FQB7N80TM_AM002 Equivalent & Substitute Parts

Part Overview

The FQB7N80TM_AM002 is an N-Channel MOSFET manufactured by onsemi, rated for 800V drain-to-source voltage with 6.6A continuous drain current at 25°C. This device is packaged in TO-263 (D2PAK) surface mount configuration and belongs to the QFET® series. The part is currently classified as obsolete, necessitating identification of active equivalent alternatives that maintain electrical and mechanical compatibility for ongoing production and repair applications.

Substiute Parts

FQB7N80TM_AM002

onsemiIn Stock: 724FQB7N80TM_AM002 Datasheet

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STB5N80K5

STMicroelectronicsIn Stock: 3416STB5N80K5 Datasheet

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STB6N80K5

STMicroelectronicsIn Stock: 2463STB6N80K5 Datasheet

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STB7NK80ZT4

STMicroelectronicsIn Stock: 5462STB7NK80ZT4 Datasheet

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STB9NK80Z

STMicroelectronicsIn Stock: 2012STB9NK80Z Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the FQB7N80TM_AM002 is determined by strict adherence to the following electrical and mechanical parameters:

Critical Matching Parameters:

• Drain-to-Source Voltage (Vdss): 800V (exact match required)
• Package Type: TO-263 (D2PAK) surface mount configuration
• FET Type: N-Channel MOSFET
• Operating Temperature Range: -55°C to 150°C (TJ)
• Gate Voltage Rating (Vgs Max): ±30V

Current Rating Consideration: The FQB7N80TM_AM002 specifies 6.6A continuous drain current. Substitute parts are grouped based on whether they meet, approach, or fall below this current specification. Parts with lower current ratings (4A, 4.5A) are classified as reduced-capacity substitutes suitable for applications with lower current demands. Parts with equal or higher current ratings (5.2A) are classified as direct or upgraded substitutes.

Secondary Parameters for Compatibility:

• On-State Resistance (Rds On): Lower values indicate improved performance
• Gate Charge (Qg): Lower values reduce switching losses
• Input Capacitance (Ciss): Affects gate drive requirements
• Power Dissipation: Determines thermal management requirements

All substitute parts listed maintain the same voltage rating, package configuration, and temperature operating range as the primary part.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitutes (Closest Electrical Match):

STB7NK80ZT4 and STB9NK80Z are the preferred substitutes for the FQB7N80TM_AM002. Both devices deliver 5.2A continuous drain current, which approaches the original 6.6A specification. Both maintain identical 800V Vdss rating, ±30V gate voltage rating, and TO-263 (D2PAK) package configuration. Both are active products with ROHS3 compliance. STB9NK80Z carries additional AEC-Q101 automotive qualification, making it suitable for automotive applications requiring formal qualification documentation.

Secondary Substitutes (Reduced Current Capacity):

STB5N80K5 and STB6N80K5 are suitable for applications where the full 6.6A current capacity is not required. STB5N80K5 provides 4A continuous drain current with the lowest gate charge (5nC), beneficial for applications prioritizing switching speed and reduced gate drive power. STB6N80K5 provides 4.5A continuous drain current with moderate gate charge (7.5nC), offering a balance between current capacity and switching characteristics. Both maintain 800V Vdss rating and TO-263 package compatibility.

Compliance Considerations:

All substitute parts are ROHS3 compliant and carry REACH Unaffected status, matching the environmental compliance profile of the original part. STB9NK80Z provides additional value through AEC-Q101 automotive qualification for applications requiring formal automotive component certification.

Thermal Management:

The FQB7N80TM_AM002 specifies 167W maximum power dissipation at Tc. STB7NK80ZT4 and STB9NK80Z both support 125W at Tc, requiring thermal design verification for applications approaching maximum power dissipation limits. STB6N80K5 supports 85W at Tc, and STB5N80K5 supports 60W at Tc, necessitating thermal analysis for high-power applications.

Frequently Asked Questions (FAQ)

Q: Can STB5N80K5 or STB6N80K5 directly replace the FQB7N80TM_AM002 in all applications?

A: STB5N80K5 and STB6N80K5 are mechanically and electrically compatible in terms of package, voltage rating, and temperature range. However, their continuous drain current ratings (4A and 4.5A respectively) are lower than the original 6.6A specification. These substitutes are suitable only for applications where the actual circuit current demand does not exceed their rated current capacity. Circuit analysis is required to confirm current compatibility.

Q: What is the difference between STB7NK80ZT4 and STB9NK80Z?

A: Both devices share identical electrical specifications: 5.2A continuous drain current, 800V Vdss, 1.8Ω Rds On, and 125W power dissipation at Tc. The primary difference is that STB9NK80Z carries AEC-Q101 automotive qualification and is designated as automotive grade, while STB7NK80ZT4 is a standard industrial-grade device. For automotive applications requiring formal qualification documentation, STB9NK80Z is the appropriate selection.

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

A: All substitute parts are packaged in TO-263-3 (D2PAK) surface mount configuration with 2 leads plus tab, identical to the FQB7N80TM_AM002. Printed circuit board layouts and thermal management designs require no modification for package compatibility.

Q: How do gate charge differences affect circuit performance?

A: Gate charge (Qg) determines the amount of charge required to switch the MOSFET on and off. The FQB7N80TM_AM002 specifies 52nC at 10V. STB5N80K5 (5nC) requires significantly less gate charge, reducing gate drive power and enabling faster switching. STB7NK80ZT4 (56nC) and STB9NK80Z (40nC) have comparable or slightly lower gate charge. Lower gate charge reduces switching losses but may require gate drive circuit verification to ensure adequate drive capability.

Q: What thermal considerations apply when substituting with lower current-rated devices?

A: Lower current-rated devices (STB5N80K5 at 4A, STB6N80K5 at 4.5A) dissipate less power at equivalent operating currents due to lower Rds On values in some cases. However, thermal design must account for the maximum power dissipation rating: STB5N80K5 (60W), STB6N80K5 (85W), versus the original 167W at Tc. Applications operating near maximum power dissipation require thermal analysis to confirm adequate heat dissipation with the substitute device.

Q: Is the FQB7N80TM_AM002 still available for purchase?

A: The FQB7N80TM_AM002 is classified as obsolete. Current inventory availability is limited to existing stock. For new designs and ongoing production, selection of an active substitute part is necessary. STB7NK80ZT4, STB9NK80Z, STB6N80K5, and STB5N80K5 are all active products with established supply chains.

Q: Can input capacitance differences affect circuit design?

A: Input capacitance (Ciss) affects gate drive circuit design and switching transient behavior. The FQB7N80TM_AM002 specifies 1850pF at 25V. STB7NK80ZT4 and STB9NK80Z both specify 1138pF at 25V (lower capacitance), while STB5N80K5 (177pF) and STB6N80K5 (255pF) have significantly lower capacitance. Lower input capacitance reduces gate drive power requirements and may improve switching speed. Gate drive circuits designed for the original part's capacitance will function with substitute parts but may operate with reduced switching losses.