STMicroelectronics BTA10-400CRG

Overview

BTA10-400CRG from STMicroelectronics is a 10 A, 400 V RMS insulated triac in TO-220AB package, designed for AC mains switching in phase-control and ON/OFF applications. It features 3-quadrant Snubberless™ operation, 50 mA gate trigger current (IGT), 1000 V/µs dV/dt immunity at 125 °C, and UL1557-certified 2500 VRMS isolation - used in heating regulators and motor speed controllers with inductive loads.

For engineers reviewing the BTA10-400CRG datasheet, BTA10-400CRG pinout, BTA10-400CRG application, or BTA10-400CRG equivalent, key selection criteria include insulated tab rating, 3Q commutation performance, gate sensitivity (25–50 mA), thermal resistance (Rth(j-c) = 2.4 °C/W), and compatibility with snubberless inductive load driving.

Technical Context

This triac operates in three quadrants (I, II, III) with no gate triggering in quadrant IV, enabling robust commutation on inductive loads without external snubbers. Its internal ceramic insulation provides 2500 VRMS isolation between case and MT1/MT2 terminals, meeting UL1557 (file E81734).

It delivers 10 A RMS on-state current at Tc = 95 °C, supports non-repetitive surge up to 100 A (50 Hz, 20 ms), and maintains dV/dt immunity ≥1000 V/µs at 125 °C - critical for reliable turn-off in motor and transformer-driven circuits.

Key Specifications

Pinout & Package

TO-220AB insulated package with metal tab electrically isolated from MT1/MT2 terminals. Tab serves as heatsink only; not connected to circuit. Mounting screw must be isolated from PCB ground plane.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BTA10-400BW, the CRG variant adds certified insulation at the cost of +0.9 °C/W thermal resistance; versus T1035-6G, it trades SMT compatibility and higher voltage rating for through-hole serviceability and integrated safety isolation.

Availability

BTA10-400CRG is available at Aetrix Electronics and suitable for heating regulation, light dimming, induction motor control, and static relay replacement requiring stable component supply across industrial OEM and appliance manufacturing programs.

Supply support for BTA10-400CRG 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, power, MCU, and sensor solutions for automotive, industrial, and consumer markets.

BTA10-400CRG belongs to ST's high-reliability triac product line, engineered specifically for robust AC mains switching in safety-critical, thermally demanding, and inductive-load applications.

FAQ

What is the maximum allowable case temperature for continuous 10 A operation?

The BTA10-400CRG supports 10 A RMS continuous current at Tc = 95 °C, as specified in Table 1. Exceeding this temperature reduces current capability linearly per Figure 3; at 105 °C case temperature, derated IT(RMS) drops to ~8.5 A. Thermal design must ensure heatsink interface resistance keeps case below 95 °C under worst-case ambient and airflow conditions.

Can BTA10-400CRG replace a standard 4Q triac in existing designs?

No - BTA10-400CRG is a 3-quadrant (Snubberless™) device and does not trigger in quadrant IV. If the original design relies on gate triggering during negative gate-to-MT2 voltage (e.g., certain zero-crossing driver ICs), substitution may cause failure to turn on. Verify gate drive polarity and quadrant compatibility before replacement.

Is the insulated tab rated for functional or reinforced insulation?

The 2500 VRMS isolation rating complies with UL1557 as reinforced insulation, meaning it provides double protection against electric shock - sufficient for primary-to-secondary barrier applications in Class I appliances without additional isolation components. This is confirmed by UL file E81734.

Does the "C" in BTA10-400CRG indicate 25 mA gate trigger current?

Yes - per Figure 15, the "C" suffix denotes 25 mA maximum IGT (quadrants I–III), distinguishing it from "B" (50 mA) and "BW/CW" variants. This low gate sensitivity enables direct drive from 3.3 V or 5 V logic with minimal series resistance, reducing gate driver component count.