SA40C Transient Voltage Suppressor (TVS) Diode - Equivalent & Substitute Parts

Part Overview

The SA40C is a 40V reverse standoff Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose transient protection applications. This component features a DO-204AC (DO-15) axial through-hole package and is classified as obsolete. Due to its obsolete status, equivalent substitute parts from active manufacturers are necessary to maintain design continuity and ensure ongoing component availability for production and repair applications.

Substiute Parts

SA40C

Littelfuse Inc.In Stock: 993SA40C Datasheet

Current PartRFQ

SA40CA

Taiwan Semiconductor CorporationIn Stock: 1417SA40CA Datasheet

DirectRFQ

P5KE40CA-TP

Micro Commercial CoIn Stock: 1216P5KE40CA-TP Datasheet

MFR RecommendedRFQ

P6KE47CA

Diotec SemiconductorIn Stock: 25492P6KE47CA Datasheet

MFR RecommendedRFQ

SA40CA-AP

Micro Commercial CoIn Stock: 981SA40CA-AP Datasheet

MFR RecommendedRFQ

SA40CA-BP

Micro Commercial CoIn Stock: 1019SA40CA-BP Datasheet

MFR RecommendedRFQ

SA40CA-TP

Micro Commercial CoIn Stock: 1074SA40CA-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SA40C is determined by strict electrical and mechanical parameter matching within the TVS diode category. The following criteria establish valid equivalency:

Primary Substitution Criteria:

• Reverse standoff voltage: 40V (±tolerance)
• Breakdown voltage minimum: 42.08V to 44.4V range
• Clamping voltage maximum: 64.5V to 67.73V range
• Peak pulse current: 7.8A to 9.7A
• Power dissipation: 500W to 600W
• Package type: DO-204AC / DO-15 axial through-hole
• Zener type, single bidirectional channel
• Operating temperature range: -50°C to -55°C minimum, 175°C maximum

All substitute parts listed maintain electrical performance within the specified parameter windows and share identical mechanical mounting characteristics, ensuring direct form-fit-function replacement capability.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (Highest Compatibility):

SA40CA-AP, SA40CA-BP, and SA40CA-TP from Micro Commercial Co. are direct functional equivalents with active product status. These parts maintain identical electrical parameters to the original SA40C specification and share the same operating temperature range (-55°C to 175°C). All three variants are REACH compliant and suitable for immediate replacement in existing designs.

SA40CA from Taiwan Semiconductor Corporation is an active-status alternative with marginally improved peak pulse current (8.1A vs. 7.9A) and identical clamping voltage performance. This part carries ROHS3 compliance and REACH unaffected status.

Secondary Substitute (Extended Performance):

P5KE40CA-TP from Micro Commercial Co. provides equivalent electrical performance with an extended lower operating temperature limit (-65°C vs. -55°C), offering enhanced cold-temperature capability. Peak pulse current is 7.8A, within acceptable tolerance of the original specification.

Alternative Substitute (Higher Power Dissipation):

P6KE47CA from Diotec Semiconductor offers increased peak pulse current (9.7A) and power dissipation (600W vs. 500W), providing margin for applications requiring higher transient energy absorption. Operating temperature minimum is -50°C. This part is ROHS3 compliant.

All substitute parts maintain DO-204AC / DO-15 axial through-hole packaging, ensuring mechanical compatibility without PCB redesign.

Frequently Asked Questions (FAQ)

Q: Can SA40CA-AP, SA40CA-BP, and SA40CA-TP be used interchangeably with SA40C?

A: Yes. These three Micro Commercial Co. variants are direct functional equivalents with identical electrical specifications and operating temperature ranges. The suffix designations (AP, BP, TP) indicate packaging or tape configuration variants but do not affect electrical performance or mechanical compatibility.

Q: What is the difference between the substitute parts listed?

A: All substitute parts meet the 40V reverse standoff requirement and maintain clamping voltage performance within 64.5V to 67.73V. Primary differences are: peak pulse current ranges from 7.8A to 9.7A, power dissipation from 500W to 600W, and operating temperature minimums from -50°C to -65°C. Selection depends on application thermal and transient energy requirements.

Q: Is the P6KE47CA suitable as a direct replacement?

A: P6KE47CA is electrically compatible within the specified parameter window. It provides higher peak pulse current (9.7A) and power dissipation (600W), making it suitable for applications requiring enhanced transient protection margin. Operating temperature minimum is -50°C, which may be a constraint in extreme cold environments.

Q: Are all substitute parts RoHS compliant?

A: SA40CA, P6KE47CA, SA40CA-AP, SA40CA-BP, and SA40CA-TP are confirmed ROHS3 compliant. Compliance documentation should be verified with the specific supplier for the exact manufacturing lot.

Q: Can I use P5KE40CA-TP in applications requiring -55°C operation?

A: P5KE40CA-TP has an extended lower operating temperature limit of -65°C, which exceeds the -55°C requirement of the original SA40C. This part is suitable for all temperature profiles requiring -55°C minimum operation.

Q: What packaging options are available for these substitutes?

A: All substitute parts are supplied in DO-204AC / DO-15 axial through-hole packages. Packaging configurations (bulk, tape & reel) vary by manufacturer and supplier. Verify specific packaging availability with your component distributor.