P4SMA350 Equivalent & Substitute Parts

Part Overview

The P4SMA350 is a unidirectional transient voltage suppressor (TVS) diode manufactured by Littelfuse Inc., designed for general-purpose overvoltage protection applications. This component features a 300V reverse standoff voltage, 506.1V maximum clamping voltage, and 400W peak pulse power rating in a surface-mount DO-214AC (SMA) package. The part is currently classified as obsolete, making equivalent substitute parts necessary for ongoing design support and procurement.

Substiute Parts

P4SMA350

Littelfuse Inc.In Stock: 1195P4SMA350 Datasheet

Current PartRFQ

P4SMA350A

Eaton - Electronics DivisionIn Stock: 20167P4SMA350A Datasheet

MFR RecommendedRFQ

P4SMA350A

Eaton - Electronics DivisionIn Stock: 20167P4SMA350A Datasheet

MFR RecommendedRFQ

SMAJ300A

MeritekIn Stock: 3720SMAJ300A Datasheet

MFR RecommendedRFQ

SMAJP4KE350A-TP

Micro Commercial CoIn Stock: 1162SMAJP4KE350A-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the P4SMA350 is determined by the following critical electrical and mechanical parameters:

Primary Substitution Criteria:

• Reverse standoff voltage: 300V (nominal)
• Unidirectional configuration: 1 channel
• Peak pulse current capability: 900mA minimum
• Peak pulse power rating: 400W
• Package type: DO-214AC (SMA) surface mount
• Clamping voltage range: 480V–510V @ Ipp

Secondary Compatibility Factors:

• Operating temperature range: minimum -55°C to 150°C
• RoHS compliance status
• Moisture sensitivity level: MSL 1

All substitute parts listed maintain the core electrical specifications within acceptable engineering tolerances for general-purpose and telecom applications. Variations in clamping voltage (482V–486V) and peak pulse current (820mA–900mA) remain within the functional envelope of the original P4SMA350 design.

Parameter Comparison

Engineering Selection Recommendations

P4SMA350A (Eaton - Electronics Division): This part is the manufacturer-recommended direct substitute. It maintains identical reverse standoff voltage (300V), peak pulse current (900mA), and power rating (400W). The clamping voltage is 482V, which is 24.1V lower than the original. Product status is active with full RoHS compliance and unlimited moisture sensitivity rating. Suitable for telecom and general-purpose applications.

SMAJP4KE350A-TP (Micro Commercial Co): This substitute offers the widest operating temperature range (-55°C to 175°C), exceeding the original specification. It maintains 900mA peak pulse current and 400W power rating with 482V clamping voltage. ROHS3 compliant with active product status. Recommended for applications requiring extended high-temperature performance.

SMAJ300A (Meritek): This part meets the core electrical requirements with 300V standoff voltage, 400W power rating, and DO-214AC package compatibility. Peak pulse current is 820mA, which is 80mA lower than the original. Clamping voltage is 486V. ROHS3 compliant and active product status. Suitable for general-purpose applications where the slightly reduced peak pulse current is acceptable.

All substitute parts maintain MSL 1 (unlimited) moisture sensitivity and are RoHS compliant, ensuring compatibility with modern manufacturing and environmental standards.

Frequently Asked Questions (FAQ)

Q: Can I use P4SMA350A as a direct replacement for P4SMA350?

A: Yes. P4SMA350A is the manufacturer-recommended substitute with identical reverse standoff voltage (300V), peak pulse current (900mA), and power rating (400W). The clamping voltage difference (482V vs. 506.1V) is within acceptable engineering tolerance for general-purpose and telecom protection circuits.

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

A: The primary differences are clamping voltage (482V–486V range) and peak pulse current (820mA–900mA). P4SMA350A and SMAJP4KE350A-TP maintain 900mA current capability, while SMAJ300A is rated at 820mA. All parts share the same 300V reverse standoff voltage and 400W power rating.

Q: Are all substitute parts in the same package?

A: Yes. All substitute parts use the DO-214AC (SMA) surface-mount package, ensuring mechanical and electrical compatibility with the original P4SMA350 footprint.

Q: Which substitute should I choose for high-temperature applications?

A: SMAJP4KE350A-TP offers the extended operating temperature range of -55°C to 175°C, compared to -55°C to 150°C for other substitutes. This part is recommended for designs requiring operation above 150°C.

Q: Are all substitute parts RoHS compliant?

A: Yes. All substitute parts listed are RoHS compliant (either RoHS or ROHS3 status), meeting environmental and regulatory requirements for modern electronics manufacturing.

Q: What is the impact of lower clamping voltage in substitute parts?

A: The substitute parts have clamping voltages of 482V–486V compared to the original 506.1V. This represents a 4–5% reduction and remains within acceptable design margins for 300V standoff voltage TVS diodes. Circuit designers should verify that the lower clamping voltage meets their specific overvoltage protection requirements.

Q: Can I use SMAJ300A if my circuit requires 900mA peak pulse current?

A: SMAJ300A is rated at 820mA peak pulse current, which is 80mA below the original specification. Use this part only if your circuit design can accommodate the reduced current rating or if peak pulse events are below 820mA.