SA13 Transient Voltage Suppressor (TVS) Diode - Equivalent & Substitute Parts

Part Overview

The SA13 is a unidirectional Zener-type transient voltage suppressor diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection applications. The device features a 13V reverse standoff voltage with a 22.58V maximum clamping voltage at peak pulse current, housed in a DO-204AC (DO-15) axial through-hole package. The SA13 is classified as obsolete, necessitating identification of equivalent and substitute parts for ongoing design support and procurement.

Substiute Parts

SA13

Littelfuse Inc.In Stock: 891SA13 Datasheet

Current PartRFQ

SA13A

Fairchild SemiconductorIn Stock: 2531SA13A Datasheet

DirectRFQ

P6KE15A

Fairchild SemiconductorIn Stock: 35449P6KE15A Datasheet

MFR RecommendedRFQ

SA13A-AP

Micro Commercial CoIn Stock: 1177SA13A-AP Datasheet

MFR RecommendedRFQ

SA13A-BP

Micro Commercial CoIn Stock: 688SA13A-BP Datasheet

MFR RecommendedRFQ

SA13A-TP

Micro Commercial CoIn Stock: 894SA13A-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SA13 is determined by the following critical parameters:

• Voltage - Reverse Standoff (Typ): Must be 13V to maintain circuit protection thresholds
• Voltage - Clamping (Max) @ Ipp: Must not exceed 22.58V to ensure adequate transient suppression
• Current - Peak Pulse (10/1000µs): Must be ≥23.7A to handle specified surge conditions
• Power - Peak Pulse: Must be ≥500W for thermal performance
• Package / Case: Must be DO-204AC (DO-15) axial for mechanical and electrical compatibility
• Operating Temperature Range: Must support -55°C to 175°C (TJ) minimum
• Type: Must be Zener unidirectional (1 channel)

Parts meeting these criteria are classified as direct substitutes. Parts with enhanced electrical performance (higher current or power ratings) while maintaining voltage parameters are classified as performance-enhanced substitutes.

Parameter Comparison

Engineering Selection Recommendations

Direct Substitutes (Equivalent Performance):

SA13A (Fairchild Semiconductor), SA13A-AP (Micro Commercial Co), SA13A-BP (Micro Commercial Co), and SA13A-TP (Micro Commercial Co) are direct substitutes. These parts maintain identical voltage standoff (13V), clamping voltage (21.5V maximum), and peak pulse current (23.7A) specifications. All are ROHS3 compliant or REACH unaffected. SA13A-AP, SA13A-BP, and SA13A-TP carry active product status, providing long-term availability and supply chain stability compared to the obsolete SA13.

Performance-Enhanced Substitute:

P6KE15A (Fairchild Semiconductor) is a performance-enhanced substitute offering increased peak pulse current (29A) and power dissipation (600W) while maintaining compatible voltage parameters (12.8V standoff, 21.2V clamping). This part is active and ROHS3 compliant. The lower minimum operating temperature (-50°C versus -55°C) should be evaluated against application requirements.

Procurement Priority:

For new designs and ongoing production, SA13A-AP, SA13A-BP, or SA13A-TP are recommended due to active product status and established supply availability. P6KE15A is suitable where enhanced transient handling capability is required within the same voltage class.

Frequently Asked Questions (FAQ)

Q: Can SA13A variants (SA13A-AP, SA13A-BP, SA13A-TP) be used interchangeably?

A: Yes. These three variants are electrically and mechanically identical, differing only in packaging and distribution channels. All maintain 13V standoff voltage, 21.5V clamping voltage, and 23.7A peak pulse current. Selection depends on packaging availability and supplier preference.

Q: Is P6KE15A a direct replacement for SA13?

A: P6KE15A is functionally compatible but not a direct replacement. It provides enhanced performance with 29A peak pulse current and 600W power dissipation versus 23.7A and 500W for SA13. The standoff voltage is slightly lower (12.8V versus 13V). Use P6KE15A only when the enhanced current and power ratings are required or when circuit analysis confirms the 0.2V lower standoff voltage is acceptable.

Q: What is the significance of the voltage clamping difference between SA13 (22.58V) and SA13A (21.5V)?

A: The SA13A provides superior clamping performance, limiting transient voltage to a lower peak. This represents an improvement in transient suppression capability. Both values fall within acceptable ranges for general-purpose protection applications.

Q: Are all substitute parts available in the same DO-204AC (DO-15) package?

A: Yes. All listed substitutes are supplied in DO-15 (DO-204AC) axial through-hole packages, ensuring mechanical compatibility with existing PCB layouts and assembly processes.

Q: What is the impact of product status (Obsolete vs. Active) on part selection?

A: Obsolete parts (SA13, SA13A) face potential supply discontinuation and limited availability. Active parts (SA13A-AP, SA13A-BP, SA13A-TP, P6KE15A) provide assured long-term supply and manufacturing support. For new designs and production continuity, active parts are preferred.

Q: Do all substitutes meet the same environmental and compliance standards?

A: All listed parts are ROHS3 compliant or REACH unaffected, meeting current environmental regulations. Operating temperature ranges are -55°C to 175°C for SA13, SA13A, and MCC variants, and -50°C to 175°C for P6KE15A. Verify the lower limit of P6KE15A against application requirements if operation below -50°C is required.