STMicroelectronics TXN1012RG

Overview

TXN1012RG from STMicroelectronics is a glass-passivated, insulated-case silicon controlled rectifier (SCR) rated for 1000 V repetitive peak off-state voltage (VDRM/VRRM), 12 A RMS on-state current (IT(RMS)) at Tc=80°C, and 125 A non-repetitive surge current (ITSM, tp=8.3 ms), designed for AC power control in industrial motor drives and resistive/inductive line-frequency power supplies up to 400 Hz.

For engineers reviewing the TXN1012RG datasheet, TXN1012RG pinout, TXN1012RG application, or TXN1012RG equivalent, key selection criteria include its 2500 Vrms isolation rating (UL E81734), 100 A/µs dI/dt capability, 1.5 V maximum gate trigger voltage (VGT), and TO-220AB package with insulated mounting base for direct heatsink attachment without additional insulation.

Technical Context

This SCR employs glass passivation for enhanced surface stability and operates in phase-controlled rectification mode with gate-triggered turn-on only; it lacks gate turn-off capability. Its thermal resistance junction-to-case is 3.5 °C/W (TXN series), enabling high-power dissipation when mounted on heatsinks using method C (conduction cooling).

The device features a minimum dV/dt immunity of 200 V/µs at 125°C with gate open, and typical turn-on time (tgt) of 2 µs under standardized test conditions (VD = VDRM, IG = 40 mA, dIG/dt = 0.5 A/µs), supporting reliable triggering in noisy industrial environments.

Key Specifications

Pinout & Package

TXN1012RG uses the TO-220AB plastic package with insulated mounting base (K-type), where the metal tab is electrically isolated from all terminals. Mounting torque must not exceed 1 m·N to avoid internal damage.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TYN1012 and BT151-1000R, TXN1012RG uniquely combines UL-recognized 2500 Vrms isolation, 12 A RMS rating at 80°C case temperature, and 100 A/µs dI/dt-making it optimal for safety-critical, high-surge industrial AC controllers where simplified mechanical integration and noise immunity are essential.

Availability

TXN1012RG is available at Aetrix Electronics and suitable for industrial motor control, AC power supply regulation, resistive heating management, and lighting dimming systems requiring stable component supply and long-term manufacturing continuity.

Supply support for TXN1012RG 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, specializing in power discrete devices, microcontrollers, sensors, and automotive ICs.

The TXN/TYN family was engineered specifically for rugged, high-reliability AC power control in industrial equipment, emphasizing surge resilience, thermal stability, and safety-certified packaging for direct heatsink integration.

FAQ

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

The TXN1012RG supports 12 A RMS continuous conduction at Tc = 80°C, as specified in the Absolute Ratings table. Exceeding this temperature requires derating per Fig.5 in the datasheet; operation above 80°C risks thermal runaway due to reduced holding current margin and increased leakage.

Can TXN1012RG be used in DC circuits?

No-TXN1012RG is a half-controlled thyristor that latches on once triggered and only commutates when main current falls below holding current (IH ≤ 30 mA). It cannot be actively turned off in DC; use in DC requires forced commutation circuitry or a GTO/GTR, which is outside its design scope.

Is a snubber circuit required for reliable operation?

A snubber (RC network across A–K) is recommended when driving inductive loads or in high-dI/dt environments to suppress voltage spikes exceeding VDRM. The device's 200 V/µs dV/dt rating at 125°C provides margin, but real-world stray inductance may necessitate external protection per IEC 61000-4-4 compliance.

What is the gate drive power requirement for reliable triggering?

Peak gate power must not exceed PGM = 10 W (20 µs pulse), with average gate power limited to PG(AV) = 1 W. A typical driver delivers ≥40 mA pulse at ≤1.5 V for ≤2 µs (tgt), achievable with a 12 V source and 270 Ω series resistor-ensuring robust turn-on while staying within IGT and VGT limits.