IRF640NSTRLPBF 200V MOSFET for High Voltage Switching

ElecSuppliers Part Number GuideAug 28, 2026

When a power circuit needs to switch a voltage significantly higher than the typical 12 V or 24 V control rail, the MOSFET selection becomes much more important than simply finding a transistor with a large current rating.

IRF640NSTRLPBF is a 200 V N-channel power MOSFET from Infineon, based on the established IRF640N HEXFET platform. The device is specified for up to 18 A drain current at 25°C case temperature, with a maximum drain-source on-resistance of 150 mΩ when driven at 10 V. The exact part is supplied in a D2PAK surface-mount package.

That combination makes this part interesting for power switching designs where voltage margin, thermal performance and PCB assembly are all important.

Why the 200 V Rating Is the First Number to Look At

The most obvious specification of IRF640NSTRLPBF is its 200 V drain-source breakdown voltage.

This does not mean that the MOSFET should normally be operated continuously at 200 V with no additional design margin.

Instead, the 200 V rating defines the maximum drain-source voltage under the specified test conditions. The actual circuit needs to account for voltage spikes, switching transients, temperature and the required reliability margin.

This is particularly important in inductive switching circuits.

When current through an inductor is interrupted, the stored energy can generate a voltage spike. If that spike exceeds the MOSFET's voltage capability, the device can enter avalanche or suffer permanent damage.

The 200 V rating therefore provides the voltage boundary around which the power stage needs to be designed.

IRF640NSTRLPBF Is an N Channel MOSFET

The device uses an N-channel MOSFET structure.

In a typical low-side switching arrangement, the load is connected toward the positive supply and the MOSFET controls the path to ground.

The gate is electrically isolated from the main current path, allowing a relatively small control signal to regulate a much larger drain current.

For IRF640NSTRLPBF, the maximum gate-source voltage is ±20 V.

That does not mean that 20 V should be used as the normal gate-drive voltage.

The important RDS(on) specification is given at VGS = 10 V, so a conventional 10 V gate-drive condition is the reference point for its low on-resistance specification.

150 mΩ Is More Useful Than the 18 A Number Alone

IRF640NSTRLPBF is commonly described as an 18 A 200 V MOSFET, but current capability by itself does not tell you how much heat the device will generate.

The datasheet specifies a maximum RDS(on) of 0.15 Ω at VGS = 10 V and ID = 11 A.

When the MOSFET is turned on, this resistance produces conduction losses.

A simplified relationship is:

P = I² × RDS(on)

That means conduction loss increases rapidly as current increases.

For example, increasing the current from 5 A to 10 A does not simply double the resistive loss. Under the same resistance assumption, it increases the I² component by four times.

This is why thermal design becomes essential when a power MOSFET is operated at substantial current.

The 10 V Gate Drive Matters

One of the easiest mistakes when selecting a MOSFET is seeing a gate threshold voltage and assuming that it represents the voltage required to turn the device fully on.

For IRF640NSTRLPBF, the gate threshold range is specified around 2 V to 4 V, but the 150 mΩ on-resistance specification is tested at 10 V gate-source voltage.

These are two different specifications.

Gate threshold tells you approximately when the device begins to conduct under a very small specified test current.

It does not tell you the voltage needed for low-loss power switching.

For a power stage using IRF640NSTRLPBF, the gate-driver design should therefore be evaluated around the conditions under which the required RDS(on) performance is actually guaranteed.

Why D2PAK Changes the Design

The STR version is important because IRF640NSTRLPBF is not the same physical package as the through-hole IRF640NPBF.

Infineon identifies IRF640NSTRLPBF as a D2PAK device, while the standard IRF640N product page identifies the corresponding TO-220 version as IRF640NPBF.

Electrically, these devices belong to the same IRF640N family.

Mechanically, however, they are very different.

D2PAK allows the power transistor to be mounted directly onto a PCB and is well suited to automated surface-mount assembly.

TO-220, by comparison, is a through-hole package that is often easier to mount with an external heatsink.

So when a BOM specifically calls for IRF640NSTRLPBF, the package is part of the selection requirement rather than a minor detail.

What the D2PAK Package Offers

The D2PAK package gives designers a compact surface-mount way to handle a relatively high-power MOSFET.

The large metal tab provides a thermal path from the die to the PCB or thermal structure.

Infineon lists the device with a maximum power dissipation of 150 W at the case temperature reference, although the achievable power in an actual PCB depends heavily on board copper, thermal vias, airflow and operating conditions.

That distinction is important.

A 150 W package rating does not mean that a normal PCB can continuously dissipate 150 W.

The actual thermal design determines the operating temperature.

IRF640NSTRLPBF and Switching Frequency

The IRF640N family is an older-generation power MOSFET design, and Infineon specifically describes the device as optimized for applications switching below 100 kHz.

That is a useful piece of information when considering the part for a modern switching converter.

A MOSFET can have a perfectly adequate voltage and current rating but still be a poor choice at high switching frequencies because gate charge, capacitance and switching losses become increasingly important.

IRF640NSTRLPBF has a typical total gate charge around 44.7 nC at 10 V, with a maximum value of 67 nC reported by distributor specifications.

The gate driver must repeatedly charge and discharge this capacitance.

As switching frequency increases, the associated drive and transition losses become increasingly relevant.

The Body Diode Cannot Be Ignored

Like other power MOSFETs, IRF640NSTRLPBF contains an intrinsic body diode.

The datasheet specifies a typical diode forward voltage of approximately 1.3 V at 11 A and 25°C, with a reverse-recovery time of about 167 ns typical under the stated test conditions.

This becomes important in circuits where current can flow in the reverse direction during switching.

The body diode may participate in freewheeling paths, synchronous switching arrangements or transient current circulation.

