STMicroelectronics FERD40H100STS

Overview

FERD40H100STS from STMicroelectronics is a 100 V, 40 A average forward current field-effect rectifier diode in TO-220AB package, featuring typ. 0.325 V forward voltage at 125 °C and 40 A, stable leakage current up to 125 °C, and optimized thermal resistance (R_th(j-c) = 0.8 °C/W) for high-efficiency AC/DC adapters and battery chargers.

For engineers reviewing the FERD40H100STS datasheet, FERD40H100STS pinout, FERD40H100STS application, or FERD40H100STS equivalent, this device delivers verified low conduction loss, reduced thermal runaway risk via low VF/IR temperature dependency, and ECOPACK®2-compliant packaging for industrial power supply design.

Technical Context

This field-effect rectifier leverages ST's patented silicon process to decouple forward voltage (VF) and reverse leakage (IR) from junction temperature-enabling stable operation at T_j = 125 °C with IR ≤ 24 mA and VF ≤ 0.705 V at 40 A. Its low R_th(j-c) (0.8 °C/W in TO-220AB) supports direct heatsink mounting without forced airflow.

Designed for high-frequency switching topologies, it exhibits low junction capacitance (typ. ~1000 pF at 1 V) and fast recovery behavior implied by pulse-tested VF/IR characterization (tp < 380 µs), making it suitable for resonant LLC and active-clamp flyback converters where reverse recovery loss must be minimized.

Key Specifications

Pinout & Package

Packaged in TO-220AB (lead-free, RoHS-compliant, ECOPACK®2), this 3-terminal device uses standard anode–cathode–tab configuration. The metal tab is electrically connected to the cathode and serves as primary thermal interface.

Key Features

Applications

Availability

FERD40H100STS is available at Aetrix Electronics and suitable for adapter power supplies, gaming console PSUs, and battery chargers requiring stable component supply, long-lifecycle availability, and ECOPACK®2-compliant packaging.

Supply support for FERD40H100STS 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 industrial, automotive, and consumer markets.

The FERD40H100STS belongs to ST's field-effect rectifier (FER) product line-engineered specifically to replace Schottky and fast recovery diodes in high-current, high-temperature AC/DC and DC/DC applications where thermal stability and low VF are critical.

FAQ

Is FERD40H100STS pin-compatible with standard TO-220AB diodes?

Yes-FERD40H100STS uses industry-standard TO-220AB mechanical outline (per DS11576 Table 4) with identical mounting hole spacing, tab dimensions, and lead pitch. It shares the same anode–cathode–tab terminal assignment as common rectifiers like STTH30L06D, enabling drop-in replacement in existing layouts.

What is the maximum recommended heatsink thermal resistance for continuous 40 A operation?

Using R_th(j-c) = 0.8 °C/W and T_j(max) = 175 °C, with 50 °C ambient and 25 °C case rise target, maximum allowable R_th(c-s) + R_th(s-a) is 2.25 °C/W. A typical extruded aluminum heatsink of 12 cm² surface area achieves ~2.0 °C/W in natural convection.

How does FERD40H100STS compare to Schottky diodes in 100 V class?

Unlike 100 V Schottkys-which suffer >10× higher IR above 100 °C-FERD40H100STS maintains IR ≤ 24 mA at 125 °C. Its VF is comparable (0.325 V vs. 0.35–0.45 V), but its superior thermal stability eliminates thermal runaway risk in compact, sealed adapters.

Can FERD40H100STS be used in synchronous rectification circuits?

No-it is a passive unidirectional rectifier and lacks gate control. It replaces MOSFET-based synchronous rectifiers only in topologies where control complexity or cost outweighs the ~2–3% efficiency gain; it is not a drop-in substitute for SR controllers like STSR3.