SA33A-E3/73 Equivalent & Substitute Parts

Part Overview

The SA33A-E3/73 is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Vishay General Semiconductor - Diodes Division. This through-hole component operates with a 33V reverse standoff voltage and provides 53.3V clamping at peak pulse current, designed for general-purpose transient voltage protection applications. The part is currently active in production with ROHS3 compliance and unlimited moisture sensitivity rating. Substitute parts are necessary when the original part becomes unavailable, when alternative packaging formats are required, or when enhanced performance specifications are needed for specific circuit requirements.

Substiute Parts

SA33A-E3/73

Vishay General Semiconductor - Diodes DivisionIn Stock: 32266SA33A-E3/73 Datasheet

Current PartRFQ

P6KE39A

Taiwan Semiconductor CorporationIn Stock: 18061P6KE39A Datasheet

MFR RecommendedRFQ

SA33A

Fairchild SemiconductorIn Stock: 21325SA33A Datasheet

MFR RecommendedRFQ

SA33A-TP

Micro Commercial CoIn Stock: 3421SA33A-TP Datasheet

MFR RecommendedRFQ

SLD33U-017

LittelfuseIn Stock: 1564SLD33U-017 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the SA33A-E3/73 is determined by the following critical parameters:

Primary Substitution Criteria:

• Unidirectional channel configuration (1 channel required)
• Voltage - Reverse Standoff: 33V nominal
• Voltage - Breakdown (Min): 36.7V minimum
• Voltage - Clamping (Max) @ Ipp: 53.3V maximum
• Mounting Type: Through Hole
• Package compatibility: DO-15 or DO-204AC axial packages

Secondary Compatibility Factors:

• Current - Peak Pulse (10/1000µs): 9.4A minimum
• Power - Peak Pulse: 500W minimum
• RoHS3 compliance required
• Operating temperature range: -55°C to 175°C minimum

Parts meeting these electrical and mechanical parameters are functionally equivalent and can replace the SA33A-E3/73 in circuit applications. Enhanced specifications (higher current or power ratings) are acceptable substitutes provided all minimum requirements are met.

Parameter Comparison

Engineering Selection Recommendations

P6KE39A (Taiwan Semiconductor Corporation) This substitute meets all electrical parameters with enhanced current rating (11.2A vs 9.4A) and power dissipation (600W vs 500W). Product status is active with ROHS3 compliance. The slightly higher clamping voltage (53.9V vs 53.3V) remains within acceptable tolerance for general-purpose TVS applications. Suitable for direct replacement where enhanced transient protection margin is acceptable.

SA33A (Fairchild Semiconductor) This part is electrically identical to the main part with matching voltage and current specifications. However, product status is obsolete, making it unsuitable for new designs or long-term supply chain planning. Use only when existing inventory must be consumed or for legacy system maintenance.

SA33A-TP (Micro Commercial Co) This substitute provides identical electrical specifications with marginally higher peak pulse current (9.6A vs 9.4A). Product status is active with ROHS3 compliance and specified operating temperature range (-55°C to 175°C). Cut tape packaging format differs from the main part's bulk packaging. Suitable for direct replacement in production environments.

SLD33U-017 (Littelfuse) This substitute maintains identical voltage specifications but provides significantly enhanced current handling (95.7A vs 9.4A) and power dissipation (5000W vs 500W). Product status is active with automotive-grade qualification (AEC-Q101) and ROHS3 compliance. Package format is P600 (different from DO-15), requiring PCB layout verification. Suitable for applications requiring higher transient energy absorption or automotive-grade reliability.

Frequently Asked Questions (FAQ)

Q: Can P6KE39A replace SA33A-E3/73 directly? A: Yes. P6KE39A meets all minimum electrical requirements with enhanced performance specifications. The 0.6V higher clamping voltage and increased current/power ratings provide additional protection margin. Verify PCB footprint compatibility with DO-15 package.

Q: Why is SA33A listed as obsolete? A: SA33A is marked obsolete by Fairchild Semiconductor. While electrically equivalent, obsolete parts present supply chain risk. Use active alternatives (P6KE39A, SA33A-TP, or SLD33U-017) for new designs.

Q: What is the difference between SA33A-TP and SA33A-E3/73? A: Both parts are electrically equivalent with 33V standoff and 53.3V clamping. SA33A-TP is supplied in cut tape format versus bulk packaging. SA33A-TP is active status with specified operating temperature range. Both are suitable substitutes.

Q: When should SLD33U-017 be selected over other substitutes? A: SLD33U-017 is selected when circuit design requires higher transient energy absorption (5kW vs 500W) or when automotive-grade qualification (AEC-Q101) is mandatory. The P600 package differs from DO-15, requiring PCB layout verification before implementation.

Q: Are all substitutes ROHS3 compliant? A: Yes. All listed substitutes (P6KE39A, SA33A, SA33A-TP, and SLD33U-017) are ROHS3 compliant, meeting environmental and regulatory requirements equivalent to the main part.

Q: What packaging formats are available? A: SA33A-E3/73, P6KE39A, SA33A, and SA33A-TP use DO-15 axial packages. SLD33U-017 uses P600 package. Verify PCB footprint compatibility before selection.

Q: Can substitutes be mixed in the same production batch? A: Yes, provided all parts meet the circuit's electrical requirements. However, maintaining single-part standardization per PCB design is recommended for supply chain consistency and traceability.