Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

Home > Products > Discrete Semiconductor Products > Thyristors > TRIACs

STMicroelectronics ACST1235-7GTR

Name: ACST1235-7GTR
Brand: STMicroelectronics
SKU: ACST1235-7GTR
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: ACST1235-7GTR

Manufacturer:: STMicroelectronics

Category:: TRIACs

Package:: TO-263-3, D2PAK (2 Leads + Tab), TO-263AB

Datasheet:: ACST1235-7GTR.pdf

Description:: TRIAC 700V 12A D2PAK

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:2,965

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

ACST1235-7GTR from STMicroelectronics is a 12 A, 700 V overvoltage-protected AC switch (Triac) with integrated crowbar clamping, designed for direct mains switching of inductive loads such as compressor motors and universal drum motors in home appliances. It delivers 2 kV/µs static dV/dt immunity at 125 °C, supports IEC 61000-4-4/4-5 compliance without external protection, and uses planar technology for high off-state reliability.

For engineers reviewing the ACST1235-7GTR datasheet, ACST1235-7GTR pinout, ACST1235-7GTR application, or ACST1235-7GTR equivalent, this device is selected for robust AC load control where transient immunity, snubberless operation, gate drive simplicity, and thermal stability under inrush conditions are critical design requirements.

Technical Context

The ACST1235-7GTR integrates a Triac structure with an on-die high-voltage clamping device that activates during line transients-either clamping low-energy spikes or crowbarring into conduction for ≤10 ms to dissipate high-energy surges per IEC 61000-4-5. Its planar construction ensures stable blocking behavior up to 125 °C junction temperature.

It operates in all four quadrants with guaranteed IGT ≤35 mA at 25 °C and maintains ≥2000 V/µs static dV/dt immunity even at maximum rated junction temperature. The device sustains 12 A RMS current with R_th(j-c) = 1.5 °C/W (D2PAK), enabling direct heatsink mounting without auxiliary snubbers for inductive loads like fridge compressors.

Key Specifications

Parameter	Value and Actual Design Meaning
IT(RMS)	12 A - Sustains continuous sinusoidal load current up to 12 A without derating when mounted on heatsink with R_th(j-c) ≤1.5 °C/W
VDRM / VRRM	700 V - Blocks 700 V peak AC line voltage, compatible with 230 Vrms mains with safety margin
dV/dt (static)	≥2000 V/µs @ 125 °C - Immune to fast transients per IEC 61000-4-4 without false triggering
VCL	≥850 V @ 25 °C - Clamps inductive turn-off energy and absorbs line surges up to 2 kV per IEC 61000-4-5
IGT	≤35 mA @ 25 °C - Gate trigger current low enough for direct MCU GPIO drive via series resistor
Rd	≤30 mΩ @ 125 °C - Low on-state resistance minimizes conduction loss and self-heating at full load
VTM	≤1.5 V @ 17 A, 25 °C - Predictable forward voltage drop enables accurate power loss calculation

Pinout & Package

D2PAK (TO-263) package: surface-mount, single-ended tab with three leads; thermally optimized for PCB copper area (1 cm² Cu recommended); UL94 V0 epoxy; RoHS-compliant ECOPACK®2.

Pin/Terminal	Circuit Role	Design Meaning
G	Gate	Low-current control input (≤35 mA); referenced to COM; triggers conduction in all quadrants
OUT	Main output terminal (anode 2)	Carries full load current; connected to AC load; electrically isolated from COM by internal Triac structure
COM	Common terminal (anode 1 / MT1)	Reference node for gate and load return path; tied to neutral or one side of AC source in typical configuration

Key Features

Feature	Design Value
Integrated overvoltage crowbar protection	Self-activates during IEC 61000-4-5 surges up to 2 kV, eliminating need for MOVs or TVS diodes
Snubberless inductive switching	Drives 12 A compressor or universal motor without external RC snubber due to controlled turn-off commutation
High-temperature dV/dt immunity	Maintains ≥2000 V/µs static noise immunity at 125 °C junction temperature-critical for enclosed appliance environments
Planar Triac structure	Ensures stable off-state leakage (<1.5 mA @ 125 °C) and long-term reliability under thermal cycling
MCU-compatible gate drive	Accepts ≤35 mA gate current; enables direct connection to 3.3 V/5 V microcontroller outputs with simple series resistor

Applications

Compressor Motor Control

Universal Drum Motor Control

Use Scenario: Controlling refrigerator or air conditioner compressor startup and run cycles in sealed, thermally constrained enclosures.

IC Role / Device Role / Timing Role: AC mains switch replacing electromechanical relays; handles inrush currents >6× rated RMS and withstands repeated 2 kV line surges.

Use Value: Eliminates relay wear-out and contact arcing; reduces BOM count by removing external snubber and overvoltage protection components.

Use Scenario: Speed and direction control of washing machine drum motors using phase-angle or burst-fire AC switching.

IC Role / Device Role / Timing Role: Solid-state AC switch interfacing directly with MCU PWM logic; operates across all quadrants for bidirectional torque control.

Use Value: Enables precise zero-crossing synchronized switching with <10 µs timing jitter; supports variable-speed operation without audible coil whine.

Smart Appliance Mains Interface

Industrial AC Load Sequencing

Use Scenario: Mains-powered smart home devices (e.g., IoT-enabled ovens, dishwashers) requiring certified surge immunity and remote on/off control.

IC Role / Device Role / Timing Role: Primary isolation and switching element between AC mains and load; certified to IEC 61000-4-4/4-5 for EMC compliance.

Use Value: Meets global safety certifications (EN 60335, UL 60730) without redesigning PCB layout for external protection circuitry.

