SF32-AP General Purpose Rectifier Diode Equivalent & Substitute Parts

Part Overview

The SF32-AP is a general purpose rectifier diode manufactured by Micro Commercial Co, rated for 100V DC reverse voltage and 3A average rectified current in a DO-201AD axial through-hole package. This component is classified as obsolete, making identification of equivalent and substitute parts necessary for ongoing design support, maintenance, and production continuity. The SF32-AP employs standard diode technology with fast recovery characteristics suitable for general rectification applications.

Substiute Parts

SF32-AP

Micro Commercial CoIn Stock: 833SF32-AP Datasheet

Current PartRFQ

UG4B-E3/73

Vishay General Semiconductor - Diodes DivisionIn Stock: 895UG4B-E3/73 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SF32-AP are identified based on electrical and mechanical compatibility within the following criteria:

Mandatory Matching Parameters:

• Voltage - DC Reverse (Vr) (Max): 100 V
• Package / Case: DO-201AD, Axial
• Mounting Type: Through Hole
• Technology: Standard
• Speed Classification: Fast Recovery ≤ 500ns, > 200mA (Io)
• RoHS Status: ROHS3 Compliant

Allowable Parameter Variations:

• Current - Average Rectified (Io): Equal to or greater than 3A
• Voltage - Forward (Vf) (Max) @ If: Equal to or less than 950 mV
• Reverse Recovery Time (trr): Equal to or less than 35 ns
• Current - Reverse Leakage @ Vr: Equal to or less than 5 µA @ 100 V
• Operating Temperature - Junction: Equal to or greater than the specified range

Substitute parts must maintain or exceed the performance characteristics of the SF32-AP to ensure functional compatibility in existing circuit designs.

Parameter Comparison

Engineering Selection Recommendations

The UG4B-E3/73 manufactured by Vishay General Semiconductor - Diodes Division is a direct substitute for the obsolete SF32-AP. Both components share identical voltage ratings, package specifications, and mounting configurations. The UG4B-E3/73 provides enhanced performance characteristics including higher current capacity (4A versus 3A), faster reverse recovery time (30ns versus 35ns), and an extended operating temperature range (-55°C to 150°C versus -55°C to 125°C).

The substitute part maintains ROHS3 compliance and is currently in active production status, ensuring long-term availability and supply chain stability. The lower junction capacitance of the UG4B-E3/73 (20pF versus 100pF) may provide improved high-frequency performance in certain circuit topologies.

Both components are classified under ECCN EAR99 and HTSUS 8541.10.0080, with identical moisture sensitivity levels (MSL 1 - Unlimited), supporting seamless integration into existing procurement and logistics workflows.

Frequently Asked Questions (FAQ)

Q: Can the UG4B-E3/73 be used as a direct replacement for the SF32-AP in existing circuit designs?

A: Yes. The UG4B-E3/73 meets or exceeds all critical electrical parameters of the SF32-AP, including reverse voltage rating (100V), forward voltage drop (950mV), and reverse recovery time (30ns). Both components use identical DO-201AD axial through-hole packaging, enabling direct mechanical and electrical substitution without circuit board modifications.

Q: What are the key differences between the SF32-AP and UG4B-E3/73?

A: The primary differences are current rating (3A versus 4A), reverse recovery time (35ns versus 30ns), junction capacitance (100pF versus 20pF), operating temperature range (-55°C to 125°C versus -55°C to 150°C), and product status (obsolete versus active). The UG4B-E3/73 provides superior performance across all measured parameters.

Q: Are there any package or mounting compatibility concerns?

A: No. Both the SF32-AP and UG4B-E3/73 utilize the DO-201AD axial package with through-hole mounting. Pin spacing, lead diameter, and mechanical dimensions are identical, ensuring compatibility with existing printed circuit board layouts and assembly processes.

Q: Does the substitute part maintain regulatory compliance?

A: Yes. The UG4B-E3/73 is ROHS3 compliant and REACH unaffected, matching the compliance profile of the SF32-AP. Both components carry identical ECCN (EAR99) and HTSUS (8541.10.0080) classifications.

Q: Why is the reverse recovery time faster in the UG4B-E3/73?

A: The UG4B-E3/73 exhibits a reverse recovery time of 30ns compared to the SF32-AP's 35ns. This parameter is provided in the component specifications and reflects the inherent switching characteristics of the Vishay device. Faster reverse recovery may reduce switching losses in high-frequency rectification applications.

Q: What is the significance of the lower junction capacitance in the UG4B-E3/73?

A: The UG4B-E3/73 has a junction capacitance of 20pF at 4V, 1MHz, compared to 100pF for the SF32-AP. Lower capacitance reduces charge storage effects and may improve performance in circuits operating at higher switching frequencies or with stringent transient response requirements.