STMicroelectronics T1635T-8G

Overview

T1635T-8G from STMicroelectronics is a Snubberless™ Triac in D²PAK package, rated for 16 A RMS on-state current and 800 V repetitive peak off-state voltage, with 35 mA gate trigger current and 150 °C maximum junction temperature. It delivers high commutation robustness (dl/dt)_c ≥12 A/ms at 150 °C and static dV/dt ≥1000 V/µs, enabling reliable phase-angle and on/off AC switching in motor control, heating, and crowbar protection circuits without external snubbers.

For engineers reviewing the T1635T-8G datasheet, T1635T-8G pinout, T1635T-8G application, or T1635T-8G equivalent, key selection criteria include verified three-quadrant operation, non-insulated tab thermal performance (R_th(j-c) = 1.15 °C/W), surge capability up to 126 A (16.7 ms), and Ecopack®2 compliance for RoHS/halogen-free designs.

Technical Context

This triac operates across all three quadrants (I, II, III) with symmetrical triggering characteristics-IGT ≤35 mA and VGT ≤1.3 V at 25 °C-and maintains stable latching/holding behavior (IL ≤65 mA, IH ≤45 mA) over –40 to +150 °C. Its gate structure supports low-power drive while sustaining high immunity to false turn-on via dV/dt ≥2000 V/µs at 125 °C.

The device leverages a non-insulated D²PAK metal tab for direct heatsinking, achieving R_th(j-c) = 1.15 °C/W and enabling full 16 A RMS conduction at T_c = 125.9 °C. Its Snubberless™ design eliminates need for RC snubbers when operated within specified (dl/dt)_c and dV/dt limits, reducing BOM count and board space in AC line-switching applications.

Key Specifications

Pinout & Package

D²PAK (TO-263) package with non-insulated metal tab (A2), UL94 V0 flammability rating, Ecopack®2 compliant (RoHS/halogen-free), and 1.6 g unit weight. Tab serves as Anode 2 (A2) and primary thermal path.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BTB16-800CW and T1635H-8G, the T1635T-8G provides superior thermal performance (1.15 °C/W), higher commutation robustness (12 A/ms), and certified snubberless operation-making it optimal for space-constrained, high-reliability AC power control where dynamic load stresses and thermal management are critical.

Availability

T1635T-8G is available at Aetrix Electronics and suitable for motor control, heating systems, and overvoltage crowbar protection requiring stable component supply, long-term lifecycle assurance, and compliance with RoHS/halogen-free manufacturing standards.

Supply support for T1635T-8G 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, MCU, power, and sensing solutions for automotive, industrial, and consumer markets.

The T1635T-8G belongs to ST's Snubberless™ Triac product line, engineered specifically for high-reliability, snubber-free AC power control in thermally demanding and electrically noisy environments.

FAQ

Is the T1635T-8G compatible with zero-crossing trigger circuits?

Yes-the T1635T-8G supports zero-crossing operation in Quadrants I and III, with guaranteed IGT ≤35 mA and VGT ≤1.3 V at 25 °C. Its three-quadrant architecture ensures reliable triggering near line zero crossings, and its high dV/dt immunity (≥1000 V/µs at 150 °C) prevents false turn-on from noise-induced transients during low-voltage gate drive windows.

What is the maximum allowable case temperature for continuous 16 A RMS operation?

The datasheet specifies that 16 A RMS operation is rated at T_c = 125.9 °C. Exceeding this case temperature requires derating per Figure 2; at T_c = 135 °C, maximum IT(RMS) drops to approximately 14.5 A. Thermal design must ensure the D²PAK tab remains at or below 125.9 °C under worst-case ambient and airflow conditions.

Can the T1635T-8G be used without a heatsink in free-air convection?

No-free-air convection limits IT(RMS) to ~3.5 A at 25 °C ambient (per Figure 3). For 16 A operation, a heatsink is mandatory. The non-insulated tab requires direct thermal interface (e.g., thermal pad or paste) to a heatsink; PCB copper area alone is insufficient unless >30 cm² of 35 µm Cu is used (per Figure 13), which is impractical for 16 A loads.

Does the "T" suffix in T1635T-8G indicate a specific reliability grade or qualification level?

No-the "T" denotes enhanced commutation performance: increased (dl/dt)_c and dV/dt capability versus standard variants like T1635H-8G. It is not a JEDEC qualification grade or automotive AEC-Q101 designation. The device meets industrial-grade reliability standards but is not AEC-Q101 qualified; ST recommends separate validation for automotive applications.