Infineon BAS21-03WE6327: Datasheet, Application Circuit, and SOT-323 Package Overview

The Infineon BAS21-03WE6327 is a high-performance switching diode housed in the ultra-small SOT-323 (SC-70) surface-mount package. Designed for high-speed switching applications, this component is a critical part of modern electronic circuits where efficiency, size, and reliability are paramount. This article provides a detailed look into its datasheet specifications, a typical application circuit, and the advantages of its miniature package.

Datasheet Overview and Key Specifications

The BAS21-03WE6327 is part of a series of switching diodes characterized by their very short reverse recovery time. According to its datasheet, this diode is engineered for high-speed switching and offers excellent performance in circuits requiring rapid on/off transitions.

Key electrical characteristics include:

Repetitive Peak Reverse Voltage (VRRM): 250 V

Average Rectified Forward Current (IF(AV)): 200 mA

Forward Voltage (VF): Typically 1 V at IF = 100 mA

Reverse Recovery Time (trr): A remarkably fast 50 ns (maximum)

These specifications make it an ideal choice for applications such as freewheeling diodes in switching power supplies, polarity protection, and high-frequency signal rectification. The low forward voltage and ultra-fast switching speed contribute to higher overall circuit efficiency by minimizing power losses.

Typical Application Circuit

A common use case for the BAS21-03WE6327 is as a freewheeling or flyback diode across an inductive load, such as a relay coil or a small motor. In such a circuit, the diode protects sensitive components like transistors or MOSFETs from voltage spikes generated when the inductive load is suddenly switched off.

How it works:

1. When the driving transistor (e.g., a MOSFET) is switched on, current flows through the inductive load, and the diode is reverse-biased, acting as an open circuit.

2. When the transistor is switched off, the collapsing magnetic field in the inductor induces a reverse voltage spike.

3. The BAS21-03WE6327, placed in parallel with the inductor, becomes forward-biased by this spike, providing a safe path for the current to circulate and dissipate, thereby clamping the voltage and protecting the switching transistor.

This simple yet vital application underscores the diode's role in enhancing system robustness and longevity.

SOT-323 Package Advantages

The SOT-323 package is a defining feature of the BAS21-03WE6327. This package is significantly smaller than the common SOT-23, making it a perfect fit for space-constrained portable and miniaturized electronics. Its compact dimensions (approximately 2.0 x 1.25 x 0.9 mm) allow for high-density PCB layouts. Despite its small size, it offers good power dissipation capabilities for its class and is compatible with standard automated surface-mount technology (SMT) assembly processes, ensuring reliable and cost-effective manufacturing.

ICGOODFIND Summary

The Infineon BAS21-03WE6327 stands out as a highly reliable and efficient solution for high-speed switching needs. Its robust electrical characteristics, including a high reverse voltage and an extremely fast recovery time, are perfectly complemented by the miniature SOT-323 package. This combination of performance and compactness makes it an excellent component choice for designers working on modern, efficient, and space-saving electronic designs, from power management units to RF modules.

Keywords:

1. Switching Diode

2. SOT-323 Package

3. High-Speed Switching

4. Freewheeling Diode

5. Reverse Recovery Time