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Home > Products > Discrete Semiconductor Products > Thyristors > TRIACs

STMicroelectronics ACST830-8FP

Name: ACST830-8FP
Brand: STMicroelectronics
SKU: ACST830-8FP
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: ACST830-8FP

Manufacturer:: STMicroelectronics

Category:: TRIACs

Package:: TO-220-3 Full Pack

Datasheet:: ACST830-8FP.pdf

Description:: TRIAC 800V 8A TO220FP

Quantity:: RFQ Add To RFQ list

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Inventory:4,562

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Product details

Overview

ACST830-8FP from STMicroelectronics is an 8 A, 800 V RMS overvoltage-protected AC switch in a TO-220FPAB insulated package, integrating a triac with built-in crowbar clamping (V_CL ≥ 850 V) for IEC 61000-4-5 transient immunity. It drives universal drum motors in washing machines and compressors in refrigerators without external snubbers or MOVs, leveraging planar technology for high off-state reliability and dV/dt immunity >2000 V/µs at 125 °C.

For engineers reviewing the ACST830-8FP datasheet, ACST830-8FP pinout, ACST830-8FP application, or ACST830-8FP equivalent, this device is selected for robust AC mains switching in home appliance motor control where self-protected turn-off energy absorption, high thermal margin (R_th(j-c) = 3.6 °C/W), and UL-certified 2000 V_RMS insulation are critical design requirements.

Technical Context

The ACST830-8FP implements an integrated triac structure with voltage-triggered crowbar protection: when line transients exceed V_CL (min. 850 V), it latches on for <10 ms to safely dissipate surge energy through the load-enabling compliance with IEC 61000-4-5 2 kV surge testing. Its planar junction ensures stable dV/dt immunity across temperature (≥2000 V/µs at T_j = 125 °C) and eliminates need for external RC snubbers in inductive motor drive.

It operates in all four quadrants with gate trigger current ≤30 mA at 25 °C and holding current ≤30 mA, supporting microcontroller-driven zero-crossing or phase-angle control. The TO-220FPAB package provides reinforced insulation (2000 V_RMS, UL E81734), enabling direct mounting on non-isolated heatsinks in Class I appliances.

Key Specifications

Parameter	Value and Actual Design Meaning
IT(RMS)	8 A - Sustains continuous motor load current up to universal drum motors (e.g., washing machine spin cycle) without derating at T_c = 91 °C.
VDRM / VRRM	800 V - Blocks full AC mains peak voltage (e.g., 230 V_RMS × √2 ≈ 325 V) with 2.5× safety margin for line surges.
dV/dt (static)	>2000 V/µs - Immune to fast transients per IEC 61000-4-4, eliminating false triggering in noisy industrial environments.
VCL (clamping)	≥850 V - Activates crowbar protection before destructive overvoltage occurs, absorbing inductive turn-off spikes without external components.
Rth(j-c)	3.6 °C/W - Enables efficient heat transfer to heatsink; allows 8 A operation with ≤29 °C temperature rise above case at full load.
Insulation Voltage	2000 V_RMS - UL-certified isolation (File E81734) permits safe use in double-insulated appliances without additional barrier materials.
IGT	≤30 mA - Compatible with standard MCU GPIOs or low-power drivers; no external gate amplifier required.

Pinout & Package

ACST830-8FP uses the TO-220FPAB package: insulated plastic body with metal tab isolated from internal die, rated for 2000 V_RMS insulation, UL E81734 certified, and designed for direct heatsink mounting without insulating pads.

Pin/Terminal	Circuit Role	Design Meaning
G	Gate	Low-energy trigger input; accepts ≤30 mA pulse to initiate conduction in any quadrant; referenced to COM.
COM	Common Terminal	Reference node for gate drive and load return path; electrically tied to internal triac cathode structure.
OUT	Main Output Terminal	Carries full load current (up to 8 A RMS); connected to AC load (e.g., motor winding); bidirectional conduction path.

Key Features

Feature	Design Value
Integrated overvoltage crowbar	Clamps transients ≥850 V and latches on <10 ms to shunt surge energy through load-eliminates MOVs and snubber networks.
High dV/dt immunity	Guaranteed >2000 V/µs at 125 °C-prevents false triggering during EMI-rich motor commutation or relay bounce.
UL-certified insulation	2000 V_RMS isolation (UL File E81734)-enables single-layer PCB layout and direct heatsink mounting in Class I appliances.
No snubber required	Drives 8 A inductive loads (e.g., fridge compressor) without external RC network-reduces BOM count and board space by ≥3 components.
Planar junction reliability	High off-state blocking stability over temperature and lifetime-ensures >10-year field reliability in consumer motor control.

Applications

Washing Machine Drum Motor Control

Refrigerator Compressor Drive

Use Scenario: Phase-controlled speed regulation of universal motor during wash/spin cycles with frequent direction reversal and high inrush currents.

IC Role / Device Role / Timing Role: AC mains switch replacing mechanical relays; handles bidirectional current and zero-crossing synchronized firing.

Use Value: Eliminates relay contact wear and acoustic noise; withstands 8 A inrush without snubber; crowbar protection absorbs motor back-EMF spikes.

Use Scenario: On/off cycling of hermetic compressor in variable-temperature refrigeration systems with ambient temperature swings from –20 °C to +45 °C.

IC Role / Device Role / Timing Role: Solid-state replacement for electromechanical contactors; provides precise turn-on timing and fail-safe turn-off.

