3KP12-B Equivalent & Substitute Parts

Part Overview

The 3KP12-B is a unidirectional Transient Voltage Suppressor (TVS) diode manufactured by Littelfuse Inc., rated for 12V reverse standoff voltage with a 20.9V maximum clamping voltage at peak pulse current of 150.8A. This through-hole P600 axial package component is designed for general-purpose transient voltage suppression applications across an operating temperature range of -55°C to 175°C.

The 3KP12-B is classified as obsolete. Equivalent and substitute parts are necessary to maintain design continuity and ensure component availability for new production runs and field replacements.

Substiute Parts

3KP12-B

Littelfuse Inc.In Stock: 11573KP12-B Datasheet

Current PartRFQ

5KP12A-B

Littelfuse Inc.In Stock: 12115KP12A-B Datasheet

DirectRFQ

3KP12A-TP

Micro Commercial CoIn Stock: 7883KP12A-TP Datasheet

MFR RecommendedRFQ

5KP12A-E3/54

Vishay General Semiconductor - Diodes DivisionIn Stock: 83225KP12A-E3/54 Datasheet

MFR RecommendedRFQ

5KP12AE3/TR13

Microchip TechnologyIn Stock: 12055KP12AE3/TR13 Datasheet

MFR RecommendedRFQ

5KP12AHE3/54

Vishay General Semiconductor - Diodes DivisionIn Stock: 11215KP12AHE3/54 Datasheet

MFR RecommendedRFQ

5KP12E3/TR13

Microchip TechnologyIn Stock: 10465KP12E3/TR13 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 3KP12-B is determined by the following critical parameters:

• Voltage Rating: Reverse standoff voltage of 12V and breakdown voltage minimum of 12.6V–13.3V
• Clamping Voltage: Maximum clamping voltage at peak pulse current (Ipp) ranging from 19.9V to 22V
• Peak Pulse Current: 150.8A to 256.3A at 10/1000µs pulse width
• Power Dissipation: 3000W to 5000W peak pulse power
• Package Type: Through-hole P600 or R-6 axial configuration
• Operating Temperature: -55°C to 175°C junction temperature
• Compliance: ROHS3 compliance and REACH status

Substitute parts are grouped into two categories:

Category 1 - Direct Electrical Equivalents (P600 Package) Parts with identical or superior electrical performance in the original P600 package, maintaining full form-factor compatibility.

Category 2 - Functional Equivalents (Alternative Package) Parts with compatible electrical specifications but alternative through-hole axial packages (R-6), suitable for applications where package footprint flexibility is acceptable.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (P600 Package - Direct Form-Factor Match)

The 5KP12A-B, 5KP12A-E3/54, and 5KP12AE3/TR13 are active production parts with identical P600 axial packaging. These parts maintain the original form factor and are suitable for direct board-level replacement. The 5KP12A-B offers higher peak pulse current (256.3A) and power dissipation (5000W) compared to the 3KP12-B, providing enhanced transient suppression capability. The 5KP12A-E3/54 and 5KP12AE3/TR13 deliver comparable performance with 251A peak pulse current and 5000W power rating. All three are ROHS3 compliant.

Secondary Substitute (R-6 Package - Alternative Through-Hole Configuration)

The 3KP12A-TP from Micro Commercial Co maintains the original 150.8A peak pulse current and 3000W power dissipation but uses an R-6 axial package instead of P600. This part is suitable for applications where package footprint variation is acceptable and provides electrical equivalence to the original 3KP12-B.

Automotive-Grade Option

The 5KP12AHE3/54 is qualified to AEC-Q101 automotive standards and is suitable for automotive and harsh-environment applications requiring enhanced reliability certification. This part maintains P600 packaging with 251A peak pulse current and 5000W power dissipation.

Extended Clamping Voltage Option

The 5KP12E3/TR13 provides a higher maximum clamping voltage of 22V at peak pulse current, compared to 19.9V in other 5KP series substitutes. This part is suitable for applications requiring higher transient voltage suppression thresholds while maintaining the 12V reverse standoff rating.

Frequently Asked Questions (FAQ)

Q: Can the 5KP12A-B directly replace the 3KP12-B on the PCB?

A: Yes. Both parts use the P600 axial through-hole package with identical pinout and footprint. The 5KP12A-B is a direct form-factor replacement. The higher peak pulse current (256.3A vs. 150.8A) and power dissipation (5000W vs. 3000W) provide enhanced performance without compatibility issues.

Q: What is the difference between the 5KP12A-E3/54 and 5KP12AE3/TR13?

A: Both parts have identical electrical specifications (12V standoff, 19.9V clamping, 251A peak pulse current, 5000W power). The primary difference is packaging format: 5KP12A-E3/54 is supplied in Cut Tape (CT), while 5KP12AE3/TR13 is supplied in Tape & Reel (TR). Selection depends on procurement and assembly requirements.

Q: Is the 3KP12A-TP a suitable replacement if the original P600 package is required?

A: The 3KP12A-TP uses an R-6 axial package, not P600. While electrically equivalent to the 3KP12-B (same 150.8A peak pulse current and 3000W power), it has a different physical footprint. Use this part only if the PCB layout can accommodate the R-6 package geometry.

Q: Why do some substitutes have higher peak pulse current ratings?

A: The 5KP series parts (5KP12A-B, 5KP12A-E3/54, 5KP12AE3/TR13, 5KP12AHE3/54) are rated for 5000W peak pulse power compared to the 3KP12-B's 3000W. This results in higher peak pulse current capability (251A–256.3A vs. 150.8A). These parts provide superior transient suppression performance and are suitable for applications with higher energy transient events.

Q: Is the 5KP12AHE3/54 required for all applications?

A: The 5KP12AHE3/54 carries AEC-Q101 automotive qualification. Use this part only if your application requires automotive-grade reliability certification. For general-purpose applications, other active substitutes are suitable.

Q: What is the significance of the clamping voltage difference between 19.9V and 22V?

A: The 5KP12E3/TR13 has a maximum clamping voltage of 22V, while other 5KP substitutes clamp at 19.9V. The 3KP12-B clamps at 20.9V. Select the 5KP12E3/TR13 if your circuit design requires a higher clamping threshold; otherwise, the 19.9V clamping parts are suitable.

Q: Are all substitutes ROHS3 compliant?

A: All listed substitutes except 3KP12A-TP are explicitly ROHS3 compliant. The 3KP12A-TP compliance status is not specified in the provided data. Verify ROHS3 compliance with the manufacturer if this certification is required for your application.