STMicroelectronics STTH506B

Overview

STTH506B from STMicroelectronics is an ultrafast high-voltage silicon rectifier diode rated for 600 V repetitive peak reverse voltage, 5 A average forward current, and 30 ns maximum reverse recovery time. It employs Turbo 2 technology to minimize conduction and switching losses, and is optimized for use in industrial switch-mode power supplies (SMPS), PFC stages, and auxiliary power rails.

For engineers reviewing the STTH506B datasheet, STTH506B pinout, STTH506B application, or STTH506B equivalent, key selection criteria include reverse recovery time (trr ≤ 30 ns at 25 °C), low thermal resistance (Rth(j-c) = 3.5 °C/W), soft recovery behavior, and DPAK package compatibility with surface-mount thermal management.

Technical Context

The STTH506B is a single-die, planar passivated, epitaxial ultrafast rectifier with controlled minority-carrier lifetime via platinum diffusion. Its dynamic performance is characterized by low Qrr (175 nC), softness factor >1, and dIF/dt-dependent trr ranging from 30 ns to 50 ns - enabling reduced EMI in high-frequency converters.

Thermally, it features a low Rth(j-c) of 3.5 °C/W and operates up to 175 °C junction temperature. The device exhibits VF(typ) = 1.10 V at 5 A and 150 °C, with IR(max) = 130 µA at 150 °C and VR = 600 V - supporting stable operation in high-temperature industrial environments.

Key Specifications

Pinout & Package

DPAK (TO-252) package: single-diode configuration with cathode (pin 2) and anode (pin 1) terminals; thermally enhanced plastic case with exposed metal tab (pin 3) electrically connected to cathode for direct PCB heat sinking.

Key Features

Applications

Equivalent & Alternatives

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

Compared with STTH8R06D, STTH506B offers smaller DPAK footprint and lower system-level EMI due to faster trr, while VS-5EYH06-M3 trades marginally higher losses for broader distributor availability - making STTH506B optimal for space-constrained, high-frequency industrial SMPS.

Availability

STTH506B is available at Aetrix Electronics and suitable for industrial switch-mode power supplies, PFC circuits, and UPS auxiliary rails requiring stable component supply, long-lifecycle support, and ECOPACK®2-compliant packaging.

Supply support for STTH506B 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.

The STTH series belongs to ST's high-voltage power diode product line, engineered specifically for ultrafast switching and low-loss operation in industrial and computing power conversion systems.

FAQ

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

The STTH506B has a maximum junction temperature (Tj) of 175 °C. This rating enables reliable operation in sealed industrial enclosures or high-ambient environments without forced cooling. Operating consistently above 150 °C increases reverse leakage (IR rises to 130 µA at 150 °C), so thermal design must ensure Tj stays within derated limits per Figure 3 in the datasheet.

Is the STTH506B pin-compatible with other DPAK rectifiers?

Yes - STTH506B uses the standard DPAK (TO-252) outline with anode (pin 1), cathode (pin 2), and cathode-connected thermal tab (pin 3). It shares identical mechanical dimensions and footprint with STTH8R06D-TR, VS-5EYH06-M3, and MUR560, enabling direct PCB layout reuse where electrical specs align.

How does the soft recovery characteristic improve system performance?

The STTH506B exhibits a softness factor >1, meaning its reverse recovery current (Irr) decays gradually rather than abruptly. This reduces voltage overshoot across switching devices, lowers EMI generation, and decreases stress on snubber networks - particularly beneficial in high-dI/dt applications like LLC resonant converters and active clamp forward topologies.

What is the recommended PCB layout for thermal management?

For optimal thermal performance, connect the exposed cathode tab (pin 3) to a minimum 250 mm² copper area (2 oz thickness) using ≥4 thermal vias (0.3 mm diameter, spaced ≤2 mm apart) to inner-layer ground or thermal planes. Avoid isolating the tab - it is electrically tied to cathode and must be part of both thermal and circuit return paths.