Diodes Incorporated B340LB-13

Overview

B340LB-13 from Diodes Incorporated is a 3.0A, 40V low forward voltage Schottky barrier rectifier in SMB package, featuring 0.35V typical V_F at 3.0A, 70A non-repetitive surge rating, and −40°C to +125°C operating range-used in DC/DC converter output rectification and high-efficiency AC-DC secondary-side rectification.

For engineers reviewing the B340LB-13 datasheet, B340LB-13 pinout, B340LB-13 application, or B340LB-13 equivalent, this device is selected for low-loss power conversion where thermal management on alumina substrates and transient robustness under 60Hz line-frequency surges are critical design requirements.

Technical Context

This Schottky rectifier employs guard ring die construction to enhance transient voltage immunity and prevent edge breakdown during reverse-biased transients. Its low 0.35V forward drop at rated current directly reduces conduction loss in high-current, low-voltage outputs.

The device is rated for 3.0A average rectified current at 90°C terminal temperature when mounted on an alumina substrate, with thermal resistance of 25°C/W junction-to-terminal-enabling predictable thermal design without heatsinking in space-constrained converters.

Key Specifications

Pinout & Package

SMB (DO-214AA) surface-mount package with cathode band polarity marking; compact 4.06–4.57 mm × 1.96–2.21 mm footprint, 0.093 g mass, UL 94V-0 molded plastic body.

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 delivers superior conduction efficiency and surge resilience due to its lower forward voltage and higher I_FSM, while maintaining identical footprint compatibility-making it optimal for thermally constrained, high-reliability 3A rectification tasks.

Availability

B340LB-13 is available at Aetrix Electronics and suitable for DC/DC converter output rectification, AC-DC adapter secondary-side rectification, and automotive body control module power supplies requiring stable component supply across production lifecycles.

Supply support for B340LB-13 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, specializing in high-efficiency power management and signal integrity solutions for industrial, computing, and automotive markets.

The B340LB-13 belongs to Diodes' low-V_F Schottky rectifier product line, engineered specifically for high-current, low-voltage secondary-side rectification where thermal performance and transient robustness are prioritized over ultra-low-cost alternatives.

FAQ

What is the maximum allowable junction temperature for continuous operation?

The B340LB-13 has a maximum junction temperature of +125°C. Continuous operation at this limit requires maintaining terminal temperature ≤90°C per the derating curve, achievable via alumina substrate mounting or sufficient copper area on FR4 PCB. Exceeding this temperature risks parametric shift and long-term reliability degradation.

Can B340LB-13 be used in place of B340LA-13 in existing designs?

Yes, B340LB-13 is a direct functional replacement for B340LA-13 with identical electrical specifications, differing only in package: SMB (B340LB) vs. SMA (B340LA). Layout must accommodate the larger SMB footprint (4.06–4.57 mm × 1.96–2.21 mm), and thermal design should account for its slightly higher mass (0.093 g vs. 0.064 g).

Is the B340LB-13 RoHS compliant and halogen-free?

Yes, the standard B340LB-13 uses matte tin lead-free plating and complies with RoHS Directive 2011/65/EU. It is also halogen-free per IEC 61249-2-21, with chlorine and bromine content below 900 ppm each. The "-F" suffix variant (B340LB-13-F) explicitly denotes this compliance in ordering codes.

How does capacitive loading affect the B340LB-13's current rating?

For capacitive loads, the average rectified current rating must be derated by 20% per the datasheet. At 90°C terminal temperature, this reduces usable I_O from 3.0A to 2.4A to prevent excessive peak currents during capacitor charging, which could exceed the 70A I_FSM limit or accelerate wear-out under repeated cycling.