P4SMA20 Equivalent & Substitute Parts

Part Overview

The P4SMA20 is a unidirectional Zener transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection in surface-mount applications. The device features a 17.1V reverse standoff voltage, 29.09V maximum clamping voltage, and 14.8A peak pulse current capability in a DO-214AC (SMA) package. The P4SMA20 is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements.

Substiute Parts

P4SMA20

Littelfuse Inc.In Stock: 2148P4SMA20 Datasheet

Current PartRFQ

P4SMA20A

Eaton - Electronics DivisionIn Stock: 66610P4SMA20A Datasheet

MFR RecommendedRFQ

P4SMA20A

Eaton - Electronics DivisionIn Stock: 66610P4SMA20A Datasheet

MFR RecommendedRFQ

SMAJP4KE20A-TP

Micro Commercial CoIn Stock: 5420SMAJP4KE20A-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the P4SMA20 are qualified based on the following critical electrical and mechanical parameters:

• Voltage - Reverse Standoff (Typ): 17.1V
• Voltage - Clamping (Max) @ Ipp: Maximum 29.09V
• Current - Peak Pulse (10/1000µs): 14.8A
• Power - Peak Pulse: 400W
• Package / Case: DO-214AC, SMA
• Unidirectional Channels: 1
• Type: Zener

The substitute parts P4SMA20A and SMAJP4KE20A-TP meet these core electrical specifications and are compatible with the original P4SMA20 footprint and functional requirements. Both substitutes maintain the same reverse standoff voltage, peak pulse current, and power dissipation characteristics. Clamping voltage variations within the specified range do not affect circuit compatibility for general-purpose overvoltage protection applications.

Parameter Comparison

Engineering Selection Recommendations

Both P4SMA20A and SMAJP4KE20A-TP are active production alternatives to the obsolete P4SMA20. Selection between these substitutes depends on compliance and environmental requirements:

P4SMA20A (Eaton) is suitable for applications where RoHS compliance is not a design constraint. This part maintains the original operating temperature range lower limit of -55°C and is widely available in production quantities.

SMAJP4KE20A-TP (Micro Commercial Co) is the preferred choice for designs requiring ROHS3 compliance. This part extends the upper operating temperature limit to 175°C, providing additional thermal margin for high-temperature applications. Both substitutes are actively manufactured and available in tape and reel packaging for automated assembly.

Frequently Asked Questions (FAQ)

Q: Can P4SMA20A and SMAJP4KE20A-TP be used interchangeably with the original P4SMA20?

A: Yes. Both substitutes maintain identical reverse standoff voltage (17.1V), peak pulse current (14.8A), and power dissipation (400W). The clamping voltage differences (27.7V vs. 29.09V) remain within acceptable operating margins for general-purpose overvoltage protection circuits. Footprint and mounting type are identical.

Q: What is the difference in clamping voltage between the original and substitute parts?

A: The P4SMA20 specifies a maximum clamping voltage of 29.09V, while both substitutes specify 27.7V. This 1.39V reduction does not affect circuit functionality in standard protection applications, as the clamping voltage remains well below typical component damage thresholds.

Q: Are there RoHS compliance differences between the substitutes?

A: Yes. P4SMA20A is RoHS non-compliant, while SMAJP4KE20A-TP is ROHS3 compliant. For designs requiring RoHS certification, SMAJP4KE20A-TP is the appropriate selection.

Q: Do the substitutes support the same operating temperature range?

A: The original P4SMA20 operates from -65°C to 150°C. Both substitutes operate from -55°C to 150°C, with SMAJP4KE20A-TP extending to 175°C. The -55°C lower limit is suitable for most commercial and industrial applications.

Q: Are both substitutes available in the same packaging format?

A: Yes. Both P4SMA20A and SMAJP4KE20A-TP are supplied in tape and reel (TR) packaging, compatible with standard surface-mount assembly equipment and processes.