Use Scenario: Programmable logic-controlled sequencing of multiple AC loads (e.g., HVAC actuators, conveyor heaters) in factory automation panels.

IC Role / Device Role / Timing Role: High-reliability AC switch in DIN-rail mounted controllers; operates continuously at 47 °C ambient with 12 A sustained load.

Use Value: Delivers 12 A RMS with R_th(j-a) = 45 °C/W (1 cm² Cu), enabling compact thermal design without forced air cooling.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
ACST1210-7GTR	Lower IGT (≤10 mA) but reduced dV/dt immunity (200 V/µs)	Better suited for low-noise, low-power MCU drive; less robust in high-interference industrial mains environments	Select when gate drive current budget is <10 mA and system EMI is tightly controlled
BTB12-700CW	No integrated crowbar; requires external MOV + snubber; dV/dt = 1000 V/µs max	Lacks self-protection against IEC 61000-4-5 surges; higher component count and board space	Select only if cost sensitivity outweighs certification and reliability requirements

Compared with ACST1210-7GTR, ACST1235-7GTR trades lower gate sensitivity for superior transient immunity-making it preferred for unfiltered mains environments. Versus BTB12-700CW, it eliminates external protection components while delivering higher dV/dt and verified surge survivability.

Availability

ACST1235-7GTR is available at Aetrix Electronics and suitable for compressor motor control, universal drum motor switching, and smart appliance mains interface applications requiring stable component supply, long-lifecycle support, and certified surge immunity.

Supply support for ACST1235-7GTR 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™/ACST family is engineered specifically for solid-state AC load control in home appliances and industrial systems-emphasizing ruggedness, integration, and compliance with international surge immunity standards.

FAQ

What is the maximum continuous case temperature for reliable operation?

The ACST1235-7GTR supports continuous operation at T_c = 104 °C when mounted on a heatsink with R_th(j-c) ≤1.5 °C/W. At this condition, it delivers full 12 A RMS current without derating. Exceeding 104 °C case temperature risks exceeding the 125 °C maximum junction temperature, triggering thermal shutdown or accelerated degradation.

Can ACST1235-7GTR replace a mechanical relay in compressor applications?

Yes-it is qualified for snubberless switching of compressor motors up to 12 A RMS, including inrush currents exceeding 60 A for short durations. Its integrated crowbar protection handles line transients that would degrade relay contacts, and its planar Triac structure ensures >100,000 switching cycles without wear-out-unlike electromechanical relays.

Does the device require a heat sink in standard D2PAK PCB mounting?

A minimum 1 cm² copper pour is required beneath the tab for thermal performance matching the datasheet's R_th(j-a) = 45 °C/W rating. For continuous 12 A operation at ambient >47 °C, an external heatsink is recommended. At ≤5 A RMS and 25 °C ambient, the D2PAK can operate without additional heatsinking using only the specified PCB copper area.

How does the crowbar protection behave during a 2 kV IEC 61000-4-5 surge?

During a 2 kV surge, the internal clamping device activates within nanoseconds: for low-energy spikes, it clamps voltage to ≤850 V; for high-energy events, it crowbars into conduction for <10 ms, diverting surge current through the load. After the surge, it recovers full blocking capability at the next zero-crossing-no reset or latch-up occurs.

ACST1235-7GTR Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: ACS™/A.S.D®

Package/Case:: TO-263-3, D2PAK (2 Leads + Tab), TO-263AB

Packaging:: Tape & Reel (TR)

Product Status:: Active

Triac Type:: Standard

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):: 35 mA

Current - Hold (Ih) (Max):: 50 mA

Configuration:: Single

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

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: D2PAK

ACST1235-7GTR FAQ

1.How can I place an order for ACST1235-7GTR through Aetrix?

Please submit a Request for Quotation (RFQ) for ACST1235-7GTR 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 ACST1235-7GTR reliable?

The price and inventory of ACST1235-7GTR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ACST1235-7GTR is usually 5 days.

3.What payment methods are accepted for ACST1235-7GTR?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ACST1235-7GTR transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for ACST1235-7GTR?

ACST1235-7GTR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your ACST1235-7GTR 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 ACST1235-7GTR?

For technical support, including ACST1235-7GTR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ACST1235-7GTR requirements.

6.How does Aetrix verify that ACST1235-7GTR is sourced from the original manufacturer or authorized distributors?

All ACST1235-7GTR 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 ACST1235-7GTR meets industry standards.

7.What is the process for return or replacement of ACST1235-7GTR?

All ACST1235-7GTR units undergo pre-shipment inspection (PSI). If there is an issue with ACST1235-7GTR, 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 ACST1235-7GTR part is unused and in its original packaging.

Return procedure for ACST1235-7GTR:

1.Submit a request within 90 days.

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

Tech Hub

2026-09-10 Schmitt Trigger Explained: Hysteresis, Circuits, Inverters and Applications

Schmitt triggers use separate rising and falling thresholds to stabilize slow or noisy signals. This guide covers hysteresis, 74HC14 and 74HCT14 selection, comparator calculations, RC oscillators and p…

2026-09-09 Counterfeit Electronic Components: How to Detect, Authenticate, and Test Suspect Parts

Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …

2026-09-08 Obsolete Electronic Components: How to Source and Evaluate Replacements

A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.

2026-09-07 TTL vs CMOS Logic Levels: 74HC and 74HCT Compatibility Explained

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.

2026-09-04 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

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.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

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…

2026-09-02 74HC595 Pinout, Timing, Output Current, and Applications

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…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

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…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

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 …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

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…