SA75C-B Equivalent & Substitute Parts

Part Overview

The SA75C-B is a transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for telecom applications requiring transient protection. This component features a 75V reverse standoff voltage with a 121V maximum clamping voltage and 4.2A peak pulse current rating in a through-hole DO-204AC (DO-15) axial package.

The SA75C-B is classified as obsolete. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production or repair requirements for systems utilizing this component.

Substiute Parts

SA75C-B

Littelfuse Inc.In Stock: 798SA75C-B Datasheet

Current PartRFQ

SA75CA

Taiwan Semiconductor CorporationIn Stock: 910SA75CA Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SA75C-B TVS diode is determined by strict equivalence across the following critical electrical and mechanical parameters:

Electrical Equivalence Criteria:

• Voltage - Reverse Standoff (Typ): 75V
• Voltage - Breakdown (Min): 83.3V
• Voltage - Clamping (Max) @ Ipp: 121V
• Power - Peak Pulse: 500W
• Bidirectional Channels: 1
• Type: Zener

Mechanical Equivalence Criteria:

• Package / Case: DO-204AC (DO-15)
• Mounting Type: Through Hole
• Axial configuration

Acceptable Variation:

• Current - Peak Pulse (10/1000µs): Minimum 4.2A (higher values acceptable)
• Operating Temperature Range: Minimum -55°C to 175°C (wider ranges acceptable)

The SA75CA meets all electrical and mechanical equivalence criteria and qualifies as a direct substitute for the SA75C-B.

Parameter Comparison

Engineering Selection Recommendations

The SA75CA manufactured by Taiwan Semiconductor Corporation is a qualified substitute for the obsolete SA75C-B. Selection of the SA75CA is supported by the following factors:

Electrical Performance: The SA75CA maintains identical voltage specifications (75V standoff, 83.3V breakdown minimum, 121V clamping maximum) and power rating (500W peak pulse). The peak pulse current rating of 4.3A exceeds the SA75C-B requirement of 4.2A, providing equivalent or superior performance in transient suppression applications.

Mechanical Compatibility: Both components utilize the DO-204AC (DO-15) axial through-hole package, ensuring direct pin-for-pin compatibility and identical PCB footprint requirements.

Compliance Status: The SA75CA holds active product status with ROHS3 compliance certification, whereas the SA75C-B is obsolete. The SA75CA also carries REACH Unaffected status, supporting regulatory requirements for new designs and ongoing production.

Operating Temperature: The SA75CA operating range of -55°C to 175°C is narrower than the SA75C-B range of -65°C to 175°C. This difference is acceptable for applications where the lower temperature limit of -55°C meets system requirements.

Availability: The SA75CA is available in active inventory (863 pcs) in Tape & Reel packaging, supporting both prototype and production-volume requirements.

Frequently Asked Questions (FAQ)

Q: Can the SA75CA directly replace the SA75C-B in existing designs?

A: Yes. The SA75CA is electrically and mechanically equivalent to the SA75C-B. Both components share identical voltage ratings (75V standoff, 121V clamping), power dissipation (500W), and package configuration (DO-204AC through-hole axial). No circuit modifications are required.

Q: What is the difference in peak pulse current between these parts?

A: The SA75C-B is rated for 4.2A peak pulse current, while the SA75CA is rated for 4.3A. The higher rating of the SA75CA provides equivalent or superior transient suppression performance and is fully compatible with designs specified for 4.2A.

Q: Does the operating temperature difference affect substitution?

A: The SA75CA operates from -55°C to 175°C, compared to the SA75C-B range of -65°C to 175°C. The SA75CA is suitable for applications where the minimum operating temperature requirement is -55°C or higher. Applications requiring operation below -55°C require alternative components.

Q: Are both parts RoHS compliant?

A: Yes. The SA75C-B is RoHS Compliant, and the SA75CA is ROHS3 Compliant. Both meet current environmental and regulatory requirements. The SA75CA additionally carries REACH Unaffected certification.

Q: What packaging options are available for the SA75CA?

A: The SA75CA is supplied in Tape & Reel (TR) packaging, suitable for automated assembly processes and production volumes. The SA75C-B was supplied in standard packaging. Both use the same DO-204AC component package.

Q: Why is the SA75C-B classified as obsolete?

A: The SA75C-B is no longer manufactured by Littelfuse Inc. and is classified as obsolete. The SA75CA serves as the active equivalent, manufactured by Taiwan Semiconductor Corporation, and is recommended for new designs and ongoing production support.

Q: Are there any application restrictions for the SA75CA?

A: The SA75CA is rated for general-purpose applications, whereas the SA75C-B was specified for telecom applications. The electrical and mechanical specifications of the SA75CA support both telecom and general-purpose transient voltage suppression requirements.