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Home > Products > Discrete Semiconductor Products > Thyristors > TRIACs

STMicroelectronics BTA12-400BRG

Name: BTA12-400BRG
Brand: STMicroelectronics
SKU: BTA12-400BRG
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: BTA12-400BRG

Manufacturer:: STMicroelectronics

Category:: TRIACs

Package:: TO-220-3

Datasheet:: BTA12-400BRG.pdf

Description:: TRIAC 400V 12A TO220

Quantity:: RFQ Add To RFQ list

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Inventory:9,200

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Product details

Overview

BTA12-400BRG from STMicroelectronics is a 12 A RMS, 400 V repetitive peak off-state voltage (VDRM/VRRM), glass-passivated triac in TO-220AB insulated package, designed for phase control and static switching of resistive or inductive loads in AC mains applications such as lighting dimmers, motor speed controllers, and solid-state relays.

For engineers reviewing the BTA12-400BRG datasheet, BTA12-400BRG pinout, BTA12-400BRG application, or BTA12-400BRG equivalent, key selection criteria include its 125 A non-repetitive surge current (8.3 ms), 10 A/µs dI/dt rating at 50 Hz, 250 V/µs dV/dt capability at 110 °C, insulated 2500 V_RMS isolation, and gate trigger current ≤50 mA (Quadrant I–III, B-suffix).

Technical Context

The BTA12-400BRG is a four-quadrant, bidirectional thyristor with symmetrical switching characteristics for full-wave AC control. Its glass-passivated PNPN structure ensures stable commutation and high noise immunity, supported by a minimum commutating dV/dt of 5 V/µs and critical dI/dt of 10 A/µs under repetitive 50 Hz conduction.

Thermal design relies on junction-to-case thermal resistance of 2.5 °C/W (DC) and 2.5 °C/W (360°, 50 Hz), enabling 12 A RMS operation up to 90 °C case temperature. Gate drive requires ≤50 mA trigger current (B-suffix) with 1.5 V maximum gate trigger voltage and 40 mA typical holding current.

Key Specifications

Parameter	Value and Actual Design Meaning
VDRM / VRRM	400 V - Maximum repetitive peak blocking voltage in both directions; defines safe AC mains interface up to 230 V_RMS systems with margin.
IT(RMS)	12 A - Continuous RMS on-state current at Tc = 90 °C; sets heatsink sizing baseline for sustained load switching.
ITSM (8.3 ms)	125 A - Non-repetitive surge current handling; supports motor startup inrush or lamp cold-filament surges without latch-up.
dI/dt (repetitive)	10 A/µs - Minimum critical rate of rise for reliable turn-on without false triggering; enables use with inductive loads like fans or transformers.
(dV/dt)c	10 V/µs - Minimum commutating dV/dt at 110 °C; ensures robust turn-off during voltage transients in noisy AC environments.
IGT (max)	50 mA - Maximum gate trigger current required in Quadrants I–III; determines driver transistor or optocoupler output stage sizing.
Rth(j-c)	2.5 °C/W - Junction-to-case thermal resistance under 360° conduction; used to calculate allowable power dissipation vs. heatsink temperature.

Pinout & Package

Package: TO-220AB plastic, insulated (UL E81734 recognized), 2500 V_RMS isolation between case and terminals, 2.3 g weight, 0.8 m·N recommended mounting torque.

Pin/Terminal	Circuit Role	Design Meaning
A1 (MT1)	Main Terminal 1	Reference electrode for gate triggering; connected to load return or neutral side in standard phase-control configurations.
A2 (MT2)	Main Terminal 2	High-side main terminal; carries full load current and interfaces with AC line or hot side of load.
G	Gate	Control input for bidirectional conduction initiation; requires ≥500 mA peak pulse for reliable triggering in all quadrants.

Key Features

Feature	Design Value
High surge current capability	125 A non-repetitive (8.3 ms) - Enables robust handling of inrush currents without degradation or failure.
Insulated TO-220AB package	2500 V_RMS isolation - Eliminates need for additional insulation barriers in safety-critical AC mains interfaces.
High commutation dV/dt	≥10 V/µs at 110 °C - Ensures reliable turn-off under fast voltage transients common in industrial AC environments.
Low gate trigger current	≤50 mA (B-suffix) - Reduces driver power requirements and simplifies optocoupler or microcontroller GPIO interface design.
Thermal stability	Operating junction range −40 to +150 °C - Supports deployment in wide-temperature industrial enclosures and outdoor-rated equipment.

Applications

Lighting Dimmer Control

Motor Speed Regulation

Use Scenario: Phase-angle dimming of incandescent or halogen lamps in residential/commercial fixtures.

IC Role / Device Role / Timing Role: Bidirectional AC switch controlling conduction angle per half-cycle to adjust RMS power delivered to filament.

Use Value: Delivers smooth, flicker-free dimming with 12 A RMS capacity supporting up to 2.7 kW at 230 VAC.

Use Scenario: Variable-speed control of universal or shaded-pole AC motors in fans, pumps, and HVAC actuators.

IC Role / Device Role / Timing Role: Static switch replacing mechanical relays or carbon brushes to enable silent, wear-free speed adjustment.

Use Value: Withstands 125 A surge current during motor startup and maintains stable commutation under inductive back-EMF.