Its reverse-recovery behavior can also influence switching losses and voltage spikes.

Therefore, the MOSFET should be evaluated as a complete switching device rather than only as a controllable resistance between drain and source.

Where IRF640NSTRLPBF Fits Naturally

The combination of 200 V voltage capability, 18 A current rating and surface-mount construction makes IRF640NSTRLPBF suitable for a range of medium-power switching applications.

Possible uses include:

High-voltage DC switching

Switch-mode power supplies

Motor control stages

Industrial power circuits

DC-DC conversion

Inverter-related power stages

Inductive load switching

The actual suitability depends on switching frequency, current waveform, thermal conditions and voltage transients.

It is not enough to compare only the nominal supply voltage.

High Voltage Does Not Mean High Efficiency Automatically

A 200 V MOSFET can still become hot in a circuit operating at a much lower voltage.

Suppose the MOSFET carries significant current.

Even when its drain-source voltage is very low in the fully enhanced state, the 150 mΩ maximum on-resistance can produce measurable conduction loss.

At higher current, that loss becomes increasingly important.

There are also switching losses when the MOSFET transitions between on and off states.

A successful power design therefore balances:

Voltage rating

Current

RDS(on)

Gate charge

Switching frequency

Thermal resistance

PCB layout

Gate-drive strength

Inductive transients

IRF640NSTRLPBF needs to be evaluated across all of these factors.

Thermal Design Is Part of the MOSFET Selection

Infineon specifies a maximum junction temperature of 175°C and a junction-to-case thermal resistance of approximately 1°C/W maximum for the device.

These figures are useful for thermal calculations, but they should not be interpreted as permission to run the component close to its maximum junction temperature in normal operation.

A practical design usually aims for a much more conservative temperature.

The D2PAK's thermal tab should have an appropriately designed PCB copper area, and thermal vias can be used where the board stackup permits them.

For higher power levels, the complete thermal path from silicon to PCB to ambient needs to be analyzed.

IRF640NSTRLPBF Compared With IRF640NPBF

This is one of the most useful comparisons for someone searching the part number.

Both belong to the IRF640N family and share the basic 200 V N-channel MOSFET characteristics.

The major difference is the package.

IRF640NPBF is the TO-220 version.

IRF640NSTRLPBF is the D2PAK version.

If an existing PCB is designed for D2PAK, changing to TO-220 is not a drop-in substitution.

Likewise, if a repair board was designed for a through-hole TO-220 device, a D2PAK replacement may require a completely different mounting arrangement.

Therefore, the package suffix is critical when sourcing the correct component.

What the LPBF Suffix Tells the Buyer

The complete part number should be retained when searching for the device.

The LPBF designation is part of the ordering code associated with the lead-free version and packaging configuration.

The STR portion distinguishes the surface-mount D2PAK configuration from the other IRF640N package variants.

This is why searching only for IRF640N can produce several physically different products.

For a production BOM, the complete IRF640NSTRLPBF should be used as the purchasing reference.

Is IRF640NSTRLPBF a Logic Level MOSFET

This is another point worth clarifying.

IRF640NSTRLPBF should not be selected simply because its gate threshold can fall in the few-volt range.

Its published RDS(on) specification is based on 10 V gate drive.

If a controller provides only 3.3 V at the gate, the designer should not assume that the MOSFET will achieve the specified 150 mΩ maximum on-resistance.

A dedicated gate driver or an appropriate higher gate-drive voltage may therefore be necessary depending on the circuit.

This is particularly important when the MOSFET is expected to carry substantial current.

When IRF640NSTRLPBF Is a Poor Choice

The part's 200 V rating can make it look attractive for many high-voltage designs, but there are situations where a different MOSFET would be better.

A high-frequency converter may benefit from a device with substantially lower gate charge.

A low-voltage battery system may benefit from a much lower RDS(on).

A 3.3 V gate-drive system may need a MOSFET specifically optimized for low gate voltage.

A high-power design may require a package with a different thermal structure.

In other words, the right question is not "Is IRF640NSTRLPBF a good MOSFET?"

The better question is whether its combination of voltage, conduction loss, switching behavior and package matches the specific power stage.

Sourcing IRF640NSTRLPBF

For buyers, the exact MPN is particularly important because the IRF640N family contains multiple package variants.

Infineon currently lists IRF640NSTRLPBF as an active product, with D2PAK packaging and tape-and-reel delivery.

When comparing suppliers, buyers should verify the complete manufacturer part number rather than accepting a listing that simply says IRF640N.

For production procurement, it is also useful to check packaging quantity, traceability, manufacturer status and delivery schedule.

Finding IRF640NSTRLPBF Suppliers

ElecSuppliers can be used as a supplier discovery source when buyers search for the exact IRF640NSTRLPBF part number.

This is particularly useful for a component such as this because the base family name can lead to several package variants.

Searching the complete MPN keeps the procurement process focused on the D2PAK version required by the design.

For a production application, the supplier should still be evaluated for authenticity, traceability and availability before the order is finalized.

The Practical Meaning of IRF640NSTRLPBF

IRF640NSTRLPBF is best understood as a 200 V power-switching MOSFET designed around a conventional 10 V gate-drive condition and packaged for surface-mount power applications.

Its 18 A current rating, 150 mΩ maximum RDS(on), 200 V drain-source rating, 175°C maximum junction temperature and D2PAK package define a particular design space.

The part becomes especially interesting when a design needs more voltage headroom than a low-voltage MOSFET can provide while still requiring a PCB-mounted power transistor.

For engineers, the important specifications are not isolated numbers but the relationship between them.

For buyers, the most important detail is simpler: IRF640NSTRLPBF is the D2PAK version of the IRF640N family, so the complete part number should be preserved when sourcing or replacing the device.