3KP75C Equivalent & Substitute Parts

Part Overview

The 3KP75C is a bidirectional Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose transient voltage protection applications. This component features a 75V reverse standoff voltage rating with a 127.05V maximum clamping voltage and 24.8A peak pulse current capability in a through-hole P600 axial package. The product is currently classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing system maintenance and new design implementations where this protection topology is required.

Substiute Parts

3KP75C

Littelfuse Inc.In Stock: 11643KP75C Datasheet

Current PartRFQ

5KP75CA

Diotec SemiconductorIn Stock: 39405KP75CA Datasheet

DirectRFQ

15KP75CA-TP

Micro Commercial CoIn Stock: 78615KP75CA-TP Datasheet

MFR RecommendedRFQ

30KP75CA-TP

Micro Commercial CoIn Stock: 116730KP75CA-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 3KP75C is determined by strict alignment of the following electrical and mechanical parameters:

Primary Substitution Criteria:

• Voltage - Reverse Standoff (Typ): 75V (exact match required)
• Bidirectional Channels: 1 (single channel configuration)
• Type: Zener (TVS diode technology)
• Mounting Type: Through Hole (axial package form factor)
• RoHS3 Compliance (regulatory requirement)

Secondary Compatibility Parameters:

• Voltage - Breakdown (Min): Range 78.93V to 83.8V (acceptable variance)
• Voltage - Clamping (Max) @ Ipp: Range 119.4V to 127.05V (acceptable variance)
• Operating Temperature Range: Minimum -55°C to 175°C (must meet or exceed)
• Package / Case: P600 or R-6 axial configurations (mechanically compatible)

The three substitute parts listed below meet all primary criteria and fall within acceptable ranges for secondary parameters, ensuring functional equivalence for general-purpose transient voltage suppression applications.

Parameter Comparison

Engineering Selection Recommendations

5KP75CA (Diotec Semiconductor): This substitute maintains the P600 axial package form factor, ensuring direct mechanical compatibility with existing PCB layouts designed for the 3KP75C. The 5KP75CA delivers enhanced peak pulse power (5kW versus 3kW) and higher peak pulse current (41A versus 24.8A), providing improved transient suppression capability. Product status is active with full ROHS3 compliance. The operating temperature range extends to -50°C minimum, which is acceptable for most general-purpose applications requiring -55°C operation only in specialized environments.

15KP75CA-TP (Micro Commercial Co): This substitute transitions to the R-6 axial package, requiring PCB layout verification for mechanical fit. The 15KP75CA-TP provides significantly enhanced peak pulse power (15kW) suitable for higher-energy transient events. Product status is active with full ROHS3 compliance and REACH unaffected designation. Operating temperature range matches the original specification (-55°C to 175°C). This option is appropriate when system requirements demand greater transient energy absorption capacity.

30KP75CA-TP (Micro Commercial Co): This substitute also uses the R-6 axial package and delivers the highest peak pulse power rating (30kW) among available alternatives. Selection of this part is justified when system designs require maximum transient suppression capability or when protecting higher-energy circuit paths. Product status is active with full ROHS3 compliance and REACH unaffected designation. Operating temperature range matches the original specification (-55°C to 175°C).

All three substitutes maintain the critical 75V reverse standoff voltage and bidirectional single-channel configuration required for functional equivalence in general-purpose transient voltage suppression applications.

Frequently Asked Questions (FAQ)

Q: Can the 5KP75CA directly replace the 3KP75C without PCB modifications?

A: Yes. The 5KP75CA uses the same P600 axial package as the 3KP75C, enabling direct mechanical and electrical substitution without PCB layout changes. Both components feature identical through-hole lead spacing and package dimensions.

Q: Why do the 15KP75CA-TP and 30KP75CA-TP use different package designations (R-6 versus P600)?

A: The R-6 package is a higher-power variant of the axial through-hole form factor, designed to accommodate increased power dissipation. While mechanically similar, the R-6 package may have different lead spacing or body dimensions. PCB layout verification is required before substitution.

Q: What is the significance of the higher power ratings (5kW, 15kW, 30kW) in the substitute parts?

A: Higher power ratings indicate greater transient energy absorption capability. These substitutes can suppress larger voltage transients or longer-duration pulses without exceeding maximum junction temperature limits. Selection depends on the actual transient energy present in the application circuit.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. The 5KP75CA, 15KP75CA-TP, and 30KP75CA-TP are all ROHS3 compliant, meeting the same regulatory requirements as the original 3KP75C.

Q: Does the 5KP75CA operating temperature minimum of -50°C instead of -55°C affect compatibility?

A: For applications requiring operation at -55°C, the 5KP75CA is not suitable. The 15KP75CA-TP and 30KP75CA-TP both maintain the -55°C minimum specification and are appropriate for such requirements.

Q: What is the difference between the 15KP75CA-TP and 30KP75CA-TP substitutes?

A: Both parts share identical electrical specifications (75V standoff, 75V reverse voltage class) and package type (R-6 axial). The primary difference is peak pulse power rating: 15kW versus 30kW. Selection between these options depends on the magnitude of transient energy in the protected circuit.

Q: Can I use a substitute part with higher peak pulse power than required by my application?

A: Yes. Using a substitute with higher power rating than required does not create compatibility issues. The component will operate within its safe operating area at lower power levels. However, cost and board space considerations may favor selecting a substitute matched to actual application requirements.