STP7N52K3 N-Channel MOSFET Equivalent & Substitute Parts

Part Overview

The STP7N52K3 is an N-Channel MOSFET manufactured by STMicroelectronics, rated for 525V drain-to-source voltage with 6A continuous drain current in a Through Hole TO-220 package. This device is part of the SuperMESH3™ series and is classified as Obsolete. Due to its obsolete status, equivalent and substitute parts are necessary for ongoing production, maintenance, and design continuity in applications requiring high-voltage N-Channel MOSFET functionality.

Substiute Parts

STP7N52K3

STMicroelectronicsIn Stock: 1050STP7N52K3 Datasheet

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AOT8N50

Alpha & Omega Semiconductor Inc.In Stock: 18824AOT8N50 Datasheet

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FQP6N40CF

onsemiIn Stock: 1938FQP6N40CF Datasheet

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IRF840APBF

Vishay SiliconixIn Stock: 19023IRF840APBF Datasheet

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IRF840PBF

Vishay SiliconixIn Stock: 329788IRF840PBF Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the STP7N52K3 is determined by the following critical parameters:

Voltage Rating Compatibility: Substitute parts must maintain a Vdss rating equal to or greater than 525V to ensure safe operation in the original application circuit.

Current Rating Compatibility: Substitute parts must support a continuous drain current (Id) equal to or greater than 6A at 25°C to handle the design load requirements.

On-State Resistance (Rds On): Substitute parts must maintain comparable or lower Rds On values to ensure thermal performance and power dissipation characteristics remain within acceptable limits.

Package Compatibility: All substitute parts must use the Through Hole TO-220-3 package to ensure mechanical and thermal compatibility with existing PCB layouts and heatsinking arrangements.

Regulatory Compliance: All substitute parts must maintain ROHS3 compliance and equivalent environmental certifications.

Based on these criteria, the following parts are identified as substitutes:

Group 1 (Higher Current Rating, Lower Voltage Rating): AOT8N50, IRF840APBF, IRF840PBF — These parts provide higher continuous drain current (8A) but operate at 500V Vdss, which is 25V below the original specification. These are suitable for applications where the 525V rating is not a hard requirement.

Group 2 (Lower Voltage Rating, Matched Current): FQP6N40CF — This part maintains the 6A current rating but operates at 400V Vdss, suitable only for applications with lower voltage requirements.

Parameter Comparison

Engineering Selection Recommendations

For Direct Voltage and Current Replacement (525V, 6A):

No substitute part in the provided list maintains both the 525V Vdss rating and 6A current specification. The STP7N52K3 represents a unique combination of high voltage and moderate current in this component set.

For 500V Applications (Acceptable Voltage Reduction):

IRF840PBF and IRF840APBF are both Active status parts manufactured by Vishay Siliconix. IRF840PBF offers significantly higher inventory availability (329,719 units) compared to IRF840APBF (18,922 units). Both parts provide 8A continuous drain current, exceeding the original 6A specification, and maintain ROHS3 compliance. The 25V reduction in Vdss (from 525V to 500V) must be evaluated against circuit design margins.

AOT8N50 from Alpha & Omega Semiconductor Inc. also operates at 500V with 8A current rating and is classified as Not For New Designs, limiting its suitability for new production applications.

For Lower Voltage Applications (400V):

FQP6N40CF from onsemi maintains the 6A current rating but operates at 400V Vdss. This part is Obsolete and suitable only for legacy applications or maintenance scenarios where 400V operation is acceptable.

Compliance Considerations:

All substitute parts maintain ROHS3 compliance. IRF840APBF and IRF840PBF carry REACH Affected status, whereas the main part and other substitutes are REACH Unaffected. This distinction may impact supply chain and regulatory requirements depending on application geography.

Frequently Asked Questions (FAQ)

Q: Can IRF840PBF directly replace STP7N52K3 in a 525V circuit?

A: IRF840PBF operates at 500V Vdss, which is 25V below the STP7N52K3 specification. Direct replacement is not recommended for circuits designed to operate at or near 525V. Circuit design margins must be evaluated to determine if 500V operation is acceptable.

Q: What is the primary difference between IRF840APBF and IRF840PBF?

A: Both parts share identical electrical specifications (500V, 8A, 850mOhm Rds On). The primary differences are Gate Charge (38 nC vs. 63 nC) and Input Capacitance (1018 pF vs. 1300 pF). IRF840PBF has significantly higher inventory availability.

Q: Is AOT8N50 suitable for new production designs?

A: AOT8N50 is classified as Not For New Designs. While it meets electrical requirements for 500V, 8A applications, its product status restricts use to legacy or maintenance applications only.

Q: Why does FQP6N40CF have lower power dissipation than STP7N52K3?

A: FQP6N40CF operates at 400V Vdss compared to STP7N52K3 at 525V. The lower voltage rating results in reduced power dissipation (73W vs. 90W) despite comparable current ratings. This part is suitable only for applications where 400V operation meets design requirements.

Q: Are all substitute parts available in the same TO-220-3 package?

A: Yes. All substitute parts listed use the Through Hole TO-220-3 package, ensuring mechanical and thermal compatibility with existing PCB layouts designed for STP7N52K3.

Q: What is the impact of Gate Charge differences on circuit performance?

A: Gate Charge (Qg) affects switching speed and gate drive requirements. STP7N52K3 specifies 34 nC, while IRF840PBF specifies 63 nC. Higher gate charge requires increased gate drive current or longer switching times. Circuit design must account for these differences in gate driver selection.

Q: Which substitute part offers the best long-term availability?

A: IRF840PBF, classified as Active status with 329,719 units in stock, offers the highest availability and longest product lifecycle support among the listed substitutes.