimized for ultra-noisy environments.	Preferred where gate drive current is abundant but EMI immunity is critical (e.g., industrial inverters near VFDs).	Select when system-level EMC testing shows marginal dV/dt margin with ACST1210-7T; not drop-in due to higher IGT.
BTA12-600BWRG	Standard 12 A Triac (600 V), no integrated crowbar; requires external MOV + RC snubber for IEC 61000-4-5 compliance.	Suitable only if board space and BOM cost allow added protection components and thermal derating for snubber losses.	Choose only if legacy design reuse mandates pin-compatible Triac; adds ≥3 components and reduces reliability vs. ACST1210-7T.

Compared with ACST1235-7T, the ACST1210-7T trades higher dV/dt immunity for lower gate drive burden - ideal for MCU-constrained designs. Against BTA12-600BWRG, it delivers verified surge protection in a single device, reducing footprint, assembly cost, and failure modes.

Availability

ACST1210-7T is available at Aetrix Electronics and suitable for washing machine motor control, refrigerator compressor drive, and air conditioner fan regulation requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant TO-220AB packaging.

Supply support for ACST1210-7T 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, digital, and mixed-signal ICs for automotive, industrial, and consumer markets.

The ACST™ family is ST's application-specific discrete (A.S.D.) power switch product line, engineered specifically for snubberless, self-protected AC load control in white goods and industrial equipment - prioritizing surge resilience, gate simplicity, and thermal robustness.

FAQ

What is the maximum allowable gate resistor value for direct MCU drive?

The ACST1210-7T guarantees IGT ≤10 mA at 25 °C. With a 5 V MCU GPIO, a 330 Ω resistor limits gate current to ~12 mA - within safe operating range. At 3.3 V, use ≤220 Ω to ensure ≥10 mA minimum under worst-case VGS drop and temperature drift. Exceeding 1 kΩ risks unreliable triggering above 85 °C junction temperature.

Does ACST1210-7T require a heatsink in 12 A continuous operation?

Yes - at 12 A RMS and 1.5 V on-state drop, power dissipation reaches ~18 W. With Rth(j-c) = 1.5 °C/W and max Tj = 125 °C, a heatsink maintaining Tc ≤ 75 °C (ΔT = 50 °C) is required. Without forced airflow, a 50 cm² aluminum heatsink with thermal interface pad is recommended per ST application note AN4312.

Can ACST1210-7T replace a standard Triac in an existing design without layout changes?

Yes, if the original design uses TO-220AB Triacs (e.g., BT139-600), pinout is identical (COM–OUT–G). However, remove external MOVs and snubber RC networks - their presence may interfere with crowbar operation. Verify gate drive timing: ACST1210-7T has faster turn-on but same zero-crossing synchronization requirements.

How many IEC 61000-4-5 surge events can ACST1210-7T withstand?

Per STMicroelectronics documentation, the device withstands ≥10 non-repetitive 2 kV surges (1.2/50 µs voltage waveform) on each AC line polarity, provided the load limits current and case temperature remains ≤104 °C. Post-surge recovery occurs automatically after the next zero-crossing; no reset or retriggering is needed.

ACST1210-7T Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: ACS™/A.S.D®

Package/Case:: TO-220-3

Packaging:: Tube

Product Status:: Obsolete

Triac Type:: Logic - Sensitive Gate

Voltage - Off State:: 700 V

Current - On State (It (RMS)) (Max):: 12 A

Voltage - Gate Trigger (Vgt) (Max):: 1 V

Current - Non Rep. Surge 50, 60Hz (Itsm):: 120A, 126A

Current - Gate Trigger (Igt) (Max):: 10 mA

Current - Hold (Ih) (Max):: 30 mA

Configuration:: Single

Operating Temperature:: -40°C ~ 125°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-220

ACST1210-7T FAQ

1.How can I place an order for ACST1210-7T through Aetrix?

Please submit a Request for Quotation (RFQ) for ACST1210-7T 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 ACST1210-7T reliable?

The price and inventory of ACST1210-7T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ACST1210-7T is usually 5 days.

3.What payment methods are accepted for ACST1210-7T?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ACST1210-7T transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for ACST1210-7T?

ACST1210-7T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your ACST1210-7T 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 ACST1210-7T?

For technical support, including ACST1210-7T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ACST1210-7T requirements.

6.How does Aetrix verify that ACST1210-7T is sourced from the original manufacturer or authorized distributors?

All ACST1210-7T 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 ACST1210-7T meets industry standards.

7.What is the process for return or replacement of ACST1210-7T?

All ACST1210-7T units undergo pre-shipment inspection (PSI). If there is an issue with ACST1210-7T, 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 ACST1210-7T part is unused and in its original packaging.

Return procedure for ACST1210-7T:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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