STMicroelectronics T1635H-8G

Overview

T1635H-8G from STMicroelectronics is a 16 A, 800 V RMS-rated snubberless triac in D²PAK package, designed for high-noise immunity AC load switching at up to 150 °C junction temperature. It supports three-quadrant triggering and delivers robust dynamic commutation (dl/dt)_c ≥16 A/ms and static dV/dt ≥2000 V/µs at T_j = 150 °C, enabling reliable control of universal motors, heaters, and inductive loads in home appliances.

For engineers reviewing the T1635H-8G datasheet, T1635H-8G pinout, T1635H-8G application, or T1635H-8G equivalent, key selection criteria include its 1.1 °C/W junction-to-case thermal resistance, 900 V non-repetitive peak off-state voltage, gate trigger current range (5–35 mA), and ECOPACK2-compliant D²PAK packaging for industrial-grade thermal and environmental reliability.

Technical Context

This triac implements ST's Snubberless high-temperature technology, enabling stable operation without external snubbers across full quadrants I, II, and III. Its design targets thermally demanding AC line control where high dV/dt immunity and strong commutation robustness prevent false triggering and premature turn-off during inductive load transients.

The device operates with a threshold voltage (V_TO) ≤0.80 V and dynamic on-state resistance (R_D) ≤23 mΩ at 150 °C, minimizing conduction losses under sustained 16 A RMS loads. Thermal management is optimized via low R_th(j-c) (1.1 °C/W) and UL94-V0 molding compound, supporting compact heatsink designs in space-constrained applications.

Key Specifications

Pinout & Package

The T1635H-8G is housed in a surface-mount D²PAK (TO-263) package with exposed tab for thermal conduction. The package features three terminals: Anode 1 (A1), Anode 2 (A2), and Gate (G). The metal tab is electrically connected to A2 and serves as the primary thermal path to the PCB copper pad.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BTB16-800CW and Q6016LH4, the T1635H-8G uniquely combines 800 V blocking, 150 °C operation, snubberless commutation, and D²PAK thermal efficiency-making it the sole option for compact, high-reliability 230 VAC appliance control where space, temperature, and EMI resilience are co-constrained.

Availability

T1635H-8G is available at Aetrix Electronics and suitable for home appliance control, industrial motor drives, and smart energy management systems requiring stable component supply across multi-year production cycles.

Supply support for T1635H-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, specializing in power management, analog, MEMS, and microcontrollers for industrial, automotive, and consumer markets.

The T1635H-8G belongs to ST's STPOWER Triac family, engineered specifically for high-reliability, snubberless AC switching in thermally constrained and EMI-prone environments such as white goods and building automation.

FAQ

Is the T1635H-8G compatible with zero-crossing trigger circuits?

Yes - the T1635H-8G supports quadrant I and III triggering, which are fully compatible with standard zero-crossing optotriac drivers (e.g., MOC302x, MOC304x). Its 5–35 mA I_GT range ensures reliable turn-on with typical 10–20 mA gate drive pulses synchronized to line zero crossings.

What is the minimum recommended copper area for thermal relief on FR4 PCB?

Per ST's DS13213, a minimum 16.9 mm × 10.3 mm (≈17.4 cm²) copper pad with 35 µm thickness is recommended under the D²PAK tab to achieve R_th(j-a) ≈ 45 °C/W. For higher power density, doubling copper area reduces R_th(j-a) by ~30%, directly improving thermal headroom.

Does the T1635H-8G require a heatsink in all applications?

No - heatsink requirement depends on RMS current, ambient temperature, and PCB copper area. At 8 A RMS with 17.4 cm² copper and 40 °C ambient, junction temperature remains below 100 °C without external heatsink. Above 12 A RMS or in enclosed 70 °C environments, a heatsink is mandatory per Figure 6 in DS13213.

Can the T1635H-8G replace a BT139-600 in an existing design?

Only with validation - the T1635H-8G has higher voltage rating (800 V vs. 600 V), higher current (16 A vs. 16 A RMS but different thermal profile), and D²PAK vs. TO-220 package. Pinout differs (A1/A2/G vs. MT1/MT2/G), and gate drive timing must be re-verified due to higher dV/dt immunity and different latching behavior.