STMicroelectronics TYN1212RG

Overview

TYN1212RG from STMicroelectronics is a 12 A, 1200 V sensitive-gate silicon-controlled rectifier (SCR) in TO-220AB package, with gate trigger current <15 mA, on-state voltage ≤1.6 V at 24 A, and critical dV/dt ≥200 V/µs at 125 °C - used for AC motor speed control in industrial HVAC blowers.

For engineers reviewing the TYN1212RG datasheet, TYN1212RG pinout, TYN1212RG application, or TYN1212RG equivalent, key selection criteria include repetitive peak voltage rating, gate sensitivity under high junction temperature, thermal resistance (3.8 °C/W), commutated turn-off time (50 µs), and TO-220AB mechanical mounting torque (0.4–0.6 N·m).

Technical Context

The TYN1212RG operates as a phase-controlled AC switch with sensitive gate triggering (IGT ≤15 mA at 12 V, 33 Ω load), enabling direct drive from low-power logic or optocouplers without amplification. Its 1200 V VDRM/VRRM supports mains-connected 480 VAC industrial systems with safety margin.

Thermal design relies on its 3.8 °C/W junction-to-case resistance and TO-220AB copper tab; electrical robustness includes 120 A non-repetitive surge rating (10 ms), 72 A²s I²t fusing value, and 100 A/µs critical dI/dt to prevent false turn-on during fast current transients.

Key Specifications

Pinout & Package

TO-220AB package with isolated metal tab (pin 2), lead-free, UL94 V0 epoxy, recommended mounting torque 0.4–0.6 N·m. Dimensions per ST Doc ID 022532 Rev 1: 15.9 mm × 10.4 mm × 4.6 mm (L × W × H), 3.8 mm pin pitch.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar SCR switching applications.

Compared with BT139-800R and TYN612, the TYN1212RG uniquely balances 1200 V blocking, 12 A RMS, and <15 mA gate sensitivity in TO-220AB - making it optimal for 480 VAC motor controllers requiring minimal gate drive power and robust noise immunity.

Availability

TYN1212RG is available at Aetrix Electronics and suitable for industrial motor control, solid-state relay manufacturing, and heating system design requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for TYN1212RG 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, designing and manufacturing analog, power, MCU, and sensor solutions for industrial, automotive, and consumer markets.

The TYN1212RG belongs to ST's high-voltage SCR product line, engineered specifically for ruggedized AC power control in harsh industrial environments - emphasizing gate sensitivity, thermal reliability, and surge robustness.

FAQ

What is the maximum junction temperature for continuous operation of the TYN1212RG?

The TYN1212RG has an operating junction temperature range of –40 °C to +125 °C. For continuous 12 A RMS operation, case temperature must be maintained ≤80 °C per absolute ratings table, requiring heatsink thermal resistance ≤10.5 °C/W with 3.8 °C/W Rth(j-c) and ambient derating.

Can the TYN1212RG be used in DC circuits?

No - the TYN1212RG is a unidirectional SCR designed for AC phase-control applications. It lacks inherent turn-off capability in DC; forced commutation (e.g., LC snubber or auxiliary switch) is required, which is not supported by its datasheet specifications or thermal design.

Is a heatsink mandatory for TYN1212RG at 12 A RMS?

Yes - at 12 A RMS, conduction loss exceeds 35 W (VTM × IT). With Rth(j-c) = 3.8 °C/W and max Tj = 125 °C, even at 25 °C ambient, junction temperature would exceed 125 °C without heatsinking. A minimum 10.5 °C/W heatsink is required for 80 °C case temperature.

Does the TYN1212RG have built-in overvoltage protection?

No - the TYN1212RG has no integrated overvoltage protection. External RC snubbers or MOVs must be used across anode–cathode to suppress dv/dt-induced false triggering and protect against line transients, especially in inductive load switching.