STMicroelectronics T405-600B-TR

Overview

T405-600B-TR from STMicroelectronics is a 4 A, 600 V three-quadrant logic-level triac in DPAK package, designed for AC phase control in inductive loads with low gate trigger current (5 mA max) and high commutation robustness. It enables compact motor drive circuits in universal motor appliances without snubber networks.

For engineers reviewing the T405-600B-TR datasheet, T405-600B-TR pinout, T405-600B-TR application, or T405-600B-TR equivalent, key selection criteria include IGT ≤ 5 mA, VDRM = 600 V, dV/dt ≥ 20 V/µs at 125 °C, IT(rms) = 4 A, and DPAK thermal resistance Rth(j-c) = 2.6 °C/W - all critical for reliable zero-crossing and phase-angle control in thermally constrained PCB layouts.

Technical Context

This triac uses ST's Snubberless logic-level technology to achieve high commutation performance without external snubbers, supporting direct microcontroller GPIO triggering. Its three-quadrant operation eliminates quadrant IV firing, reducing false triggering in noisy AC environments.

It features guaranteed turn-on at IGT ≤ 5 mA with 12 V gate drive and RL = 30 Ω, and maintains dI/dt ≥ 50 A/µs at Tj = 125 °C under IG = 2×IGT, enabling fast, stable switching in universal motor and solenoid control where load inductance causes voltage transients.

Key Specifications

Pinout & Package

DPAK (TO-252) surface-mount package with isolated tab; thermal pad soldered to copper pour for heat dissipation; lead-free, halogen-free epoxy molding meeting UL94 V0.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BT134-600D and T410-600B-TR, the T405-600B-TR offers the lowest gate drive demand (5 mA) in the smallest thermally efficient SMT package (DPAK), making it optimal for space-constrained, low-power AC control designs where snubber elimination and zero-crossing reliability are mandatory.

Availability

T405-600B-TR is available at Aetrix Electronics and suitable for universal motor control, electrovalve actuation, kitchen appliance power tools, and dishwasher heating element control requiring stable component supply across industrial and consumer OEM programs.

Supply support for T405-600B-TR 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, mixed-signal, power, and microcontroller solutions for automotive, industrial, and consumer markets.

The T4 series triacs are part of ST's power discrete portfolio, engineered specifically for snubberless, logic-level AC phase control in cost-sensitive, thermally constrained home appliance and industrial equipment.

FAQ

What is the maximum junction temperature for continuous operation?

The T405-600B-TR has an operating junction temperature range of –40 °C to +125 °C. For continuous 4 A RMS operation, case temperature must be held ≤110 °C per Table 3, requiring thermal design that limits Rth(j-a) to ≤70 °C/W with adequate PCB copper area per Figure 11.

Can this triac replace a mechanical relay in a 230 VAC, 3 A resistive load?

Yes - with VDRM = 600 V and IT(rms) = 4 A, it supports 230 VAC resistive loads up to 3 A continuously. Its snubberless design and 5 mA IGT enable silent, bounce-free switching, but external transient suppression (e.g., MOV) is still recommended for inductive load surges.

Is the DPAK package lead-free and RoHS-compliant?

Yes - the T405-600B-TR uses a lead-free, halogen-free molding compound meeting UL94 V0 and RoHS Directive 2011/65/EU. ST's ECOPACK® documentation confirms full compliance, including exemption 7a for lead in copper alloy terminals.

Does this triac require a heatsink for 4 A RMS operation at 60 °C ambient?

Not necessarily - with Rth(j-c) = 2.6 °C/W and Rth(c-a) ≈ 40 °C/W achievable via 25 cm² 35 µm copper pour (per Figure 11), total Rth(j-a) ≈ 42.6 °C/W yields ΔT ≈ 170 °C at 4 A, exceeding 125 °C max junction. A minimal 5 cm² copper pad reduces Rth(c-a) to ~65 °C/W, keeping Tj < 125 °C without added heatsink.