FDP39N20 Equivalent & Substitute Parts

Part Overview

The FDP39N20 is an N-Channel MOSFET manufactured by onsemi, rated for 200V drain-to-source voltage with 39A continuous drain current in a TO-220-3 through-hole package. This device is part of the UniFET™ series and is classified as obsolete. Due to its obsolete status, equivalent and substitute parts from active manufacturers are necessary for new designs and ongoing production requirements. Substitute devices must maintain electrical compatibility across voltage, current, and thermal specifications while accommodating available packaging options.

Key Parameters

Parameter	FDP39N20 Specification
Drain-to-Source Voltage (Vdss)	200 V
Continuous Drain Current (Id) @ 25°C	39 A (Tc)
On-State Resistance (Rds On Max) @ Id, Vgs	66 mOhm @ 19.5A, 10V
Gate Threshold Voltage (Vgs(th) Max) @ Id	5V @ 250µA
Gate Charge (Qg Max) @ Vgs	49 nC @ 10V
Power Dissipation (Max)	251 W (Tc)
Operating Temperature Range	-55°C to 150°C (TJ)
Package Type	TO-220-3
Mounting Type	Through Hole
FET Type	N-Channel
Technology	MOSFET (Metal Oxide)

Substitute Part Grouping Explanation

Substitution of the FDP39N20 is determined by the following critical parameters:

Electrical Compatibility Requirements:

Drain-to-Source Voltage (Vdss) must equal or exceed 200V
Continuous Drain Current (Id) must equal or exceed 39A at 25°C
Gate drive voltage compatibility at 10V
Gate threshold voltage (Vgs(th)) within acceptable range for 10V drive circuits
Operating temperature range must encompass -55°C to 150°C minimum

Mechanical Compatibility Requirements:

Through-hole mounting type
TO-220-3 package family (includes TO-220-3, TO-220AB, TO-220FM variants)
Pin configuration compatible with TO-220-3 footprint

Compliance Requirements:

RoHS3 compliance
REACH unaffected status
EAR99 classification

Substitute parts are grouped into three categories based on their relationship to the FDP39N20:

Direct Manufacturer Equivalent (MFR Recommended): FDP61N20 from onsemi—same manufacturer, same series, same voltage rating, higher current rating with improved thermal performance
Direct Substitutes (Similar): Parts meeting or exceeding all electrical parameters with compatible packaging
Functional Alternatives (Similar): Parts with higher voltage ratings or different thermal characteristics that maintain electrical compatibility

Parameter Comparison

Parameter	FDP39N20	FDP61N20	RCX330N25	IRFB4227PBF	IXTP50N20P	PSMN057-200P,127	STP30NF20	STP40NF20
Manufacturer	onsemi	onsemi	Rohm Semiconductor	Infineon Technologies	IXYS	Nexperia USA Inc.	STMicroelectronics	STMicroelectronics
Vdss (V)	200	200	250	200	200	200	200	200
Id @ 25°C (A)	39	61	33	65	50	39	30	40
Rds On Max (mOhm)	66 @ 19.5A, 10V	41 @ 30.5A, 10V	—	24 @ 46A, 10V	60 @ 50A, 10V	57 @ 17A, 10V	75 @ 15A, 10V	45 @ 20A, 10V
Vgs(th) Max (V)	5 @ 250µA	5 @ 250µA	—	5 @ 250µA	5 @ 250µA	4 @ 1mA	4 @ 250µA	4 @ 250µA
Qg Max (nC)	49 @ 10V	75 @ 10V	—	98 @ 10V	70 @ 10V	96 @ 10V	38 @ 10V	75 @ 10V
Power Dissipation Max (W)	251 (Tc)	417 (Tc)	40 (Tc)	330 (Tc)	360 (Tc)	250 (Tc)	125 (Tc)	160 (Tc)
Operating Temp Range (°C)	-55 to 150	-55 to 150	—	-40 to 175	-55 to 175	-55 to 175	-55 to 150	-55 to 150
Package	TO-220-3	TO-220-3	TO-220FM	TO-220AB	TO-220-3	TO-220AB	TO-220	TO-220
Product Status	Obsolete	Active	Active	Active	Active	Active	Active	Active
RoHS3 Compliant	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes

Engineering Selection Recommendations

Primary Recommendation: FDP61N20

The FDP61N20 is the manufacturer-recommended equivalent from onsemi. It maintains identical voltage rating (200V Vdss), belongs to the same UniFET™ series, and provides superior electrical performance with 61A continuous drain current versus 39A. The device is in active production status, ensuring long-term availability. On-state resistance is reduced to 41 mOhm, improving thermal efficiency. Power dissipation capability increases to 417W, providing design margin. Operating temperature range remains -55°C to 150°C. This part is the direct replacement for new designs and production transitions.

Secondary Recommendations for Current-Matched Performance:

PSMN057-200P,127 (Nexperia USA Inc.) provides identical 39A current rating and 200V voltage rating with 250W power dissipation. This part matches the original electrical envelope precisely. It is in active production with RoHS3 compliance. Gate charge is higher at 96 nC, and operating temperature extends to 175°C. Package is TO-220AB, compatible with TO-220-3 footprints.

