Vishay General Semiconductor - Diodes Division FESB8JT-E3/45

Overview

FESB8JT-E3/45 from Vishay General Semiconductor is an ultrafast plastic rectifier diode in TO-263AB (D²PAK) package, rated for 600 V repetitive peak reverse voltage, 8.0 A average forward current at T_C = 100 °C, and 35 ns reverse recovery time. It delivers low forward voltage drop (1.50 V @ 8.0 A), high surge capability (125 A I_FSM), and operates up to 150 °C junction temperature - optimized for high-frequency switching power supplies and freewheeling applications.

For engineers reviewing the FESB8JT-E3/45 datasheet, FESB8JT-E3/45 pinout, FESB8JT-E3/45 application, or FESB8JT-E3/45 equivalent, this page provides verified electrical parameters, thermal resistance (R_θJC = 2.2 °C/W), RoHS-compliant packaging, and validated alternatives for SMPS, DC-DC converters, and industrial inverters.

Technical Context

The FESB8JT-E3/45 employs a glass passivated silicon junction enabling ultrafast recovery (35 ns) with low switching losses and minimal reverse recovery charge - critical for high-efficiency 100–500 kHz switch-mode topologies. Its TO-263AB thermally enhanced surface-mount package supports direct heatsink mounting via the exposed cathode tab (Pin 2).

Designed for unidirectional conduction, it features low leakage (10 µA @ 25 °C, 500 µA @ 100 °C), 85 pF junction capacitance at 4.0 V / 1 MHz, and meets J-STD-020 MSL Level 1 with 245 °C peak reflow tolerance - confirming suitability for automated SMT assembly without moisture sensitivity concerns.

Key Specifications

Pinout & Package

Package: TO-263AB (D²PAK), surface-mount, thermally enhanced with exposed cathode tab (Pin 2) for direct heatsinking. Matte tin-plated leads, RoHS-compliant, UL 94V-0 epoxy.

Key Features

Applications

Equivalent & Alternatives

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

Compared with FESB8JT-E3/45, STTH8R06DJF trades thermal performance for smaller footprint, while IXYS MUR860E offers equivalent speed and voltage rating in a through-hole form factor - both require layout adaptation but deliver matching 35 ns recovery and 600 V blocking in high-frequency power conversion.

Availability

FESB8JT-E3/45 is available at Aetrix Electronics and suitable for high-frequency switching mode power supplies, DC-DC converters, and industrial inverters requiring stable component supply, RoHS compliance, and consistent thermal performance across production batches.

Supply support for FESB8JT-E3/45 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

Vishay General Semiconductor is a global leader in discrete semiconductors, specializing in diodes, rectifiers, MOSFETs, and optoelectronics with emphasis on reliability, efficiency, and manufacturability.

The FES(F,B)8xT family was engineered specifically for high-efficiency, high-frequency power conversion - targeting SMPS, UPS, solar inverters, and motor drives where ultrafast recovery, low V_F, and thermal robustness are critical.

FAQ

What is the maximum junction temperature rating for the FESB8JT-E3/45?

The FESB8JT-E3/45 has a maximum junction temperature (T_Jmax) of +150 °C, as specified in the Vishay datasheet Document Number 88600. This rating allows reliable operation in demanding industrial and automotive-adjacent environments when mounted with adequate thermal management. The device's R_θJC of 2.2 °C/W enables effective heat transfer from junction to heatsink or PCB copper, helping maintain safe operating temperatures under 8.0 A continuous load.

Is the FESB8JT-E3/45 RoHS compliant and lead-free?

Yes, the FESB8JT-E3/45 is RoHS-compliant per Directive 2011/65/EU and WEEE 2002/96/EC. Its matte tin-plated leads meet J-STD-002 and JESD22-B102 solderability standards, and the epoxy case conforms to UL 94V-0 flammability rating. The "E3" suffix confirms consumer-grade qualification including JESD201 Class 1A whisker testing - no lead content is present in the finish or die attach materials.

What does the "B" in FESB8JT-E3/45 indicate about the package?

The "B" in FESB8JT-E3/45 identifies the TO-263AB (D²PAK) package variant - distinct from "F" (ITO-220AC) and base "FES8JT" (TO-220AC). TO-263AB features a surface-mount outline with an exposed cathode tab (Pin 2) optimized for thermal conduction to PCB copper or external heatsinks. Its dimensions and mounting pad layout are defined in the datasheet's Package Outline Dimensions section on page 4.

How does the 35 ns reverse recovery time of the FESB8JT-E3/45 impact EMI in high-frequency designs?

The 35 ns t_rr of the FESB8JT-E3/45 significantly reduces reverse recovery charge (Q_rr) and associated di/dt-induced voltage spikes during turn-off, directly lowering high-frequency conducted and radiated EMI in 200–500 kHz SMPS. This allows smaller input/output filters and less stringent shielding - verified in Vishay's typical characteristics curves (Fig. 3–4) showing clean switching waveforms under 0.5 A/1.0 A test conditions.

Can the FESB8JT-E3/45 replace the FES8JT-E3/45 in a design?

No - the FESB8JT-E3/45 (TO-263AB) and FES8JT-E3/45 (TO-220AC) differ in package, thermal path, and mounting method. While both share identical electrical ratings (600 V, 8 A, 35 ns), the TO-263AB requires surface-mount layout with thermal pad, whereas TO-220AC uses through-hole mounting and screw-down heatsinking. Direct replacement would necessitate PCB redesign and thermal validation; they are functionally equivalent but not mechanically interchangeable.