P4SMA9.1C Equivalent & Substitute Parts

Part Overview

The P4SMA9.1C is a transient voltage suppressor (TVS) diode manufactured by Littelfuse, designed for general-purpose overvoltage protection in surface mount applications. This part operates with a reverse standoff voltage of 7.78V and a maximum clamping voltage of 14.07V at peak pulse current. The P4SMA9.1C is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement.

Substiute Parts

P4SMA9.1C

LittelfuseIn Stock: 888P4SMA9.1C Datasheet

Current PartRFQ

P4SMA9.1CA

Taiwan Semiconductor CorporationIn Stock: 24123P4SMA9.1CA Datasheet

DirectRFQ

SMAJ7.5CA

MDDIn Stock: 65249SMAJ7.5CA Datasheet

MFR RecommendedRFQ

SMAJ8.0CA

MDDIn Stock: 50165SMAJ8.0CA Datasheet

MFR RecommendedRFQ

SMAJ8.5CA

MDDIn Stock: 72471SMAJ8.5CA Datasheet

MFR RecommendedRFQ

SMAJ9.0CA

MDDIn Stock: 54184SMAJ9.0CA Datasheet

MFR RecommendedRFQ

SMAJ7.5CA-M3/5A

Vishay General Semiconductor - Diodes DivisionIn Stock: 741SMAJ7.5CA-M3/5A Datasheet

MFR RecommendedRFQ

SMAJ8.0CA-M3/61

Vishay General Semiconductor - Diodes DivisionIn Stock: 1047SMAJ8.0CA-M3/61 Datasheet

MFR RecommendedRFQ

SMAJ9.0CA-TP

Micro Commercial CoIn Stock: 1131SMAJ9.0CA-TP Datasheet

MFR RecommendedRFQ

SMAJP4KE9.1CA-TP

Micro Commercial CoIn Stock: 1002SMAJP4KE9.1CA-TP Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the P4SMA9.1C is determined by the following electrical and mechanical parameters:

• Reverse Standoff Voltage (Typ): Must remain within the 7.78V specification to maintain circuit protection thresholds
• Clamping Voltage (Max) @ Ipp: Must not exceed 14.07V to ensure adequate transient suppression
• Peak Pulse Current (10/1000µs): Must support minimum 30.6A to handle expected surge conditions
• Power - Peak Pulse: Must maintain 400W rating for thermal performance
• Package / Case: Must be DO-214AC (SMA) for mechanical and electrical compatibility
• Mounting Type: Must be Surface Mount for PCB assembly compatibility
• RoHS Status: Must maintain ROHS3 compliance for regulatory requirements

Substitute parts are grouped into two categories: direct equivalents from alternative manufacturers and functionally compatible alternatives with similar electrical characteristics within acceptable tolerance ranges.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: P4SMA9.1CA

The P4SMA9.1CA from Taiwan Semiconductor Corporation is the closest electrical equivalent to the P4SMA9.1C. It maintains identical reverse standoff voltage (7.78V) and peak pulse current (31A), with a marginally lower clamping voltage (13.4V vs 14.07V). This part is active in production and ROHS3 compliant. The operating temperature range is -55°C to 150°C, which is narrower than the original but suitable for most general-purpose applications.

Secondary Substitutes: SMAJP4KE9.1CA-TP

The SMAJP4KE9.1CA-TP from Micro Commercial Co provides an alternative with matching reverse standoff voltage (7.78V) and peak pulse current (30.6A). This part is active and ROHS3 compliant with an extended operating temperature range of -55°C to 175°C. The clamping voltage is 13.4V.

Alternative Substitutes with Voltage Variations

Parts including SMAJ7.5CA, SMAJ8.0CA, SMAJ8.5CA, and SMAJ9.0CA from MDD, along with Vishay variants SMAJ7.5CA-M3/5A and SMAJ8.0CA-M3/61, offer functional alternatives with different reverse standoff voltages. These parts maintain the 400W power rating and DO-214AC package compatibility but operate at different voltage thresholds. Selection among these alternatives depends on specific circuit protection requirements and acceptable voltage deviation from the original 7.78V specification.

All substitute parts maintain ROHS3 compliance and are available in active production status, ensuring long-term supply availability.

Frequently Asked Questions (FAQ)

Q: Can I use SMAJ9.0CA-TP as a direct replacement for P4SMA9.1C?

A: SMAJ9.0CA-TP is functionally compatible but not a direct replacement. While it maintains the 400W power rating and DO-214AC package, the reverse standoff voltage is 9V (versus 7.78V) and clamping voltage is 15.4V (versus 14.07V). This part is suitable only if your circuit can tolerate higher voltage thresholds.

Q: What is the key difference between P4SMA9.1CA and SMAJP4KE9.1CA-TP?

A: Both parts share identical reverse standoff voltage (7.78V) and peak pulse current (30.6A). The primary difference is the operating temperature range: P4SMA9.1CA operates from -55°C to 150°C, while SMAJP4KE9.1CA-TP extends to 175°C. Both are ROHS3 compliant and available in active production.

Q: Are all substitute parts available in the same package?

A: Yes. All listed substitute parts use the DO-214AC (SMA) package for surface mount applications, ensuring mechanical and electrical compatibility with the original P4SMA9.1C footprint.

Q: Why does the P4SMA9.1C have a wider operating temperature range than most substitutes?

A: The P4SMA9.1C operates from -65°C to 150°C, while most active substitutes operate from -50°C to -55°C minimum. This reflects manufacturing and design differences between Littelfuse and alternative manufacturers. For applications requiring the full -65°C lower limit, P4SMA9.1CA or SMAJP4KE9.1CA-TP with -55°C minimum are the closest alternatives.

Q: What is the significance of the clamping voltage differences?

A: Clamping voltage determines the maximum voltage the TVS diode allows across the protected circuit during a transient event. The P4SMA9.1C clamps at 14.07V maximum. Substitutes with lower clamping voltages (such as SMAJ7.5CA at 12.9V) provide tighter protection, while those with higher clamping voltages (such as SMAJ9.0CA at 15.4V) allow higher transient voltages. Selection depends on the protected circuit's voltage tolerance.

Q: Are all substitute parts ROHS3 compliant?

A: Yes. All listed substitute parts maintain ROHS3 compliance, meeting regulatory requirements for hazardous substance restrictions.