SA11-B Equivalent & Substitute Parts

Part Overview

The SA11-B is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for transient overvoltage protection in telecom applications. This component features an 11V reverse standoff voltage with an 18.2V maximum clamping voltage and 28A peak pulse current capability in a through-hole DO-204AC (DO-15) axial package.

The SA11-B is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain design continuity, ensure component availability, and support ongoing production and repair requirements for systems utilizing this TVS diode specification.

Substiute Parts

SA11-B

Littelfuse Inc.In Stock: 685SA11-B Datasheet

Current PartRFQ

SA11A

Taiwan Semiconductor CorporationIn Stock: 300315SA11A Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SA11-B TVS diode are identified based on electrical and mechanical parameter equivalence. The following criteria determine substitution eligibility:

Electrical Parameters (Must Match):

• Voltage - Reverse Standoff (Typ): 11V
• Voltage - Breakdown (Min): 12.2V
• Voltage - Clamping (Max) @ Ipp: 18.2V
• Current - Peak Pulse (10/1000µs): 28A
• Power - Peak Pulse: 500W
• Type: Zener, Unidirectional

Mechanical Parameters (Must Match):

• Package / Case: DO-204AC (DO-15), Axial
• Mounting Type: Through Hole
• Unidirectional Channels: 1

Compliance Parameters:

• RoHS Status: RoHS Compliant or equivalent
• Moisture Sensitivity Level (MSL): 1 (Unlimited)

Parts meeting all electrical and mechanical parameters are classified as direct equivalents and may be substituted without circuit redesign.

Parameter Comparison

*The SA11A operates over a narrower temperature range (-55°C to 175°C) compared to the SA11-B (-65°C to 175°C). Applications requiring operation below -55°C require evaluation against specific system requirements.

Engineering Selection Recommendations

SA11A (Taiwan Semiconductor Corporation) - Direct Equivalent

The SA11A is a direct electrical and mechanical equivalent to the SA11-B. All critical TVS diode parameters—reverse standoff voltage, breakdown voltage, clamping voltage, peak pulse current, and peak pulse power—are identical. Both components utilize the same DO-204AC (DO-15) axial through-hole package.

The SA11A holds Active product status, ensuring ongoing availability and manufacturing support. The component is ROHS3 Compliant and REACH Unaffected, meeting current environmental and regulatory requirements. Moisture Sensitivity Level remains at MSL 1 (Unlimited), matching the original specification.

The operating temperature range of the SA11A (-55°C to 175°C) encompasses the upper portion of the SA11-B range. Applications operating exclusively within -55°C to 175°C experience no thermal limitation. Systems requiring operation below -55°C must confirm that the narrower temperature range does not conflict with application requirements.

The SA11A is available in Tape & Reel (TR) packaging, suitable for automated assembly processes. Current inventory levels support production requirements.

Frequently Asked Questions (FAQ)

Q: Can the SA11A directly replace the SA11-B in existing designs?

A: Yes. The SA11A meets all electrical and mechanical specifications of the SA11-B. Both components feature identical reverse standoff voltage (11V), breakdown voltage (12.2V), clamping voltage (18.2V), peak pulse current (28A), and package configuration (DO-204AC, DO-15 axial). Direct substitution is permissible without circuit modification.

Q: What is the difference in operating temperature range between these parts?

A: The SA11-B operates from -65°C to 175°C, while the SA11A operates from -55°C to 175°C. The SA11A has a 10°C higher minimum operating temperature. Applications operating exclusively within -55°C to 175°C are unaffected. Applications requiring operation below -55°C must evaluate whether the narrower range presents a constraint.

Q: Are there packaging differences between SA11-B and SA11A?

A: Both components use the DO-204AC (DO-15) axial through-hole package. The SA11A is supplied in Tape & Reel (TR) format, while the SA11-B was supplied in standard packaging. The physical component remains identical; packaging format differs only in presentation for automated assembly.

Q: What is the product status difference, and why does it matter?

A: The SA11-B is classified as Obsolete, indicating discontinued manufacturing and limited availability. The SA11A is Active, ensuring ongoing production, technical support, and supply chain continuity. For new designs and ongoing production, the SA11A provides long-term component availability.

Q: Are both parts RoHS compliant?

A: Yes. The SA11-B is RoHS Compliant. The SA11A is ROHS3 Compliant, representing the current RoHS standard. Both components meet environmental compliance requirements. The SA11A additionally carries REACH Unaffected status, confirming compliance with chemical substance regulations.

Q: Can I use SA11A in applications originally designed for SA11-B?

A: Yes, provided the application does not require operation below -55°C. All electrical characteristics, mechanical dimensions, and package specifications are equivalent. The SA11A is suitable for telecom and general-purpose transient voltage suppression applications.