SB550-B Schottky Diode Equivalent & Substitute Parts

Part Overview

The SB550-B is a 50V, 5A Schottky rectifier diode manufactured by Diodes Incorporated in DO-201AD axial through-hole packaging. This component is classified as obsolete, necessitating identification of active equivalent and substitute parts for ongoing design requirements and production continuity. The SB550-B serves applications requiring fast recovery Schottky diode performance with moderate current handling capacity in through-hole form factor.

Substiute Parts

SB550-B

Diodes IncorporatedIn Stock: 1075SB550-B Datasheet

Current PartRFQ

SB550-T

Diodes IncorporatedIn Stock: 30146SB550-T Datasheet

Parametric EquivalentRFQ

SB550-E3/54

Vishay General Semiconductor - Diodes DivisionIn Stock: 7682SB550-E3/54 Datasheet

MFR RecommendedRFQ

SR305 A0G

Taiwan Semiconductor CorporationIn Stock: 1103SR305 A0G Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SB550-B is determined by strict adherence to the following electrical and mechanical parameters:

Primary Substitution Criteria:

• Voltage - DC Reverse (Vr) (Max): 50 V (exact match required)
• Current - Average Rectified (Io): 5 A (exact match required for full compatibility)
• Package / Case: DO-201AD, Axial (mechanical compatibility)
• Mounting Type: Through Hole (form factor requirement)
• Technology: Schottky (functional requirement)
• Speed: Fast Recovery ≤ 500ns, > 200mA (Io) (performance requirement)

Acceptable Parameter Variations:

• Voltage - Forward (Vf) (Max) @ If: Variations within ±20 mV at rated current are acceptable
• Current - Reverse Leakage @ Vr: Consistent at 500 µA @ 50 V across all substitutes
• Operating Temperature - Junction: Minimum junction temperature may vary; maximum must not be lower than original specification

Substitute Classification:

Parametric Equivalent (Full Compatibility): SB550-T maintains identical electrical specifications and current rating, differing only in packaging format (Cut Tape) and product status (Active).

Manufacturer Recommended (Full Compatibility): SB550-E3/54 maintains identical voltage and current ratings with marginally improved forward voltage performance (650 mV vs. 670 mV @ 5 A), offering enhanced efficiency.

Functional Substitute (Reduced Current Rating): SR305 A0G provides identical voltage rating and package form but operates at reduced current capacity (3 A vs. 5 A), suitable only for applications not requiring full 5 A current handling.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Full Electrical Compatibility):

SB550-T is the primary equivalent for the obsolete SB550-B. Both components are manufactured by Diodes Incorporated and maintain identical electrical specifications across all critical parameters: 50 V reverse voltage, 5 A average rectified current, 670 mV forward voltage at 5 A, and -65°C to 150°C junction temperature range. SB550-T holds Active product status with ROHS3 compliance and REACH Unaffected designation. The only distinction is packaging format (Cut Tape versus bulk), which does not affect electrical performance or mechanical fit in through-hole applications.

SB550-E3/54, manufactured by Vishay General Semiconductor - Diodes Division, provides an alternative equivalent with marginally superior forward voltage performance (650 mV @ 5 A versus 670 mV @ 5 A). This component maintains all other electrical specifications and mechanical compatibility. SB550-E3/54 is Active status with ROHS3 compliance and REACH Unaffected designation. The reduced forward voltage results in lower power dissipation and improved efficiency in rectification applications.

For Current-Limited Applications:

SR305 A0G, manufactured by Taiwan Semiconductor Corporation, functions as a substitute only in applications where the circuit current requirement does not exceed 3 A. This component maintains the 50 V reverse voltage rating and DO-201AD through-hole package form factor. The reduced current rating (3 A versus 5 A) and slightly elevated forward voltage (700 mV @ 3 A) restrict its use to lower-power rectification circuits. SR305 A0G is Active status with ROHS3 compliance and REACH Unaffected designation. The operating temperature range (-55°C to 150°C) provides a narrower low-temperature specification compared to the original SB550-B.

Compliance Considerations:

All substitute parts maintain ROHS3 compliance and are suitable for applications subject to RoHS directives. SB550-T and SB550-E3/54 carry REACH Unaffected status, while SR305 A0G also carries REACH Unaffected status, indicating no regulatory restrictions on use or supply.

Frequently Asked Questions (FAQ)

Q: Can SB550-T be used as a direct replacement for SB550-B in all applications?

A: Yes. SB550-T maintains identical electrical specifications: 50 V reverse voltage, 5 A average rectified current, 670 mV forward voltage at 5 A, fast recovery speed, and -65°C to 150°C junction temperature range. The only difference is packaging format (Cut Tape versus bulk), which does not affect electrical performance or mechanical compatibility in through-hole circuits.

Q: What is the advantage of SB550-E3/54 over SB550-T?

A: SB550-E3/54 provides improved forward voltage performance at 650 mV @ 5 A compared to 670 mV @ 5 A for both SB550-B and SB550-T. This 20 mV reduction results in lower power dissipation during rectification, improving overall circuit efficiency. All other electrical and mechanical specifications remain identical.

Q: Can SR305 A0G replace SB550-B in all applications?

A: No. SR305 A0G is suitable only for applications where the circuit current requirement does not exceed 3 A. The component maintains the 50 V reverse voltage rating and DO-201AD package form factor but cannot handle the full 5 A current rating of the original SB550-B. Use SR305 A0G only in reduced-current applications.

Q: Are all substitute parts RoHS compliant?

A: Yes. SB550-T, SB550-E3/54, and SR305 A0G all maintain ROHS3 compliance, meeting environmental and regulatory requirements for lead-free manufacturing and restricted substance limitations.

Q: What is the difference between Cut Tape and bulk packaging?

A: Cut Tape (CT) packaging provides components on adhesive tape in individual quantities suitable for automated pick-and-place assembly. Bulk packaging provides loose components in larger quantities. Both formats contain identical components with identical electrical specifications. Selection depends on assembly process requirements and inventory management practices.

Q: Do all substitutes maintain the same operating temperature range?

A: SB550-T and SB550-E3/54 maintain the identical -65°C to 150°C junction temperature range as SB550-B. SR305 A0G operates over a narrower range of -55°C to 150°C, with a higher minimum temperature specification. For applications requiring operation below -55°C, SR305 A0G is not suitable.

Q: Are there any REACH or ECCN restrictions on these substitute parts?

A: SB550-T, SB550-E3/54, and SR305 A0G all carry REACH Unaffected status, indicating no regulatory restrictions on supply or use. All components are classified under ECCN EAR99, consistent with standard commercial diode classifications.