P6SMB18CAT3 Equivalent & Substitute Parts

Part Overview

The P6SMB18CAT3 is a bidirectional transient voltage suppressor (TVS) diode manufactured by onsemi, rated for 600W peak pulse power with an 18V clamping voltage in SMB (DO-214AA) surface mount packaging. This component is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. The part is RoHS non-compliant and carries unlimited moisture sensitivity level (MSL 1), suitable for general transient protection applications in telecom and industrial environments.

Substiute Parts

P6SMB18CAT3

onsemiIn Stock: 2062P6SMB18CAT3 Datasheet

Current PartRFQ

P6SMB18CA

Eaton - Electronics DivisionIn Stock: 58036P6SMB18CA Datasheet

DirectRFQ

SM6T18CA

STMicroelectronicsIn Stock: 3757SM6T18CA Datasheet

SimilarRFQ

SMBJ16CA

EVVO SemiIn Stock: 29230SMBJ16CA Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the P6SMB18CAT3 is determined by the following critical parameters:

Mandatory Matching Criteria:

• Package type: DO-214AA / SMB surface mount form factor
• Power rating: 600W peak pulse power
• Bidirectional zener diode configuration
• Reverse standoff voltage: 15.3V nominal
• Operating temperature range: -55°C to 150°C minimum
• Moisture sensitivity level: MSL 1 (unlimited)

Acceptable Variation Range:

• Voltage breakdown (Min): 17.1V to 17.8V
• Voltage clamping (Max) @ Ipp: 25.2V to 32.5V
• Current peak pulse: 23.1A to 123A (10/1000µs or 8/20µs)

All three substitute parts meet these criteria while maintaining functional equivalence for transient voltage suppression applications. Variations in clamping voltage and peak current reflect different manufacturer specifications for the same nominal 18V class device.

Parameter Comparison

Engineering Selection Recommendations

P6SMB18CA (Eaton - Electronics Division) is the primary direct substitute. It maintains identical reverse standoff voltage (15.3V), matching breakdown voltage (17.1V), and equivalent 600W power rating. The part is in active production status with RoHS compliance and substantial inventory availability (58,000 pcs). This part is recommended for designs requiring strict parameter matching and long-term supply continuity.

SM6T18CA (STMicroelectronics) provides functional equivalence with identical reverse standoff and breakdown voltages. The higher clamping voltage (32.5V) and peak current rating (123A at 8/20µs) indicate enhanced transient suppression capability within the same package and power class. This part carries ROHS3 compliance and is suitable for applications requiring more aggressive clamping characteristics. Inventory is limited (3,660 pcs).

SMBJ16CA (EVVO Semi) operates at a slightly elevated reverse standoff voltage (16V) with comparable clamping voltage (26V) and peak current (23.1A). This part extends the operating temperature range to -65°C and carries ROHS3 compliance. Selection is appropriate when the 16V standoff voltage is acceptable for the application and extended low-temperature performance is required.

All three substitutes are active production parts with RoHS compliance, addressing the obsolescence and compliance limitations of the original P6SMB18CAT3.

Frequently Asked Questions (FAQ)

Q: Can P6SMB18CA directly replace P6SMB18CAT3 without circuit modification?

A: Yes. P6SMB18CA maintains identical reverse standoff voltage (15.3V), matching breakdown voltage (17.1V), and equivalent 600W power rating in the same DO-214AA SMB package. No circuit modifications are required for direct substitution.

Q: What is the difference between the clamping voltages listed for each substitute?

A: Clamping voltage variation (25.2V to 32.5V) reflects different manufacturer test conditions and specifications for the same nominal 18V class device. All values remain within acceptable transient suppression parameters for 15.3V standoff applications. Selection depends on whether lower clamping voltage (P6SMB18CA at 25.2V) or higher clamping voltage (SM6T18CA at 32.5V) better matches circuit protection requirements.

Q: Is the SMBJ16CA suitable as a substitute despite the 16V reverse standoff voltage?

A: SMBJ16CA is functionally equivalent for most applications. The 16V reverse standoff voltage is marginally higher than the 15.3V specification but remains within acceptable tolerance for transient voltage suppression. Verify that the 16V standoff voltage does not exceed circuit operating voltage limits before selection.

Q: Why do the peak current ratings differ between substitutes?

A: Peak current ratings reflect different pulse waveform standards used by manufacturers. P6SMB18CA and SMBJ16CA specify 10/1000µs waveforms (24.2A and 23.1A respectively), while SM6T18CA specifies an 8/20µs waveform (123A). All three parts deliver 600W peak pulse power and are equivalent for transient suppression applications.

Q: Are all substitute parts RoHS compliant?

A: P6SMB18CA, SM6T18CA, and SMBJ16CA are all RoHS compliant (RoHS or ROHS3 status). The original P6SMB18CAT3 is RoHS non-compliant. Substitution with any of these parts resolves RoHS compliance requirements for new designs.

Q: What is the inventory status for each substitute?

A: P6SMB18CA has the highest availability (58,000 pcs), followed by SMBJ16CA (29,200 pcs) and SM6T18CA (3,660 pcs). For long-term production requirements, P6SMB18CA is recommended due to superior inventory depth and active production status.

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

A: P6SMB18CA and SM6T18CA support -55°C to 150°C. SMBJ16CA extends the lower temperature limit to -65°C. All three parts meet or exceed the original -55°C to 150°C specification.