STMicroelectronics STTH1008DTI

Overview

STTH1008DTI from STMicroelectronics is an 800 V tandem hyperfast rectifier diode composed of two 400 V dice in series, housed in an insulated TO-220AC package. It delivers 10 A average forward current, 40 ns reverse recovery time at 25 °C (1 A), and 1.7 V typical forward voltage at 150 °C/10 A, targeting high-efficiency switch-mode power supplies and PFC stages.

For engineers reviewing the STTH1008DTI datasheet, STTH1008DTI pinout, STTH1008DTI application, or STTH1008DTI equivalent, key selection criteria include reverse recovery softness (Sfactor = 0.8), thermal resistance (Rth(j-c) = 2.5 °C/W), surge capability (IFSM = 120 A), and insulated package suitability for high-voltage isolation requirements.

Technical Context

The STTH1008DTI implements a tandem configuration-two monolithic 400 V diodes integrated in series on a single die-to achieve 800 V VRRM while maintaining balanced dynamic and thermal behavior. Internal ceramic insulation ensures electrical isolation between the cathode terminals and heatsink mounting surface.

Its hyperfast switching performance is defined by trr = 40 ns (typ., 25 °C, 1 A) and tfr = 180 ns (25 °C), with soft recovery (Sfactor = 0.8) minimizing EMI and voltage overshoot during turn-off in hard-switched topologies.

Key Specifications

Pinout & Package

STTH1008DTI uses the TO-220AC insulated package: electrically isolated metal tab (cathode connection), with plastic body meeting UL94 V0 flammability rating. Mounting torque: 0.4–0.6 N·m.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage hyperfast rectifier applications.

Compared with MUR1080CT and VS-10ETX08-M3, STTH1008DTI uniquely combines tandem voltage balancing, ceramic insulation, and 0.8 softness factor-making it optimal for reliability-critical, high-isolation, medium-power industrial rectifiers where die matching and EMI control are prioritized over absolute minimum trr or VF.

Availability

STTH1008DTI is available at Aetrix Electronics and suitable for industrial switch-mode power supplies, active PFC front-ends, and uninterruptible power supplies requiring stable component supply and long-term lifecycle support.

Supply support for STTH1008DTI 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 microcontrollers, power devices, sensors, and analog ICs for industrial, automotive, and consumer markets.

The STTH series targets high-efficiency, high-reliability power conversion-specifically engineered for 600–1200 V rectification in demanding industrial and telecom power systems where thermal stability and voltage balance are critical.

FAQ

What is the maximum junction temperature and how does it affect derating?

The STTH1008DTI has a maximum junction temperature (Tj) of 150 °C. At this limit, its average forward current (IF(AV)) must be reduced to 10 A only when case temperature (Tc) is maintained at 85 °C. For every 10 °C increase in Tc above 85 °C, IF(AV) must be linearly derated by approximately 0.15 A to prevent thermal runaway.

Does the insulated TO-220AC tab require a thermal pad or insulator during heatsink mounting?

No-the TO-220AC ins package integrates internal ceramic insulation between the cathode metallization and the metal tab, enabling direct mounting to a grounded heatsink without additional insulators. The tab is rated for >2500 V isolation, eliminating mica or silicone thermal pads unless local safety standards mandate extra creepage distance.

How does the tandem structure improve reliability versus discrete series-connected diodes?

The tandem structure places both 400 V dice on a single silicon substrate with matched process parameters, ensuring identical forward voltage, reverse leakage, and recovery characteristics. This eliminates voltage imbalance risks caused by parameter spread in discrete diodes, preventing premature failure of one device under transient overvoltage or thermal stress.

Can STTH1008DTI replace standard fast recovery diodes in existing 600 V designs?

Yes-its 800 V VRRM exceeds 600 V system requirements, and its 40 ns trr is significantly faster than typical 100–200 ns fast recovery diodes. However, verify that PCB layout accommodates the insulated tab's mounting requirements and that thermal design accounts for its 2.5 °C/W Rth(j-c), which may allow smaller heatsinks than legacy parts.