Taiwan Semiconductor Corporation BAV21WS-G RRG

Overview

BAV21WS-G from Taiwan Semiconductor is a surface-mount fast switching diode rated for 200 mA average rectified current, 200 V repetitive peak reverse voltage, and 625 mW power dissipation in SOD-323 package; it delivers 4 ns reverse recovery time and 2.5 pF junction capacitance at VR = 0 V, used in high-speed signal routing and DC-DC converter flyback clamping.

For engineers reviewing the BAV21WS-G datasheet, BAV21WS-G pinout, BAV21WS-G application, or BAV21WS-G equivalent, key selection criteria include reverse recovery time, VF at 100 mA, VR rating, thermal resistance (RθJA = 200 °C/W), and halogen-free green compound compliance per IEC 61249-2-21.

Technical Context

This diode operates as a general-purpose small-signal switching device with unidirectional conduction, defined by its cathode-band polarity marking and optimized for automatic insertion. Its 4 ns trr enables efficient operation in >1 MHz switching circuits, while the 200 V VRRM supports use in 12–48 V industrial power rails.

The SOD-323 package provides low thermal resistance (RθJA = 200 °C/W) and moisture sensitivity level 1 handling, and the 2.5 pF CJ at 0 V allows minimal capacitive loading in RF-coupled or timing-sensitive paths. Forward voltage is specified at 1.25 V max under 100 mA DC.

Key Specifications

Pinout & Package

SOD-323 small outline plastic package: 2-terminal surface-mount device, 1.25 mm × 2.5 mm footprint, 0.4 mm typical height, moisture sensitivity level 1, cathode indicated by band on case.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fast switching diode applications.

Compared with BAV20WS-G and MMBD2004LT1G, the BAV21WS-G offers superior thermal performance (RθJA = 200 °C/W) and higher reverse voltage margin, making it optimal for space-constrained 24–48 V industrial power supplies requiring long-term reliability at elevated ambient temperatures.

Availability

BAV21WS-G is available at Aetrix Electronics and suitable for high-frequency switching power supplies, industrial sensor interface protection, and automotive body control modules requiring stable component supply and halogen-free compliance.

Supply support for BAV21WS-G 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

Taiwan Semiconductor is a vertically integrated analog and discrete semiconductor manufacturer headquartered in Hsinchu, Taiwan, serving industrial, computing, and automotive markets since 1979.

The Small Signal Product line includes fast switching, general-purpose, and low-leakage diodes engineered for precision timing, signal integrity, and reliable power conversion in compact SMD packages like SOD-323.

FAQ

What is the maximum reverse voltage rating for BAV21WS-G?

The BAV21WS-G has a repetitive peak reverse voltage (VRRM) rating of 200 V, verified per DS_S0000021 Version A15. This rating applies under standard test conditions (TA = 25°C) and defines the maximum sustained reverse bias the diode can block without breakdown. Exceeding this voltage risks irreversible avalanche failure. The BAV21WS-G is therefore suited for 24 V and 48 V industrial systems with appropriate surge margin.

What does the "G" suffix in BAV21WS-G signify?

Per Taiwan Semiconductor documentation, the "G" suffix in BAV21WS-G indicates halogen-free green compound packaging compliant with IEC 61249-2-21. This means the epoxy molding compound contains no chlorine, bromine, or other halogens, meeting RoHS Directive 2011/65/EU requirements. The "G" is part of the official ordering code and appears on the device marking as well as reel packaging labels.

What is the reverse recovery time (trr) of BAV21WS-G and how is it tested?

The BAV21WS-G has a reverse recovery time (trr) of 4 ns, measured under the condition: IF = IR = 30 mA, RL = 100 Ω, and Irr = 0.1 × IR (per Note 3 in DS_S0000021). This value reflects the time required for the diode to transition from forward conduction to full reverse blocking. It is validated using standardized pulse testing and confirms suitability for switching frequencies up to 5 MHz in practical designs.

Is BAV21WS-G compatible with lead-free reflow soldering processes?

Yes, the BAV21WS-G in SOD-323 package is qualified for lead-free reflow soldering per J-STD-020. Its moisture sensitivity level is 1, meaning it may be stored indefinitely at ≤30°C/60% RH without baking prior to assembly. The device withstands peak reflow temperatures up to 260°C for 10 seconds, consistent with industry-standard Pb-free profiles used for consumer and industrial PCBs.

How does the junction capacitance of BAV21WS-G affect high-frequency circuit performance?

The BAV21WS-G exhibits 2.5 pF junction capacitance (CJ) at VR = 0 V and f = 1.0 MHz. This low value minimizes unwanted coupling and phase shift in RF detector circuits, high-speed data line clamps, and clock distribution networks. In practice, it enables clean signal edges in 100+ Mbps digital interfaces and reduces Q-factor degradation in LC tank circuits where the diode is used as a tuning element.