RFP4N100 Equivalent & Substitute Parts

Part Overview

The RFP4N100 is an N-Channel 1000 V, 4.3 A (Tc) MOSFET manufactured by onsemi in a Through Hole TO-220-3 package. This device is classified as obsolete, necessitating identification of active equivalent and substitute components for new designs and ongoing production requirements. The RFP4N100 serves applications requiring high-voltage switching and power conversion where N-Channel MOSFET technology is specified.

Substiute Parts

RFP4N100

onsemiIn Stock: 2438RFP4N100 Datasheet

Current PartRFQ

STP5NK100Z

STMicroelectronicsIn Stock: 2382STP5NK100Z Datasheet

SimilarRFQ

STP8NK100Z

STMicroelectronicsIn Stock: 1498STP8NK100Z Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the RFP4N100 is determined by the following critical electrical and mechanical parameters:

Mandatory Matching Criteria:

• FET Type: N-Channel
• Technology: MOSFET (Metal Oxide)
• Drain to Source Voltage (Vdss): 1000 V
• Mounting Type: Through Hole
• Package / Case: TO-220-3

Functional Compatibility Criteria:

• Continuous Drain Current (Id) @ 25°C: Equal to or greater than 4.3 A (Tc)
• Rds On (Max) @ 10V: Equal to or lower than 3.5 Ohm (lower values indicate improved performance)
• Vgs(th) (Max): Within acceptable gate threshold voltage range
• Gate Charge (Qg): Lower values reduce switching losses

The substitute parts STP5NK100Z and STP8NK100Z meet all mandatory matching criteria and provide functional compatibility. Both devices are manufactured by STMicroelectronics, are classified as Active products, and comply with ROHS3 standards, addressing the obsolescence and compliance limitations of the RFP4N100.

Parameter Comparison

Engineering Selection Recommendations

STP5NK100Z Selection: The STP5NK100Z is suitable for applications where the RFP4N100 current rating of 4.3 A is not fully utilized. This device provides a continuous drain current of 3.5 A at 25°C, which is lower than the original specification. The STP5NK100Z is an Active product with ROHS3 compliance, addressing obsolescence and regulatory requirements. Gate charge is significantly reduced (59 nC versus 120 nC), resulting in lower switching losses. This substitute is appropriate for designs where current headroom is not critical and switching efficiency is prioritized.

STP8NK100Z Selection: The STP8NK100Z is the preferred substitute for direct functional replacement of the RFP4N100. This device provides a continuous drain current of 6.5 A at 25°C, exceeding the original 4.3 A specification and providing design margin. The on-resistance (Rds On) is significantly improved at 1.85 Ohm, reducing conduction losses compared to the RFP4N100's 3.5 Ohm specification. The STP8NK100Z is an Active product with ROHS3 compliance. The SuperMESH™ technology platform ensures compatibility with existing circuit topologies while delivering enhanced performance characteristics.

Both substitute parts maintain identical voltage ratings (1000 V Vdss), gate threshold voltage compatibility, and Through Hole TO-220-3 packaging, ensuring mechanical and electrical interchangeability within the specified parameter ranges.

Frequently Asked Questions (FAQ)

Q: Can the STP5NK100Z be used as a direct replacement for the RFP4N100?

A: The STP5NK100Z meets all mandatory electrical and mechanical compatibility criteria: N-Channel MOSFET technology, 1000 V Vdss rating, and TO-220-3 Through Hole package. However, the continuous drain current is 3.5 A versus the RFP4N100's 4.3 A. This substitute is suitable only if the application current requirement does not exceed 3.5 A at 25°C.

Q: What are the advantages of the STP8NK100Z over the RFP4N100?

A: The STP8NK100Z provides higher continuous drain current (6.5 A versus 4.3 A), significantly lower on-resistance (1.85 Ohm versus 3.5 Ohm), reduced gate charge (102 nC versus 120 nC), and Active product status with ROHS3 compliance. These characteristics result in improved thermal performance, reduced conduction losses, and faster switching characteristics.

Q: Are the substitute parts pin-compatible with the RFP4N100?

A: Yes. Both STP5NK100Z and STP8NK100Z use the TO-220-3 Through Hole package with identical pin configuration to the RFP4N100, enabling direct mechanical substitution without PCB modifications.

Q: What is the impact of the RFP4N100 being obsolete?

A: Obsolete status indicates the device is no longer manufactured or supported by onsemi. Active substitute parts ensure continued availability, manufacturer technical support, and compliance with current regulatory standards including ROHS3.

Q: How do gate charge differences affect circuit performance?

A: Gate charge (Qg) determines the energy required to switch the MOSFET on and off. The STP5NK100Z (59 nC) and STP8NK100Z (102 nC) both exhibit lower gate charge than the RFP4N100 (120 nC), resulting in reduced switching losses and improved efficiency in high-frequency applications.

Q: Are there thermal performance differences between the substitute parts?

A: The STP8NK100Z is rated for 160 W maximum power dissipation at Tc, compared to the STP5NK100Z at 125 W. The STP8NK100Z's lower on-resistance (1.85 Ohm) generates less heat during conduction, improving thermal efficiency in current-limited applications.

Q: Do the substitute parts require circuit modifications?

A: No circuit modifications are required. Both substitute parts maintain electrical compatibility within the specified parameter ranges. Existing gate drive circuits, protection networks, and thermal management solutions remain valid.