STMicroelectronics TYN825RG

Overview

TYN825RG from STMicroelectronics is a standard 25 A, 800 V repetitive peak off-state voltage (VDRM/VRRM) silicon-controlled rectifier (SCR) in an insulated TO-220AB package. It features 40 mA gate trigger current (IGT), 314 A non-repetitive surge peak on-state current (ITSM), and 2500 Vrms insulation rating, designed for AC power control in industrial motor drives and lighting ballasts.

For engineers reviewing the TYN825RG datasheet, TYN825RG pinout, TYN825RG application, or TYN825RG equivalent, key selection criteria include its 800 V blocking capability, 40 mA gate sensitivity, 2.0 °C/W junction-to-case thermal resistance, and UL1557-certified insulation-critical for safety-compliant AC line-switching designs.

Technical Context

The TYN825RG operates as a unidirectional thyristor with gate-triggered latching conduction. Its 1500 V/µs minimum dV/dt rating at 125 °C ensures robust immunity to false triggering in noisy AC mains environments, while the 50 A/µs critical rate of rise of on-state current (dI/dt) supports fast turn-on under high di/dt loads.

Thermal performance is defined by Rth(j-c) = 2.0 °C/W (insulated package) and IT(RMS) = 25 A at Tc = 83 °C, reflecting derating due to insulating barrier. Electrical behavior includes VTM ≤ 1.6 V at 50 A, Vt0 ≤ 0.77 V, and Rd ≤ 14 mΩ at 125 °C-enabling low conduction loss in continuous-duty phase-control circuits.

Key Specifications

Pinout & Package

TYN825RG uses the TO-220AB insulated package (UL1557 certified, 2500 Vrms isolation). The metal tab is electrically isolated from the device terminals and serves solely as a thermal path.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TYN625RG and TYN1225RG, the TYN825RG provides optimal balance of voltage margin (800 V), cost, and thermal performance for universal 230 VAC industrial equipment-avoiding overdesign while ensuring robustness against typical line surges.

Availability

TYN825RG is available at Aetrix Electronics and suitable for industrial motor drives, AC lighting dimmers, resistive heating controllers, and power supply inrush limiters requiring stable component supply across multi-year production cycles.

Supply support for TYN825RG 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 TYN825RG belongs to ST's standard SCR product line, engineered specifically for cost-effective, reliable AC power switching in industrial controls, lighting, and appliance applications where safety-certified insulation and surge resilience are mandatory.

FAQ

What is the maximum allowable case temperature for continuous 25 A RMS operation?

The TYN825RG supports 25 A RMS continuous conduction only up to Tc = 83 °C, as specified in Table 2. This derating versus non-insulated TO-220AB variants (rated at Tc = 100 °C) results from thermal resistance increase due to the insulating barrier. Heatsink design must ensure case temperature remains at or below this limit under worst-case ambient and airflow conditions.

Can the TYN825RG be directly driven by a 3.3 V microcontroller GPIO?

No-its maximum gate trigger current (IGT) is 40 mA, but gate threshold voltage (VGT) is up to 1.3 V at 25 °C. A 3.3 V GPIO alone cannot source sufficient current through typical series resistors to guarantee reliable turn-on across temperature and unit variation. A dedicated gate driver or transistor buffer is required to deliver ≥40 mA into the gate-cathode junction.

Is the insulated tab electrically connected to any internal terminal?

No-the TO-220AB ins package features a fully isolated metal tab. It has no electrical connection to Anode, Cathode, or Gate. The tab serves exclusively as a thermal interface to the heatsink and must be treated as a floating conductive surface unless intentionally grounded via external means compliant with safety standards.

How does the 2500 Vrms insulation rating impact PCB layout and mechanical mounting?

The 2500 Vrms rating mandates minimum creepage and clearance distances between the insulated tab and any nearby conductive elements (e.g., chassis, ground planes, adjacent traces). Mounting screws must use insulating shoulder washers, and PCB cutouts beneath the tab must prevent solder mask bridging. Layout must comply with UL1557 spacing rules-not just IPC-2221-to maintain certification integrity.