SA17A Transient Voltage Suppressor (TVS) Diode - Equivalent & Substitute Parts

Part Overview

The SA17A is a unidirectional Zener-type transient voltage suppressor diode manufactured by onsemi, housed in a DO-15 (DO-204AC) axial through-hole package. This component is designed for general-purpose transient voltage suppression applications with a 17V reverse standoff voltage and 27.6V maximum clamping voltage at peak pulse current. The SA17A is currently listed as obsolete, making identification of functionally equivalent active alternatives necessary for ongoing design support and procurement.

Substiute Parts

SA17A

onsemiIn Stock: 300367SA17A Datasheet

Current PartRFQ

SA17A-E3/54

Vishay General Semiconductor - Diodes DivisionIn Stock: 845SA17A-E3/54 Datasheet

DirectRFQ

SA17AHE3/54

Vishay General Semiconductor - Diodes DivisionIn Stock: 1029SA17AHE3/54 Datasheet

DirectRFQ

LCE15A

Littelfuse Inc.In Stock: 2372LCE15A Datasheet

SimilarRFQ

LCE18A

Littelfuse Inc.In Stock: 1007LCE18A Datasheet

SimilarRFQ

P5KE17A-AP

Micro Commercial CoIn Stock: 1095P5KE17A-AP Datasheet

SimilarRFQ

P5KE17A-BP

Micro Commercial CoIn Stock: 961P5KE17A-BP Datasheet

SimilarRFQ

P5KE17A-TP

Micro Commercial CoIn Stock: 893P5KE17A-TP Datasheet

SimilarRFQ

SA17A

Taiwan Semiconductor CorporationIn Stock: 300369SA17A Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SA17A is determined by strict equivalence across the following critical parameters:

• Voltage - Reverse Standoff (Typ): 17V
• Voltage - Breakdown (Min): 18.9V
• Voltage - Clamping (Max) @ Ipp: 27.6V (±tolerance)
• Current - Peak Pulse (10/1000µs): 18.1A (±tolerance)
• Power - Peak Pulse: 500W
• Type: Zener, Unidirectional
• Mounting Type: Through Hole
• Package / Case: DO-204AC or DO-15 equivalent

Substitute parts are categorized as follows:

Direct Equivalents (Identical Electrical and Package Specifications):

• SA17A-E3/54 (Vishay General Semiconductor)
• SA17AHE3/54 (Vishay General Semiconductor, automotive-qualified)
• SA17A (Taiwan Semiconductor Corporation)

Functional Equivalents (Matching Electrical Specifications, Different Package Form Factor):

• P5KE17A-AP (Micro Commercial Co)
• P5KE17A-BP (Micro Commercial Co)
• P5KE17A-TP (Micro Commercial Co)

Similar Voltage Class (Voltage Parameters Within Application Range, Different Current Rating):

• LCE18A (Littelfuse Inc., 18V standoff, 51A peak pulse)
• LCE15A (Littelfuse Inc., 15V standoff, 61A peak pulse)

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (Identical Electrical Performance):

SA17A-E3/54 and SA17AHE3/54 from Vishay General Semiconductor are the primary direct equivalents. Both maintain identical voltage and current specifications. SA17AHE3/54 carries AEC-Q101 automotive qualification and ROHS3 compliance, making it suitable for automotive and regulated applications. SA17A-E3/54 is the standard industrial variant. The Taiwan Semiconductor Corporation SA17A variant provides marginally higher peak pulse current (19A vs 18.1A) and clamping voltage (27.7V vs 27.6V), remaining within functional equivalence.

For Applications Tolerating Minor Current Variance:

The P5KE17A series (P5KE17A-AP, P5KE17A-BP, P5KE17A-TP) from Micro Commercial Co maintains identical voltage specifications but with reduced peak pulse current (16.1A vs 18.1A). These are suitable where transient energy levels are lower or where the application margin permits reduced current handling. All three variants are electrically identical; packaging differences (Bulk designations) reflect distribution format only.

For Higher Energy Transient Applications:

LCE18A and LCE15A from Littelfuse Inc. operate in adjacent voltage classes with significantly higher peak pulse current (51A and 61A respectively) and power dissipation (1500W). These are applicable only where the circuit design accommodates the voltage offset (±1V from nominal) and where higher transient energy absorption is required. Package form factor differs (DO-201 vs DO-15).

Frequently Asked Questions (FAQ)

Q: Can SA17A-E3/54 be used as a direct drop-in replacement for the obsolete SA17A?

A: Yes. SA17A-E3/54 maintains identical electrical specifications (17V standoff, 27.6V clamping, 18.1A peak pulse) and is housed in the equivalent DO-204AC (DO-15) axial through-hole package. Physical dimensions and lead spacing are compatible with original SA17A PCB layouts.

Q: What is the difference between SA17A-E3/54 and SA17AHE3/54?

A: Both are electrically identical. SA17AHE3/54 carries AEC-Q101 automotive qualification and is specified for automotive-grade applications. SA17A-E3/54 is the standard industrial variant. Selection depends on application requirements and qualification mandates.

Q: Why do the P5KE17A variants show lower peak pulse current (16.1A vs 18.1A)?

A: The P5KE17A series maintains the same voltage class and clamping characteristics but is rated for lower transient current. This reflects different internal design parameters. Substitution is valid only where circuit transient energy levels are confirmed to remain within the 16.1A specification.

Q: Can LCE18A or LCE15A replace SA17A in any application?

A: LCE18A and LCE15A operate in adjacent voltage classes (18V and 15V standoff respectively) with significantly higher current and power ratings. These are not direct replacements but may be considered only where the circuit design accommodates the voltage offset and where higher transient energy absorption is beneficial. Package form factor (DO-201) differs from SA17A (DO-15).

Q: Are all substitute parts RoHS compliant?

A: SA17A-E3/54, SA17AHE3/54, SA17A (Taiwan Semiconductor), and LCE18A/LCE15A are ROHS3 compliant. The P5KE17A series compliance status is not specified in available documentation.

Q: What is the operating temperature range for SA17A-E3/54?

A: SA17A-E3/54 is rated for -55°C to 175°C junction temperature (TJ), providing extended low-temperature operation compared to the original SA17A specification.