STP40NF20 (STMicroelectronics) provides 40A continuous drain current, exceeding the 39A requirement by 1A. Voltage rating is 200V. Power dissipation is 160W, lower than the original 251W specification. This part is suitable for applications with reduced thermal requirements. Operating temperature range is -55°C to 150°C. On-state resistance is 45 mOhm at 20A, 10V.

Higher Current Alternatives for Thermal Margin:

IXTP50N20P (IXYS) provides 50A continuous drain current with 200V voltage rating and 360W power dissipation. On-state resistance is 60 mOhm. This part offers increased current capacity and thermal headroom for demanding applications. Operating temperature extends to 175°C.

IRFB4227PBF (Infineon Technologies) provides 65A continuous drain current with 200V voltage rating and 330W power dissipation. On-state resistance is 24 mOhm, the lowest among all substitutes. This part is suitable for high-efficiency applications requiring minimal conduction losses. Operating temperature extends to 175°C. High inventory availability (34,054 pcs) ensures supply continuity.

Higher Voltage Alternative:

RCX330N25 (Rohm Semiconductor) provides 250V drain-to-source voltage with 33A continuous drain current. This part is suitable for applications requiring higher voltage margin. Package is TO-220FM. Operating temperature maximum is 150°C. Power dissipation is 40W (Tc). This part is appropriate for circuits operating near 200V where additional voltage headroom is beneficial.

All recommended substitutes maintain RoHS3 compliance, REACH unaffected status, and EAR99 classification. All are in active production status, ensuring long-term availability and supply chain stability.

Frequently Asked Questions (FAQ)

Q: Can FDP61N20 be used as a direct replacement for FDP39N20?

A: Yes. FDP61N20 is the manufacturer-recommended equivalent from onsemi. It maintains the same 200V voltage rating, belongs to the same UniFET™ series, and is pin-compatible in TO-220-3 packaging. The higher 61A current rating and improved on-state resistance (41 mOhm versus 66 mOhm) provide superior performance. It is in active production status, addressing the obsolescence of FDP39N20.

Q: What is the difference between TO-220-3, TO-220AB, and TO-220FM packages?

A: All three are through-hole packages with compatible pin configurations for N-Channel MOSFETs. TO-220-3 is the standard variant. TO-220AB is an alternative designation used by some manufacturers. TO-220FM is a full-pack variant with different mechanical mounting features. All are electrically compatible with TO-220-3 footprints, though mechanical mounting may require verification for specific PCB designs.

Q: Which substitute provides the lowest on-state resistance?

A: IRFB4227PBF provides the lowest on-state resistance at 24 mOhm (measured at 46A, 10V). This reduces conduction losses and heat generation in high-current applications. However, this part has higher gate charge (98 nC) compared to FDP39N20 (49 nC), which may affect switching speed in gate-drive-limited circuits.

Q: Can I use STP30NF20 or STP40NF20 as substitutes?

A: STP30NF20 provides only 30A continuous drain current, which is below the 39A requirement of FDP39N20. This part is not suitable as a direct substitute. STP40NF20 provides 40A continuous drain current, exceeding the 39A requirement by 1A, and is suitable for applications with reduced thermal requirements. Power dissipation is 160W, lower than the original 251W specification.

Q: What is the impact of higher gate charge on circuit performance?

A: Gate charge (Qg) determines the amount of charge required to switch the MOSFET on and off. Higher gate charge requires more current from the gate driver and increases switching time. FDP39N20 has 49 nC gate charge. Substitutes with higher gate charge (such as IRFB4227PBF at 98 nC) may require gate drivers with higher current capability. Substitutes with lower gate charge (such as STP30NF20 at 38 nC) reduce gate driver stress.

Q: Is RCX330N25 suitable for 200V applications?

A: RCX330N25 is rated for 250V drain-to-source voltage, which exceeds the 200V requirement. This part is suitable for 200V applications and provides additional voltage margin. However, the continuous drain current is 33A, which is below the 39A requirement. This part is appropriate only for applications where current requirements are lower than 39A or where higher voltage rating is beneficial.

Q: What is the significance of product status (Active vs. Obsolete)?

A: Active status indicates the manufacturer continues production and supports the part with technical documentation and supply chain availability. Obsolete status indicates the manufacturer has discontinued production. FDP39N20 is obsolete, making substitution necessary for new designs and long-term production. All recommended substitutes are in active production status, ensuring availability and manufacturer support.

Q: Are all substitutes RoHS3 compliant?

A: Yes. All recommended substitutes are RoHS3 compliant and REACH unaffected. They meet the same environmental and regulatory requirements as FDP39N20. All are classified as EAR99 for export control purposes.

Q: Which substitute has the highest power dissipation capability?

A: FDP61N20 has the highest power dissipation capability at 417W (Tc), compared to FDP39N20 at 251W (Tc). This provides significant thermal margin for high-power applications. IRFB4227PBF provides 330W, and IXTP50N20P provides 360W, both offering substantial thermal headroom.

Q: Can I use multiple substitutes interchangeably in the same design?

A: Substitutes with identical electrical specifications (voltage, current, gate drive) and compatible packages can be used interchangeably if the circuit design accommodates parameter variations. However, differences in on-state resistance, gate charge, and input capacitance may affect circuit performance. Gate driver design must accommodate the gate charge and threshold voltage of the selected part. Thermal design must account for the power dissipation of the selected part.

Request Quote (Ships tomorrow)

Part Number

Quantity

Company

Contact Name

E-mail

Message