Use Value: Maintains ≥2000 V/µs dV/dt immunity across full operating range; R_th(j-c) = 3.6 °C/W enables compact heatsink design in sealed compressor enclosures.

Air Conditioner Fan Motor Switching

Industrial Pump Motor Starter

Use Scenario: Static switching of PSC (permanent split capacitor) fan motors in inverter-based HVAC units requiring silent, jitter-free airflow control.

IC Role / Device Role / Timing Role: High-noise-immunity AC switch interfaced with MCU PWM outputs for soft-start and speed modulation.

Use Value: Withstands 2 kV line surges per IEC 61000-4-5 without degradation; TO-220FPAB insulation prevents creepage/clearance violations on dense control boards.

Use Scenario: Remote-controlled start/stop of 3-phase pump motor auxiliary circuits in water treatment plants with high EMI and humidity exposure.

IC Role / Device Role / Timing Role: Isolated mains interface for PLC output modules; provides galvanic separation between control logic and 230 V AC load.

Use Value: UL-certified 2000 V_RMS insulation replaces opto-triac + discrete triac combos; reduces footprint by 40% and improves long-term creepage stability.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
ACST830-8T	Same die, TO-220AB package: non-insulated tab, R_th(j-c) = 2.0 °C/W, no UL insulation rating.	Requires insulating pad/heatsink isolation; suitable only for PCB-mounted designs with full creepage clearance.	Select when higher thermal efficiency is prioritized and system-level isolation is already implemented.
ACST830-8GTR	Same die, D²PAK package: surface-mount, R_th(j-a) = 45 °C/W (1 cm² copper), lead-free RoHS-compliant.	Designed for automated assembly; lower power density than TO-220FPAB; requires larger copper area for thermal management.	Select for high-volume SMT production where reflow compatibility and board space constraints outweigh insulation needs.

Compared with ACST830-8T and ACST830-8GTR, the ACST830-8FP uniquely combines UL-certified 2000 V_RMS insulation, 3.6 °C/W thermal resistance, and through-hole mounting-making it the only choice for cost-sensitive, safety-critical, thermally demanding Class I appliance designs requiring no external isolation.

Availability

ACST830-8FP is available at Aetrix Electronics and suitable for washing machine motor control, refrigerator compressor drive, and HVAC fan switching requiring stable component supply, long-lifecycle support, and certified insulation performance.

Supply support for ACST830-8FP 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 ACST8 series belongs to ST's ACS/ACST power switch family built on Application-Specific Discrete (A.S.D.) technology, engineered specifically for reliable, snubberless AC motor control in home appliances and industrial equipment.

FAQ

What is the maximum surge current the ACST830-8FP can withstand?

The ACST830-8FP supports non-repetitive surge peak on-state current of 80 A at 50 Hz (20 ms) and 84 A at 60 Hz (16.7 ms), verified per IEC 61000-4-5 test conditions with 2 kV line surge. Its crowbar action limits voltage while allowing controlled conduction through the load during transient events.

Does ACST830-8FP require a heatsink for 8 A continuous operation?

Yes-a heatsink is required. At 8 A RMS and T_c = 91 °C, junction temperature remains within spec (T_j ≤ 125 °C) only with R_th(j-c) = 3.6 °C/W and adequate heatsink thermal resistance. Without forced air, a minimum 15 cm² aluminum heatsink is recommended for ambient temperatures up to 43 °C.

Can ACST830-8FP replace a standard triac like BT139-800 in existing designs?

Yes, with qualification. Pin-compatible in TO-220FPAB footprint, but ACST830-8FP offers superior dV/dt immunity (>2000 V/µs vs. ~100 V/µs), integrated overvoltage clamping, and UL insulation-requiring no layout changes but delivering enhanced reliability in motor drive applications.

What is the gate trigger voltage threshold for ACST830-8FP?

The maximum gate trigger voltage (V_GT) is 1.0 V under standard test conditions (V_OUT = 12 V, R_L = 33 Ω), ensuring compatibility with 3.3 V and 5 V microcontrollers without level-shifting. Minimum V_GT is 0.2 V at T_j = 125 °C, guaranteeing robust turn-on across full temperature range.

ACST830-8FP Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: ACS™/A.S.D®

Package/Case:: TO-220-3 Full Pack

Packaging:: Tube

Product Status:: Active

Triac Type:: Standard

Voltage - Off State:: 800 V

Current - On State (It (RMS)) (Max):: 8 A

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

Current - Non Rep. Surge 50, 60Hz (Itsm):: 80A, 84A

Current - Gate Trigger (Igt) (Max):: 30 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-220FP

ACST830-8FP FAQ

1.How can I place an order for ACST830-8FP through Aetrix?

Please submit a Request for Quotation (RFQ) for ACST830-8FP 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 ACST830-8FP reliable?

The price and inventory of ACST830-8FP are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for ACST830-8FP is usually 5 days.

3.What payment methods are accepted for ACST830-8FP?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for ACST830-8FP transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for ACST830-8FP?

ACST830-8FP orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your ACST830-8FP 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 ACST830-8FP?

For technical support, including ACST830-8FP datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your ACST830-8FP requirements.

6.How does Aetrix verify that ACST830-8FP is sourced from the original manufacturer or authorized distributors?

All ACST830-8FP 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 ACST830-8FP meets industry standards.

7.What is the process for return or replacement of ACST830-8FP?

All ACST830-8FP units undergo pre-shipment inspection (PSI). If there is an issue with ACST830-8FP, 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 ACST830-8FP part is unused and in its original packaging.

Return procedure for ACST830-8FP:

1.Submit a request within 90 days.

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

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