STMicroelectronics STTH8T06DI

Overview

STTH8T06DI from STMicroelectronics is a 600 V tandem extra-fast recovery diode in TO-220AC insulated package, featuring two series-connected 300 V diodes with matched thermal and dynamic equilibrium. It delivers typ. 15 ns reverse recovery time (trr), 6 nC QRR at 25 °C, 2.05 V VF at 8 A/150 °C, and 2.8 °C/W junction-to-case thermal resistance-optimized for continuous conduction mode (CCM) PFC boost stages.

For engineers reviewing the STTH8T06DI datasheet, STTH8T06DI pinout, STTH8T06DI application, or STTH8T06DI equivalent, key selection criteria include hard-switching performance in high-voltage AC-DC front-ends, VF/QRR trade-off positioning between ultrafast silicon and SiC Schottky rectifiers, and insulated-package requirements for reinforced isolation in industrial power supplies.

Technical Context

This device implements ST's Turbo 2 600 V technology to minimize switching losses in high-frequency hard-switched topologies. Its tandem architecture ensures static and dynamic voltage balancing across internal diodes, while ceramic insulation enables 2500 V_rms isolation and 7 pF junction capacitance-critical for EMI control and safety compliance in isolated converters.

Designed for CCM PFC operation, it sustains 8 A average forward current at T_c = 100 °C with peak surge capability of 80 A (10 ms sine), and operates up to 175 °C junction temperature. Softness factor (S) ranges from 1.6 at 25 °C to 0.8 at 125 °C, indicating controlled recovery behavior under varying thermal stress.

Key Specifications

Pinout & Package

Package: TO-220AC insulated (plastic body with internal ceramic insulation, UL94 V0 epoxy, 2500 V_rms isolation rating).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-voltage tandem diode applications.

Compared with STTH8R06DJ and MUR860E, STTH8T06DI uniquely combines certified 2500 V_rms isolation, tandem voltage balancing, and sub-20 ns trr-making it the sole option for space-constrained, safety-certified CCM PFC where thermal and electrical symmetry are non-negotiable.

Availability

STTH8T06DI is available at Aetrix Electronics and suitable for industrial AC-DC power supplies, server rectifier modules, and motor drive DC link protection requiring stable component supply and long-term lifecycle assurance.

Supply support for STTH8T06DI 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, microcontroller, power, and sensor solutions for automotive, industrial, and consumer markets.

STTH8T06DI belongs to ST's Turbo 2 high-voltage diode product line, engineered specifically for high-efficiency, high-reliability PFC and output rectification in industrial and telecom power systems where cost-performance balance and safety certification are critical.

FAQ

What is the maximum allowable case temperature for continuous operation?

The STTH8T06DI supports continuous operation with case temperature (T_c) up to 100 °C, as specified in Table 2 for I_F(AV) = 8 A. Exceeding this requires derating per Figure 1; at T_c = 110 °C, average current must be reduced to ≤6.2 A to maintain junction temperature below 175 °C.

Does the insulated package require special mounting torque or thermal interface material?

Yes-the TO-220AC ins package specifies a recommended mounting torque of 0.4–0.6 N·m to ensure consistent thermal contact without cracking the internal ceramic. Standard thermal paste (e.g., Dow Corning TC-5622) is sufficient; no electrically insulating pads are needed due to the built-in 2500 V_rms barrier.

How does softness factor (S) affect system reliability in PFC applications?

Softness factor quantifies recovery waveform abruptness: S ≥ 0.8 at 125 °C indicates gradual current decay, reducing voltage overshoot and EMI generation during MOSFET turn-on. This directly lowers stress on gate drivers and snubbers, extending mean time between failures in high-duty-cycle PFC stages.

Can STTH8T06DI replace SiC Schottky diodes in 600 V PFC designs?

No-it is not a drop-in replacement. While its VF/QRR ratio offers competitive price/performance, it lacks SiC's zero reverse recovery and 175 °C continuous operation capability. Use STTH8T06DI where 15 ns trr and 2.05 V VF meet efficiency targets, but select SiC for >100 kHz operation or >150 °C ambient environments.