SA8.5C-B Equivalent & Substitute Parts

Part Overview

The SA8.5C-B is a Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for transient overvoltage protection in telecom applications. This component features an 8.5V reverse standoff voltage with a 14.4V clamping voltage and 35.4A peak pulse current capability in a through-hole DO-204AC (DO-15) package format.

The SA8.5C-B carries an obsolete product status. Identifying equivalent substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production requirements for systems utilizing this TVS diode specification.

Substiute Parts

SA8.5C-B

Littelfuse Inc.In Stock: 821SA8.5C-B Datasheet

Current PartRFQ

SA8.5CA

Taiwan Semiconductor CorporationIn Stock: 16110SA8.5CA Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SA8.5C-B are identified based on electrical and mechanical parameter equivalence within the TVS diode category. The substitution logic requires matching the following critical parameters:

• Voltage Rating: Reverse standoff voltage of 8.5V and clamping voltage of 14.4V
• Current Handling: Peak pulse current capability of 35.4A or greater
• Power Dissipation: Peak pulse power rating of 500W
• Package Format: DO-204AC (DO-15) through-hole axial configuration
• Diode Type: Zener-based TVS topology with single bidirectional channel
• Temperature Range: Operating capability within -65°C to 175°C or compatible subset

The SA8.5CA meets these substitution criteria as a direct equivalent part, maintaining electrical performance specifications and mechanical compatibility while offering improved product status and supply availability.

Parameter Comparison

Engineering Selection Recommendations

The SA8.5CA qualifies as a direct substitute for the SA8.5C-B based on the following engineering criteria:

Electrical Equivalence: The SA8.5CA maintains identical voltage specifications (8.5V reverse standoff, 9.44V breakdown minimum, 14.4V clamping maximum) and equivalent power dissipation (500W peak pulse). The peak pulse current rating of 36A exceeds the original 35.4A specification, providing additional margin.

Mechanical Compatibility: Both parts utilize the DO-204AC (DO-15) through-hole axial package format, ensuring direct pin-for-pin compatibility in existing PCB layouts and assembly processes.

Product Status: The SA8.5CA carries an active product status, contrasting with the obsolete designation of the SA8.5C-B. This status ensures ongoing availability, manufacturing support, and supply chain continuity.

Compliance Enhancement: The SA8.5CA meets ROHS3 compliance standards, representing an advancement over the RoHS Compliant designation of the original part. REACH unaffected status is documented for the substitute.

Temperature Operating Range: The SA8.5CA operates across -55°C to 175°C, which encompasses the majority of the original -65°C to 175°C range. Applications requiring operation below -55°C require specific evaluation against system requirements.

Frequently Asked Questions (FAQ)

Q: Can the SA8.5CA be used as a direct replacement for the SA8.5C-B in existing designs?

A: Yes. The SA8.5CA provides electrical and mechanical equivalence across all critical TVS diode parameters: voltage ratings, current handling, power dissipation, and package format. Direct substitution is supported without circuit modification.

Q: What is the significance of the higher peak pulse current rating (36A vs. 35.4A) on the SA8.5CA?

A: The 36A rating on the SA8.5CA exceeds the original 35.4A specification, providing additional transient current handling capability. This represents a performance enhancement and does not create compatibility issues.

Q: Does the narrower operating temperature range of the SA8.5CA (-55°C to 175°C vs. -65°C to 175°C) affect substitution suitability?

A: The SA8.5CA supports operation down to -55°C. Applications requiring operation below -55°C must evaluate system requirements against this specification. For applications within the -55°C to 175°C range, the substitute is fully compatible.

Q: Are there packaging format differences between the SA8.5C-B and SA8.5CA?

A: The SA8.5C-B is supplied in bulk packaging, while the SA8.5CA is supplied in Tape & Reel (TR) format. Both parts use the identical DO-204AC (DO-15) through-hole axial package. Tape & Reel format is standard for automated assembly processes and does not affect component performance or PCB compatibility.

Q: What compliance certifications apply to the SA8.5CA?

A: The SA8.5CA meets ROHS3 compliance standards and carries REACH unaffected status. Both certifications represent current regulatory requirements for electronic components in industrial and telecom applications.

Q: Are there any application differences between the SA8.5C-B and SA8.5CA?

A: The SA8.5C-B is specified for telecom applications, while the SA8.5CA is designated for general purpose applications. The electrical and mechanical specifications support equivalent performance across both application categories.