SFP9640 Equivalent & Substitute Parts

Part Overview

The SFP9640 is a P-Channel MOSFET manufactured by onsemi, rated for 200V drain-to-source voltage with 11A continuous drain current in a Through Hole TO-220-3 package. This device is classified as obsolete, making equivalent substitute parts necessary for new designs and ongoing production requirements. The SFP9640 serves applications requiring P-Channel switching and linear regulation in power management circuits, gate driver applications, and general-purpose switching topologies.

Substiute Parts

SFP9640

onsemiIn Stock: 1671SFP9640 Datasheet

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IRF9640LPBF

Vishay SiliconixIn Stock: 799IRF9640LPBF Datasheet

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IRF9640PBF

Vishay SiliconixIn Stock: 93141IRF9640PBF Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the SFP9640 is determined by electrical and mechanical parameter alignment across the following criteria:

Electrical Equivalence Requirements:

• Drain-to-Source Voltage (Vdss): 200V minimum
• Continuous Drain Current (Id): 11A minimum at 25°C
• Gate-Source Threshold Voltage (Vgs(th)): 4V maximum at 250µA
• On-State Resistance (Rds On): 500mOhm maximum at specified conditions
• Operating Temperature Range: -55°C to 150°C minimum

Mechanical Compatibility:

• Through Hole mounting technology
• Package footprint compatibility with TO-220-3 or equivalent land patterns

The substitute parts IRF9640PBF and IRF9640LPBF meet these electrical specifications. Both devices are manufactured by Vishay Siliconix and maintain P-Channel MOSFET topology with identical voltage and current ratings. The IRF9640PBF uses TO-220AB packaging (compatible with TO-220-3 footprints), while the IRF9640LPBF uses I2PAK (TO-262-3 Long Leads) packaging, which requires PCB layout verification for pin compatibility.

Parameter Comparison

Engineering Selection Recommendations

IRF9640PBF Selection Criteria: The IRF9640PBF is the primary substitute for direct replacement of the SFP9640. This device maintains TO-220AB packaging, which is mechanically and electrically compatible with TO-220-3 footprints. The IRF9640PBF is in active production status with ROHS3 compliance, ensuring long-term availability and regulatory alignment. Power dissipation capability (125W Tc) exceeds the original specification (123W Tc). Gate charge is reduced to 44nC compared to the original 59nC, resulting in improved switching efficiency. The maximum gate-source voltage is reduced to ±20V from ±30V; circuit designs must confirm gate drive voltage does not exceed this limit.

IRF9640LPBF Selection Criteria: The IRF9640LPBF provides electrical equivalence with identical voltage, current, and thermal specifications. This device uses I2PAK (TO-262-3 Long Leads) packaging, which differs mechanically from the original TO-220-3. Selection of this part requires PCB redesign to accommodate the different pin configuration and spacing. The I2PAK package offers improved thermal performance in certain mounting configurations. This substitute is suitable only when PCB layout modifications are feasible and thermal performance improvements justify the redesign effort.

Compliance Considerations: Both substitute parts carry ROHS3 compliance certification, meeting current environmental and regulatory requirements. The original SFP9640 is marked as REACH Unaffected, while both Vishay substitutes are REACH Affected, indicating compliance with REACH regulations. This distinction does not affect functional compatibility but reflects current regulatory status.

Frequently Asked Questions (FAQ)

Q: Can the IRF9640PBF directly replace the SFP9640 without PCB modifications?

A: Yes. The IRF9640PBF uses TO-220AB packaging, which is mechanically compatible with TO-220-3 footprints. Pin assignments and lead spacing are equivalent, allowing direct substitution without PCB layout changes. Electrical parameters meet or exceed the original specification.

Q: What is the difference between IRF9640PBF and IRF9640LPBF?

A: Both devices have identical electrical specifications. The primary difference is packaging: IRF9640PBF uses TO-220AB (standard TO-220 footprint), while IRF9640LPBF uses I2PAK (TO-262-3 Long Leads). The I2PAK package has different pin spacing and requires PCB redesign. Selection depends on available PCB real estate and thermal management requirements.

Q: Are there gate drive voltage compatibility concerns with the substitutes?

A: Yes. The original SFP9640 specifies Vgs (Max) of ±30V, while both Vishay substitutes limit this to ±20V. Circuits applying gate-source voltages between ±20V and ±30V must be redesigned to operate within the ±20V limit of the substitute parts.

Q: How do the gate charge specifications affect circuit performance?

A: The substitute parts (IRF9640PBF and IRF9640LPBF) have reduced gate charge (44nC) compared to the original (59nC). Lower gate charge reduces switching losses and improves efficiency in high-frequency applications. Gate driver circuits designed for the original 59nC specification will operate with improved performance using the substitutes.

Q: What is the impact of reduced input capacitance in the substitutes?

A: The substitute parts have input capacitance (Ciss) of 1200pF compared to the original 1585pF. This 24% reduction decreases gate drive current requirements and switching losses. Circuits designed for the original specification will experience improved switching characteristics with the substitutes.

Q: Are the substitute parts suitable for new production designs?

A: Yes. Both IRF9640PBF and IRF9640LPBF are in active production status with ROHS3 compliance. These parts are recommended for new designs requiring P-Channel 200V/11A MOSFET functionality. The IRF9640PBF is the preferred choice for designs requiring minimal PCB modifications.

Q: What thermal performance differences exist between the parts?

A: All three devices support -55°C to 150°C operating temperature range. Power dissipation ratings are equivalent (123W to 125W at Tc). Thermal performance depends on PCB copper area, heatsinking, and airflow rather than device selection. The I2PAK package (IRF9640LPBF) may offer improved thermal coupling in specific mounting configurations.

Q: Is inventory availability a factor in substitute selection?

A: Yes. The IRF9640PBF has significantly higher inventory availability (93,100 pcs) compared to IRF9640LPBF (732 pcs). For production programs requiring sustained component supply, the IRF9640PBF is the more reliable choice.