Diodes Incorporated B340LB-13-F

Overview

B340LB-13-F from Diodes Incorporated is a 3.0A, 40V SMB-packaged Schottky barrier rectifier with a typical forward voltage of 0.35 V at 3.0 A, 70 A non-repetitive surge rating, and 180 pF junction capacitance at 4 V reverse bias-used in DC/DC converter output rectification and low-voltage power supplies.

For engineers reviewing the B340LB-13-F datasheet, B340LB-13-F pinout, B340LB-13-F application, or B340LB-13-F equivalent, key selection criteria include forward voltage drop at rated current, thermal resistance (35 °C/W), peak repetitive reverse voltage (40 V), leakage current at 40 V (2.0 mA), and SMB package compatibility with automated SMT assembly.

Technical Context

This Schottky rectifier employs guard ring die construction to enhance transient robustness and reduce avalanche failure risk during voltage spikes. Its low VF enables high-efficiency operation in 3.3 V and 5 V secondary-side rectification where conduction losses dominate thermal design.

The device operates across –55 °C to +150 °C junction temperature range and exhibits 150 µA leakage at 15 V reverse bias-critical for standby power integrity in always-on systems. Its 35 °C/W junction-to-terminal thermal resistance supports direct PCB copper pad heatsinking without additional thermal vias under 3 A continuous load.

Key Specifications

Pinout & Package

SMB (DO-214AA) surface-mount package with cathode band marking; two-terminal device: anode and cathode. Molded plastic case meets UL 94V-0 flammability rating; matte tin-plated terminals ensure solderability per MIL-STD-202, Method 208.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SS34 and SK34, B340LB-13-F delivers the lowest VF among 40 V/3 A SMB Schottkys-reducing conduction loss by up to 0.14 V at 3 A, which translates to ~0.42 W less heat generation and eliminates need for thermal vias in many 2-layer PCB designs.

Availability

B340LB-13-F is available at Aetrix Electronics and suitable for DC/DC converter output rectification, USB power delivery front-end protection, and low-voltage AC/DC adapters requiring stable component supply and RoHS-compliant sourcing.

Supply support for B340LB-13-F 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design and manufacturing operations across Asia and the Americas.

The B340LB-13-F belongs to Diodes' general-purpose Schottky rectifier product line, engineered for high-efficiency, low-VF power conversion in cost-sensitive consumer, computing, and industrial power supplies.

FAQ

What is the maximum junction temperature for continuous operation?

The B340LB-13-F has a specified junction temperature range of –55 °C to +150 °C. For continuous DC operation at 3.0 A, thermal design must ensure TJ does not exceed 150 °C-achievable with ≥1 cm² 2 oz copper pad and minimal ambient rise, given its 35 °C/W RθJT.

Is this part suitable for reverse polarity protection in 5 V systems?

Yes. With 40 V VRRM and 0.35 V VF at 3 A, the B340LB-13-F provides low-loss forward conduction and blocks reverse voltage up to 40 V. In a 5 V system, it adds <175 mW loss at 0.5 A load-making it ideal for compact reverse-battery protection paths.

How does the guard ring construction improve reliability?

The guard ring die structure distributes electric field gradients at the PN junction edge, suppressing premature avalanche breakdown during voltage transients. This extends operational life under repetitive 70 A surge conditions and improves immunity to ESD-induced latch-up in unregulated input stages.

Can B340LB-13-F replace B340LA-13-F in existing layouts?

No-B340LB-13-F uses the larger SMB (DO-214AA) package versus SMA (DO-214AC) for B340LA-13-F. Pad layout dimensions differ: SMB requires 4.00–4.57 mm length vs. SMA's 4.00–4.60 mm, and terminal spacing differs. Mechanical interference and solder joint reliability would be compromised without PCB revision.