STMicroelectronics STTH506DTI

Overview

STTH506DTI from STMicroelectronics is a tandem 600V hyperfast boost diode composed of two series-connected 300V silicon dice in a single insulated TO-220AC package. It delivers 5 A average forward current, 12 ns typical reverse recovery time at 25°C, and 3.6 A peak reverse recovery current under hard-switching conditions (dIF/dt = −200 A/µs, Tj = 125°C), specifically engineered for continuous-conduction-mode (CCM) power factor correction (PFC) stages.

For engineers reviewing the STTH506DTI datasheet, STTH506DTI pinout, STTH506DTI application, or STTH506DTI equivalent, this diode is selected for high-dIF/dt PFC boost converters where MOSFET loss reduction, thermal coupling to shared heatsinks, and SiC-competitive recovery performance are critical design requirements.

Technical Context

The STTH506DTI implements a thermally balanced tandem die architecture: two identical 300V diodes connected in series with matched static and dynamic characteristics, enabling 600V blocking while maintaining low Qrr (45 nC) and soft recovery (S = 0.4). Its internal ceramic insulation ensures 2500 VRMS isolation between anode/cathode and case, permitting direct mounting on the same heatsink as the associated MOSFET without additional insulation.

Designed for high dIF/dt operation (up to −500 A/µs), it achieves ultrafast trr (12 ns typ.) and low VFP (7 V transient peak) during turn-on, minimizing switching losses and EMI generation in hard-switched CCM PFC. The device's Rth(j–c) of 3.0 °C/W supports high-power density designs with predictable thermal management.

Key Specifications

Pinout & Package

Insulated TO-220AC package with electrically isolated tab (anode/cathode floating relative to case); mechanical mounting via M3 screw (0.8 N·m recommended torque); UL94 V-0 epoxy encapsulation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-dIF/dt boost diode applications.

Compared with STTH8R06DI and DSSK38-06A, the STTH506DTI uniquely balances ultrafast recovery (12 ns), thermal isolation (2500 VRMS), and compact TO-220AC form factor-making it optimal for space-constrained, single-phase CCM PFC where MOSFET loss reduction and heatsink integration are prioritized over raw current rating.

Availability

STTH506DTI is available at Aetrix Electronics and suitable for industrial motor drives, telecom rectifiers, LED drivers, and EV onboard charger input stages requiring stable component supply and long-term manufacturing continuity.

Supply support for STTH506DTI 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, power, microcontroller, and sensor solutions for industrial, automotive, and consumer markets.

The STTH506DTI belongs to ST's TURBOSWITCH "H" family-engineered specifically for high-efficiency, high-frequency boost PFC applications where ultrafast recovery, thermal integration, and MOSFET loss reduction are primary system-level objectives.

FAQ

Is the STTH506DTI pin-compatible with standard TO-220AC diodes?

Yes-the STTH506DTI uses the standard TO-220AC outline with leads spaced per JEDEC TO-220AC mechanical specification (e.g., e = 4.8–5.4 mm, b1 = 0.61–0.88 mm). However, its electrically isolated tab requires verification of PCB clearance to ground planes and adjacent components, unlike non-isolated variants.

What is the maximum recommended dIF/dt for reliable operation?

The STTH506DTI is characterized up to −500 A/µs in application notes and exhibits stable recovery behavior within datasheet limits. For sustained reliability, ST recommends limiting dIF/dt to ≤ −300 A/µs in production designs-verified via oscilloscope measurement of actual circuit waveforms under worst-case line/load conditions.

Can the STTH506DTI be used in discontinuous conduction mode (DCM) PFC?

While functional in DCM, the STTH506DTI is optimized for CCM operation: its low Qrr and soft recovery deliver greatest benefit when reverse recovery occurs every switching cycle. In DCM, where diode current reaches zero before MOSFET turn-on, recovery-related losses are negligible-making lower-cost diodes more appropriate.

Does the 2500 VRMS isolation rating apply to DC or AC stress?

The 2500 VRMS isolation rating is specified for sinusoidal AC voltage applied between case and either terminal for 1 minute per IEC 60747-5-1. For DC applications, the steady-state isolation withstand is approximately 3500 VDC (derived from RMS-to-peak conversion), confirmed by ST's internal type testing and UL94 V-0 epoxy qualification.