SS32 Schottky Diode Equivalent & Substitute Parts

Part Overview

The SS32 is an active Schottky rectifier diode manufactured by Taiwan Semiconductor Corporation, rated for 20 V DC reverse voltage and 3 A average rectified current in a surface mount DO-214AB (SMC) package. This component is designed for fast recovery applications requiring switching speeds of 500 nanoseconds or less at currents exceeding 200 mA. The SS32 maintains 19,566 units in current inventory stock and carries ROHS3 compliance certification with unlimited moisture sensitivity level (MSL 1) rating.

Equivalent and substitute parts are identified when alternative diodes share compatible electrical specifications and mechanical packaging, enabling direct replacement in circuit designs without modification to PCB layouts or electrical connections.

Substiute Parts

SS32

Taiwan Semiconductor CorporationIn Stock: 19676SS32 Datasheet

Current PartRFQ

STPS340S

STMicroelectronicsIn Stock: 50815STPS340S Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SS32 Schottky diode are identified based on the following critical parameters that determine functional compatibility:

Mandatory Compatibility Criteria:

• Technology: Schottky rectifier diode
• Mounting Type: Surface Mount
• Package / Case: DO-214AB or SMC equivalent
• Current - Average Rectified (Io): 3 A minimum
• Speed: Fast Recovery ≤ 500 ns at > 200 mA

Allowable Parameter Variations:

• Voltage - DC Reverse (Vr) (Max): Equal to or greater than 20 V
• Voltage - Forward (Vf) (Max) @ If: May exceed 500 mV without functional impact in most applications
• Current - Reverse Leakage @ Vr: May be lower than 500 µA
• Operating Temperature - Junction (Max): May exceed 125°C
• RoHS and MSL compliance: Must maintain ROHS3 and MSL 1 status

The STPS340S from STMicroelectronics qualifies as a substitute part under these criteria, offering higher reverse voltage rating (40 V) and improved reverse leakage characteristics while maintaining identical current capacity, package form factor, and fast recovery speed specification.

Parameter Comparison

Engineering Selection Recommendations

SS32 Selection Criteria: The SS32 remains the primary choice for applications with strict 20 V reverse voltage specifications and designs optimized for the 500 mV forward voltage characteristic. This component is suitable for circuits where forward voltage drop is a critical design parameter and where the 125°C maximum junction temperature meets thermal requirements.

STPS340S Selection Criteria: The STPS340S serves as a substitute when higher reverse voltage margin is required or when lower reverse leakage current improves circuit performance. The 40 V rating provides additional safety margin in 20 V applications. The extended 150°C maximum junction temperature accommodates higher ambient operating conditions. The 630 mV forward voltage drop must be evaluated against circuit power dissipation and voltage regulation requirements.

Both components maintain ROHS3 compliance and MSL 1 certification, ensuring compatibility with standard PCB assembly processes and storage conditions. Selection between these parts depends on application-specific requirements for voltage margin, thermal performance, and forward voltage characteristics rather than regulatory or packaging constraints.

Frequently Asked Questions (FAQ)

Q: Can the STPS340S directly replace the SS32 on existing PCBs without layout modifications?

A: Yes. Both components use identical DO-214AB (SMC) package geometry and pinout configuration. No PCB layout changes are required for physical substitution.

Q: What is the significance of the higher 40 V reverse voltage rating on the STPS340S?

A: The 40 V rating on the STPS340S provides a 2:1 safety margin over the 20 V application requirement. This higher rating does not degrade performance in 20 V circuits but offers protection against transient overvoltage conditions. The component operates safely at voltages below its maximum rating.

Q: How does the 630 mV forward voltage of the STPS340S compare to the 500 mV of the SS32?

A: The STPS340S exhibits 130 mV higher forward voltage drop at 3 A. In power supply and rectification circuits, this increases power dissipation and heat generation. Circuit designers must evaluate whether this additional voltage drop affects regulation, efficiency, or thermal management requirements.

Q: Are there any temperature-related differences between these diodes?

A: The STPS340S supports operation to 150°C maximum junction temperature, compared to 125°C for the SS32. This extended range accommodates applications in higher ambient temperature environments or designs with elevated thermal loads. Both components operate across the full -55°C to 125°C range, making them interchangeable for standard temperature applications.

Q: What does the lower reverse leakage current of the STPS340S indicate?

A: The STPS340S exhibits 20 µA reverse leakage at 40 V compared to 500 µA at 20 V for the SS32. Lower reverse leakage reduces standby power consumption and improves circuit efficiency in applications where the diode blocks reverse voltage for extended periods. This characteristic is particularly beneficial in battery-powered or low-power standby circuits.

Q: Do both diodes meet the same regulatory and compliance standards?

A: Yes. Both the SS32 and STPS340S carry ROHS3 compliance certification and MSL 1 (unlimited) moisture sensitivity rating. They are equivalent from regulatory and assembly process perspectives, with no additional handling or storage requirements for substitution.

Q: What is the fast recovery specification, and why is it identical for both diodes?

A: Fast recovery ≤ 500 ns at currents exceeding 200 mA indicates switching speed capability in high-frequency rectification applications. Both diodes meet this specification, ensuring compatible performance in switching power supplies, inverters, and other fast-switching circuits. The identical specification confirms functional equivalence for speed-critical applications.