STMicroelectronics T825T-6I

Overview

T825T-6I from STMicroelectronics is a 4-quadrant standard-trigger, 8 A RMS, 600 V blocking voltage triac in a TO-220AB insulated package, designed for phase-angle and on/off AC line switching in motor control, lighting, and inrush limiting circuits with high commutation robustness and low thermal resistance (2.8 °C/W junction-to-case).

For engineers reviewing the T825T-6I datasheet, T825T-6I pinout, T825T-6I application, or T825T-6I equivalent, this device delivers verified 25 mA gate trigger current (Q4), 100 V/µs dV/dt immunity at 125 °C, and snubberless operation in value-sensitive industrial and appliance designs requiring reliable 8 A AC load control without external snubbers.

Technical Context

The T825T-6I operates as a bidirectional thyristor with full 4-quadrant triggering capability, supporting gate drive in all quadrants - including Q4 (A2 negative, G positive) - enabling flexible control in both half- and full-wave AC topologies. Its Snubberless™ architecture eliminates the need for external RC snubber networks under specified dV/dt and dI/dt stress conditions.

It features high static and dynamic commutation performance (minimum 500 V/µs dV/dt at 125 °C, 50 A/µs critical dI/dt), low on-state voltage (1.60 V max at 11.3 A), and thermal design support via clip-bonded construction yielding Rth(j-c) = 2.8 °C/W - critical for thermally constrained PCB layouts in compact appliances.

Key Specifications

Pinout & Package

Package: TO-220AB insulated (UL-rated 2500 V_rms isolation, RoHS-compliant, epoxy UL94 V0). Dimensions per ST DocID16192 Rev 4 Table 6.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BTA08-600BWRG and MAC8MCY600, the T825T-6I uniquely combines Q4-trigger compatibility, certified 2500 V_rms isolation, and validated snubberless operation - making it optimal for safety-critical, space-constrained, and noise-prone AC control in certified consumer appliances.

Availability

T825T-6I is available at Aetrix Electronics and suitable for motor control in power tools, dimmable lighting systems, inrush current limiting circuits, and overvoltage crowbar protection requiring stable component supply across production lifecycles.

Supply support for T825T-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, digital, and mixed-signal ICs for automotive, industrial, and consumer applications.

The T8T series belongs to ST's high-reliability AC power switching portfolio, engineered specifically for cost-sensitive, thermally constrained, and safety-certified AC load control in white goods, power tools, and lighting - emphasizing snubberless robustness and UL/ECOPACK® compliance.

FAQ

What is the maximum junction temperature for continuous operation?

The T825T-6I has an operating junction temperature range of –40 °C to +125 °C. Continuous operation above 125 °C is not permitted; derating curves in Figure 3 show IT(RMS) reduction above 97 °C case temperature. Thermal design must ensure Tj stays within limits under worst-case ambient and load conditions.

Can the T825T-6I be used without a heatsink?

No - at 8 A RMS, power dissipation exceeds 10 W even with low VT. With Rth(j-a) = 60 °C/W, junction temperature would exceed 125 °C in free air. A heatsink is mandatory; Figure 1 shows maximum power vs. IT(RMS) at TC = 97 °C, confirming thermal interface and heatsink selection are essential.

Is the T825T-6I compatible with zero-crossing optocouplers like MOC3041?

Yes - its 25 mA IGT (Q4) is fully compatible with the 15–25 mA output of standard zero-crossing optocouplers such as MOC3041 and MOC3063. Gate drive timing must respect minimum pulse width (≥10 µs) and avoid exceeding PG(AV) = 1 W average gate power.

Does the "-6I" suffix indicate RoHS compliance and insulation?

Yes - the "-6I" suffix denotes TO-220AB insulated package (2500 V_rms isolation) and RoHS-compliant construction per EU Directive 2002/95/EC. This is confirmed in Table 7 (Ordering Information) and Section 2 ("Package information") of the datasheet, including UL94 V0 epoxy and ECOPACK® grade documentation.