Diodes Incorporated T4M35T600B

Overview

T4M35T600B from Diodes Incorporated is a 4A RMS, 600V bidirectional silicon thyristor (triac) designed for AC power control in phase-angle dimming and motor speed regulation circuits. It operates reliably across quadrants Q1, Q2, and Q3, supports 40A non-repetitive surge current, maintains ≥500 V/µs dv/dt immunity at +125°C, and features low 1.6V peak on-state voltage at ±4A - enabling efficient switching in 50/60Hz mains-powered lighting and appliance controls.

For engineers reviewing the T4M35T600B datasheet, T4M35T600B pinout, T4M35T600B application, or T4M35T600B equivalent, key selection criteria include verified quadrant operation (Q1/Q2/Q3), gate trigger current (35mA max per quadrant), holding current (35mA), thermal derating to 4A RMS at TC = +100°C, and TO-220AB package compatibility with heatsink-mounting requirements.

Technical Context

This triac implements a three-quadrant triggering architecture that excludes Q4 operation, reducing false turn-on susceptibility under noisy AC line conditions. Its high dv/dt immunity (≥500 V/µs at +125°C) and low IGT (35mA) enable robust gate drive design without complex snubbers in resistive and inductive loads.

The device's 6.6 A²s I²t rating and 40A single-cycle surge capability support reliable inrush handling in motor start-up and heater energization. On-state voltage remains ≤1.6V at ±4A, minimizing conduction losses and thermal stress during continuous RMS operation.

Key Specifications

Pinout & Package

Package: TO-220AB molded plastic housing with matte tin-plated leads, UL 94V-0 rated, weight ≈2.0g. Designed for vertical mounting with heatsink interface via tab (Terminal 2).

Key Features

Applications

Equivalent & Alternatives

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

Compared with BTB16-600BW and MAC30406G, the T4M35T600B uniquely balances 4A capacity, full three-quadrant operation, and 500 V/µs dv/dt immunity in a standard TO-220AB - making it optimal for compact, thermally constrained, noise-resilient AC control designs.

Availability

T4M35T600B is available at Aetrix Electronics and suitable for AC lighting dimmers, universal motor controllers, heating element drivers, and appliance power switches requiring stable component supply and RoHS-compliant manufacturing.

Supply support for T4M35T600B 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability power management, signal integrity, and protection solutions for industrial, computing, and consumer markets.

The T4M35T600B belongs to Diodes' high-immunity triac product line, engineered specifically for robust AC mains switching in thermally demanding, EMI-rich environments where consistent quadrant behavior and surge resilience are critical.

FAQ

What is the maximum junction temperature for continuous operation?

The T4M35T600B has a specified operating junction temperature range of –40°C to +125°C. Continuous operation at the full 4.0A RMS rating requires case temperature (TC) not exceeding +100°C, as defined in the datasheet's derating curve - implying heatsink design must maintain TC ≤ +100°C under worst-case ambient and airflow conditions.

Can this triac be used with zero-crossing trigger circuits?

Yes - the T4M35T600B supports zero-crossing triggering, but its three-quadrant architecture (Q1/Q2/Q3) means gate drive polarity must match the instantaneous voltage polarity across MT1–MT2. For true zero-crossing operation, a dedicated driver IC (e.g., MOC302x) with appropriate coupling is recommended to ensure correct quadrant activation and avoid misfiring.

Is the metal tab (Pin 2) electrically isolated?

No - the metal tab is internally connected to Main Terminal 2 (MT2), as confirmed by the pin assignment diagram and TO-220AB mechanical data. This requires electrical isolation (e.g., mica washer or insulating pad) when mounting to a grounded heatsink, unless the circuit design intentionally references MT2 as the system ground or return path.

Does the "(LS)" suffix indicate lead-free and halogen-free compliance?

Yes - the "(LS)" suffix denotes Diodes Incorporated's "Lead-Free, Green" qualification: fully compliant with RoHS 3 (2015/863/EU), containing <900ppm bromine, <900ppm chlorine (<1500ppm total Br+Cl), and <1000ppm antimony compounds, as verified in DS45697 Rev. 7–2.