Solid-State Relay (SSR)

Heating Element Control

Use Scenario: Isolated AC load switching in PLC output modules, industrial control panels, and safety interlocks.

IC Role / Device Role / Timing Role: Primary power switching element providing galvanic isolation and zero-crossing–compatible turn-on.

Use Value: 2500 V_RMS insulation meets UL recognition requirements; 12 A rating supports Class 10 SSR designs.

Use Scenario: Precise ON/OFF or phase-fired control of resistive heating elements in ovens, water heaters, and industrial process tanks.

IC Role / Device Role / Timing Role: High-reliability AC power switch managing thermal cycling and steady-state power delivery.

Use Value: Stable 12 A RMS current handling and −40 to +150 °C junction range ensure long life under repeated thermal stress.

Equivalent & Alternatives

The following parts are listed as comparable options for similar triac switching applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
BT139-600	16 A RMS, 600 V VDRM, non-insulated TO-220 package, higher IGT (100 mA)	Requires external insulation for safety-critical mains interfaces; better suited for higher-voltage 277/400 VAC systems	Select when higher blocking voltage or current rating is needed and isolation is implemented externally.
TIC226M	8 A RMS, 400 V VDRM, TO-220 insulated, lower ITSM (100 A), higher Rth(j-c) (3.5 °C/W)	Limited surge and thermal performance; suitable only for low-duty-cycle or low-power loads	Choose only for cost-sensitive, low-stress applications where 12 A and 125 A surge are not required.

Compared with BT139-600 and TIC226M, BTA12-400BRG uniquely balances 12 A RMS current, 400 V blocking, 2500 V_RMS insulation, and 125 A surge in a single TO-220AB package-making it optimal for safety-compliant, medium-power AC control where space, reliability, and regulatory compliance are co-constrained.

Availability

BTA12-400BRG is available at Aetrix Electronics and suitable for lighting dimmer control, motor speed regulation, solid-state relay implementation, and heating element control requiring stable component supply across industrial production cycles.

Supply support for BTA12-400BRG 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, specializing in power discrete devices, analog ICs, microcontrollers, and automotive-grade components.

The BTA/BTB triac family was developed for robust, high-surge AC power control in industrial, appliance, and building automation systems-emphasizing thermal resilience, electrical noise immunity, and safety-certified packaging.

FAQ

What is the maximum allowable case temperature for continuous 12 A RMS operation?

The BTA12-400BRG is rated for 12 A RMS operation at Tc = 90 °C, as specified in the Absolute Ratings table. Exceeding this temperature requires derating per Figure 4 in the datasheet; at 100 °C case temperature, maximum RMS current drops to approximately 10.5 A.

Is a heatsink mandatory for 12 A RMS operation?

Yes-a heatsink is mandatory. With Rth(j-c) = 2.5 °C/W and power dissipation ≈ 1.5 W/A × 12 A ≈ 18 W at full load, junction temperature would exceed 150 °C without thermal management. A heatsink achieving ≤10 °C/W total Rth(j-a) is required to maintain safe operation at 90 °C case temperature.

Can BTA12-400BRG be triggered directly from a microcontroller GPIO?

No-direct GPIO triggering is unsafe and unreliable. The gate requires ≥500 mA peak current for consistent turn-on; a microcontroller GPIO (typically 20 mA) must drive a buffer stage (e.g., MOC3021 optocoupler + 100 Ω series resistor) to meet IGM = 4 A (20 µs pulse) and PG(AV) = 1 W limits.

Does the "R" in BTA12-400BRG indicate RoHS compliance?

Yes-the "R" suffix denotes RoHS-compliant, lead-free termination per STMicroelectronics' standard product marking convention. This part meets EU Directive 2011/65/EU and has been manufactured without lead, mercury, cadmium, hexavalent chromium, PBB, or PBDE since 2006.

BTA12-400BRG Specifications

Product attributes: Attribute value

Manufacturer:: STMicroelectronics

Series:: -

Package/Case:: TO-220-3

Packaging:: Tube

Product Status:: Obsolete

Triac Type:: Standard

Voltage - Off State:: 400 V

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

Voltage - Gate Trigger (Vgt) (Max):: 1.3 V

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

Current - Gate Trigger (Igt) (Max):: 50 mA

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

Configuration:: Single

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

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: TO-220

BTA12-400BRG FAQ

1.How can I place an order for BTA12-400BRG through Aetrix?

Please submit a Request for Quotation (RFQ) for BTA12-400BRG 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 BTA12-400BRG reliable?

The price and inventory of BTA12-400BRG are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for BTA12-400BRG is usually 5 days.

3.What payment methods are accepted for BTA12-400BRG?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for BTA12-400BRG transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for BTA12-400BRG?

BTA12-400BRG orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your BTA12-400BRG 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 BTA12-400BRG?

For technical support, including BTA12-400BRG datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your BTA12-400BRG requirements.

6.How does Aetrix verify that BTA12-400BRG is sourced from the original manufacturer or authorized distributors?

All BTA12-400BRG 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 BTA12-400BRG meets industry standards.

7.What is the process for return or replacement of BTA12-400BRG?

All BTA12-400BRG units undergo pre-shipment inspection (PSI). If there is an issue with BTA12-400BRG, 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 BTA12-400BRG part is unused and in its original packaging.

Return procedure for BTA12-400BRG:

1.Submit a request within 90 days.

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

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