STMicroelectronics TXDV1212RG

Overview

TXDV1212RG from STMicroelectronics is a 12 A, 1200 V insulated high-voltage alternistor triac in TO-220AB package, designed for robust three-phase AC power control of inductive and resistive loads. It delivers 170 A non-repetitive surge current (tp = 2.5 ms), 42.5 A/ms critical commutation rate at 10 V/µs, and 2 kV/µs noise immunity-enabling reliable motor starter and heating system switching in industrial grid-connected equipment.

For engineers reviewing the TXDV1212RG datasheet, TXDV1212RG pinout, TXDV1212RG application, or TXDV1212RG equivalent, key selection criteria include blocking voltage rating, dI/dt capability, gate trigger current consistency across temperature, insulation voltage compliance (2500 V_RMS, UL E81734), and thermal resistance (R_th(j-c) = 1.9 °C/W at 360° conduction).

Technical Context

This triac employs alternistor technology to achieve high commutation robustness without snubber circuits, supporting phase-angle and zero-crossing control topologies. Its gate structure enables stable triggering across quadrants I, II, and III with ≤100 mA I_GT and ≤1.5 V V_GT at 25 °C.

Thermal design is enabled by low junction-to-case thermal resistance (1.9 °C/W AC) and rated for continuous operation up to T_j = 125 °C. The insulated TO-220AB package provides 2500 V_RMS isolation between main terminals and heatsink-mounting surface, meeting UL recognition E81734.

Key Specifications

Pinout & Package

TO-220AB insulated package with creepage/clearance optimized for industrial isolation requirements; epoxy meets UL94 V0; mounting torque: 0.4–0.6 N·m.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage triac applications.

Compared with BTB12-800CW and Q6012LH5, TXDV1212RG uniquely combines 1200 V blocking, 42.5 A/ms commutation, and UL-recognized 2500 V_RMS insulation-making it the only drop-in solution for certified three-phase motor starters requiring both surge resilience and safety-compliant mounting.

Availability

TXDV1212RG is available at Aetrix Electronics and suitable for industrial motor starters, three-phase heating systems, HVAC fan controllers, and induction motor speed regulators requiring stable component supply across multi-year production cycles.

Supply support for TXDV1212RG 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, delivering innovative solutions across automotive, industrial, power, and sensing domains since 1987.

The TXDVxx12 series belongs to ST's high-reliability power discrete portfolio, engineered specifically for ruggedized three-phase AC power control in harsh industrial environments where surge immunity, thermal stability, and safety certification are mandatory.

FAQ

What is the maximum allowable case temperature for continuous operation?

The TXDV1212RG supports continuous operation with case temperature up to 90 °C at full 12 A RMS current, per Figure 3 in the datasheet. Derating is required above this point: at 100 °C case temperature, maximum sustainable IT(RMS) drops to approximately 9.5 A due to thermal limits at Tj = 125 °C.

Does this triac require a heatsink for 12 A operation?

Yes-a heatsink is mandatory. With R_th(j-c) = 1.9 °C/W (AC), 12 A operation at 50 Hz generates ~23 W of power dissipation (VTM × IT). Without heatsinking, junction temperature would exceed 125 °C within seconds. A typical 2.5 °C/W heatsink plus thermal interface yields safe operation at ambient ≤50 °C.

Can TXDV1212RG be used in zero-crossing switching applications?

Yes-it supports zero-crossing operation, but its gate trigger characteristics (quadrant I/II/III, 100 mA I_GT) require precise timing alignment. For reliable zero-crossing use, pair with a dedicated zero-crossing optocoupler (e.g., MOC3063) and ensure gate pulse width exceeds 2.5 µs (t_gt typ.) to guarantee latching.

Is the TO-220AB insulated package compatible with standard TO-220 mounting hardware?

Yes-the mechanical footprint matches standard TO-220AB, including hole spacing and tab dimensions. However, the insulated version uses a molded plastic barrier between the metal tab and internal die; mounting screws must not compromise this barrier, and torque must stay within 0.4–0.6 N·m to avoid cracking the insulation layer.