STMicroelectronics T1235H-6I

Overview

T1235H-6I from STMicroelectronics is a snubberless 12 A, 600 V RMS triac in insulated TO-220AB package, rated for 150 °C junction temperature operation, with 35 mA max gate trigger current (IGT), 1000 V/µs dV/dt immunity at 150 °C, and 16 A/ms critical commutation current (dI/dt)c - designed for high-power universal motor control in vacuum cleaners and washing machine drum drives.

For engineers reviewing the T1235H-6I datasheet, T1235H-6I pinout, T1235H-6I application, or T1235H-6I equivalent, this part delivers verified high-temperature commutation performance, low thermal resistance (Rth(j-c) = 3.3 °C/W), and reinforced 2500 V_rms isolation - key for compact, thermally constrained AC motor drive designs.

Technical Context

This triac operates in all three quadrants without external snubbers, enabling simplified AC phase-control circuits. Its internal ceramic pad provides 2500 V_rms insulation between case and MT1/MT2 terminals, and its low dynamic resistance (R_d = 30 mΩ at 150 °C) ensures minimal conduction loss under sustained load.

The device sustains 120 A non-repetitive surge current (50 Hz, 20 ms) and maintains ≥1000 V/µs off-state dv/dt immunity even at T_j = 150 °C - critical for reliable turn-off in inductive motor loads with fast voltage transients.

Key Specifications

Pinout & Package

TO-220AB Insulated package with electrically isolated metal tab (mounting surface). Tab is internally connected to MT2 terminal and provides 2500 V_rms isolation from PCB ground plane.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BTB12-600CW and Z0103MN, the T1235H-6I uniquely combines 12 A rating, 150 °C operation, snubberless commutation, and integrated 2500 V_rms isolation - making it the only drop-in solution for safety-certified, high-density universal motor drives requiring no external isolation hardware.

Availability

T1235H-6I is available at Aetrix Electronics and suitable for vacuum cleaner motor control, washing machine drum drives, and industrial fan speed regulation requiring stable component supply, long-lifecycle availability, and consistent parametric performance across production batches.

Supply support for T1235H-6I 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 industrial, automotive, and consumer markets.

The T12xxH series belongs to ST's high-temperature, snubberless triac product line - engineered specifically for compact, thermally demanding AC motor control in white goods and power tools where reliability at 150 °C junction temperature is mandatory.

FAQ

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

The T1235H-6I supports 12 A RMS continuous conduction at T_c = 120 °C, as specified in Table 2 (Absolute Maximum Ratings). Exceeding this case temperature requires current derating per Figure 2 in the datasheet; operation above 120 °C risks exceeding the 150 °C maximum junction temperature limit.

Does the insulated TO-220AB package require a thermal pad or insulator when mounted to a heatsink?

No - the TO-220AB Ins package integrates a ceramic isolation layer between the die and metal tab, providing 2500 V_rms electrical isolation. Direct mounting to an electrically grounded heatsink is permitted without additional insulators, provided mechanical torque is maintained within 0.4–0.6 N·m.

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

Yes, with functional trade-offs: T1235H-6I has lower IGT (35 mA max vs. 50 mA), enabling easier gate drive, but slightly lower commutation robustness - (dI/dt)c = 16 A/ms vs. 21 A/ms and dV/dt = 1000 V/µs vs. 1500 V/µs at 150 °C. Verify gate drive strength and load inductance margins before substitution.

Is the 2500 V_rms isolation rating certified to any specific safety standard?

Yes - the isolation is validated per UL 1557 (reinforced insulation) and supports end-equipment compliance with IEC 60335-1 for household appliances. The UL file number E81734 confirms recognition for use in Class I appliances with accessible conductive parts.