SLD43U-017-B Equivalent & Substitute Parts

Part Overview

The SLD43U-017-B is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., rated for 43V reverse standoff voltage with a 69.4V clamping voltage and 74.6A peak pulse current. This component is designed for through-hole mounting in the P600 axial package and is qualified to AEC-Q101 automotive standards. The part is currently active in production with 995 units in stock. Equivalent and substitute parts are identified based on matching electrical characteristics and mechanical compatibility within the TVS diode category.

Substiute Parts

SLD43U-017-B

Littelfuse Inc.In Stock: 1075SLD43U-017-B Datasheet

Current PartRFQ

5KP43A

Littelfuse Inc.In Stock: 34105KP43A Datasheet

MFR RecommendedRFQ

3KP43A-TP

Micro Commercial CoIn Stock: 12493KP43A-TP Datasheet

MFR RecommendedRFQ

5KP43A-E3/54

Vishay General Semiconductor - Diodes DivisionIn Stock: 81645KP43A-E3/54 Datasheet

MFR RecommendedRFQ

5KP43A-TP

Micro Commercial CoIn Stock: 11985KP43A-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the SLD43U-017-B are identified based on the following critical parameters that determine functional equivalence:

• Voltage - Reverse Standoff (Typ): 43V
• Voltage - Clamping (Max) @ Ipp: 69.4V
• Power - Peak Pulse: 5000W (5kW)
• Operating Temperature Range: -55°C ~ 175°C (TJ)
• Unidirectional Channels: 1
• Type: Zener
• Mounting Type: Through Hole
• RoHS Status: ROHS3 Compliant

Substitutes are grouped into two categories based on package compatibility:

Category A - P600 Axial Package (Direct Mechanical Compatibility):

• 5KP43A (Littelfuse Inc.)
• 5KP43A-E3/54 (Vishay General Semiconductor - Diodes Division)

Category B - R-6 Axial Package (Alternative Mechanical Form):

• 3KP43A-TP (Micro Commercial Co)
• 5KP43A-TP (Micro Commercial Co)

All substitute parts maintain the specified voltage ratings, temperature range, and RoHS compliance. Package differences require mechanical board layout verification.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (P600 Package):

5KP43A and 5KP43A-E3/54 are direct mechanical and electrical equivalents to the SLD43U-017-B. Both maintain identical voltage ratings, clamping characteristics, and 5kW peak pulse power rating. Both are active products with ROHS3 compliance. The 5KP43A-E3/54 from Vishay carries the TransZorb® series designation and shows 72A peak pulse current versus 74.6A for the original part, representing a minor variance within acceptable substitution parameters. Selection between these two depends on supply chain availability and preferred manufacturer qualification.

Secondary Substitutes (R-6 Package):

3KP43A-TP and 5KP43A-TP from Micro Commercial Co provide electrical equivalence but require mechanical board layout modification due to R-6 package form factor. The 3KP43A-TP is rated for 3000W peak pulse power, which is lower than the 5000W specification of the original part. The 5KP43A-TP maintains the 5000W rating and is the preferred option within this package category if R-6 form factor is acceptable for the application.

All substitute parts are active products with ROHS3 compliance and unlimited moisture sensitivity level (MSL 1).

Frequently Asked Questions (FAQ)

Q: Can 5KP43A be used as a direct replacement for SLD43U-017-B?

A: Yes. The 5KP43A maintains identical voltage ratings (43V reverse standoff, 69.4V clamping), peak pulse power (5000W), and operating temperature range (-55°C to 175°C). Both use P600 axial through-hole packaging. The primary difference is packaging format (bulk versus cut tape), which does not affect electrical performance.

Q: What is the difference between P600 and R-6 packages?

A: P600 and R-6 are both axial through-hole packages for TVS diodes but differ in physical dimensions and lead spacing. P600 is the package used in the original SLD43U-017-B. R-6 packages (3KP43A-TP, 5KP43A-TP) require different PCB hole spacing and cannot be used without board layout modification.

Q: Why is 3KP43A-TP rated for 3000W instead of 5000W?

A: The 3KP43A-TP is a different product line within the Micro Commercial Co portfolio. While it maintains the same voltage characteristics and temperature range, its power dissipation capability is limited to 3000W. This part should only be selected if the application's peak pulse power requirement does not exceed 3000W.

Q: Are all substitute parts automotive qualified?

A: The SLD43U-017-B carries AEC-Q101 automotive qualification. The substitute parts listed (5KP43A, 5KP43A-E3/54, 3KP43A-TP, 5KP43A-TP) are all active products with ROHS3 compliance. Specific automotive qualification status for each substitute should be confirmed with the respective manufacturer if AEC-Q101 certification is a design requirement.

Q: Can I use 5KP43A-E3/54 if the original design specifies 74.6A peak pulse current?

A: The 5KP43A-E3/54 is rated for 72A peak pulse current, which is 1.5A lower than the 74.6A specification of the SLD43U-017-B. This represents a 1.9% variance. Substitution is acceptable if the circuit design includes margin above the 72A threshold. If the design operates at or near 74.6A, the original part or 5KP43A (74.6A rating) should be retained.

Q: What is the inventory status of substitute parts?

A: 5KP43A: 3339 units in stock; 3KP43A-TP: 1195 units in stock; 5KP43A-E3/54: 8100 units in stock; 5KP43A-TP: 1152 units in stock. All parts are available as new original stock.