STMicroelectronics T1235H-6T

Overview

T1235H-6T from STMicroelectronics is a 12 A, 600 V Snubberless™ Triac in TO-220AB package, designed for high-temperature AC mains switching with 150 °C max junction turn-off commutation, 35 mA max gate trigger current (IGT), and 1.4 °C/W junction-to-case thermal resistance. It enables compact motor control in vacuum cleaners and washing machine drum drives.

For engineers reviewing the T1235H-6T datasheet, T1235H-6T pinout, T1235H-6T application, or T1235H-6T equivalent, key selection criteria include dI/dt rating (50 A/µs at 150 °C), snubberless 3-quadrant commutation capability, insulated voltage rating (2500 V_rms for -6I variant), and thermal performance under sustained 12 A RMS load.

Technical Context

This Triac operates as a bidirectional AC switch with gate-controlled conduction in all three quadrants (I, II, III), supporting universal motor phase-angle control without external snubbers. Its internal ceramic pad provides reinforced insulation, and low dynamic resistance (30 mΩ at 150 °C) minimizes conduction losses during high-current switching.

The device sustains 120 A non-repetitive surge current (50 Hz, 20 ms) and maintains stable triggering up to 150 °C junction temperature, with critical dV/dt immunity of 1000 V/µs (at 150 °C) and (dI/dt)_c ≥ 16 A/ms without snubber.

Key Specifications

Pinout & Package

TO-220AB package with isolated mounting tab (non-insulated variant for T1235H-6T); 3-terminal configuration: A1 (MT1), A2 (MT2), G (Gate). Tab is electrically connected to A2.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BTB12-600CW and T1235H-6I, the T1235H-6T delivers optimal balance of high-temperature robustness, regulatory compliance, and mechanical simplicity-making it preferred for cost-constrained, thermally demanding consumer motor controls where A2-to-heatsink conduction is acceptable.

Availability

T1235H-6T is available at Aetrix Electronics and suitable for vacuum cleaner motor control, washing machine drum drive, and industrial fan speed regulation requiring stable component supply across multi-year production cycles.

Supply support for T1235H-6T 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, digital, and mixed-signal ICs for automotive, industrial, and consumer markets.

The T12xxH series belongs to ST's high-temperature Snubberless™ Triac product line, engineered specifically for compact, high-efficiency AC motor control in thermally constrained white goods and power tools.

FAQ

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

The T1235H-6T supports continuous 12 A RMS operation at Tc = 130 °C, as specified in Table 2 of the datasheet. Exceeding this temperature requires derating per Figure 2, where IT(RMS) drops to ~10.5 A at Tc = 140 °C. Thermal design must ensure case temperature remains within this limit under worst-case ambient and airflow conditions.

Can T1235H-6T replace T1250H-6T in existing designs?

Yes, but only if gate drive capability supports up to 50 mA IGT. The T1235H-6T has lower max IGT (35 mA) than T1250H-6T (50 mA), so it may trigger more easily-but gate resistor values and driver strength must be verified. Electrical parameters like VGT, IH, and dV/dt differ slightly; full functional validation is required before substitution.

Is heatsink mounting torque specified for the TO-220AB package?

Yes, the recommended mounting torque for the TO-220AB package is 0.4 to 0.6 N·m, as stated in the Package Information section. Exceeding 0.6 N·m risks cracking the epoxy body or damaging internal wire bonds; torque below 0.4 N·m may compromise thermal contact and raise junction temperature beyond safe limits.

Does T1235H-6T require a snubber circuit for universal motor loads?

No-its Snubberless™ architecture is validated for 3-quadrant commutation without external RC snubbers, even with highly inductive universal motor loads. This is confirmed by test data in Table 3 showing (dI/dt)c ≥ 16 A/ms at 150 °C and dV/dt ≥ 1000 V/µs, eliminating need for snubber components in typical appliance implementations.