AN11158

Understanding power MOSFET data sheet parameters
Rev. 6.0 — 6 July 2020

application note

Document information
Information

Content

Keywords

MOSFET, data sheet, parameters, SOA

Abstract

This application note describes the content of power MOSFET data sheet parameters.

AN11158

Nexperia

Understanding power MOSFET data sheet parameters

1. Introduction
This application note explains the parameters and diagrams given in a Nexperia Semiconductors
Power MOSFET data sheet. The goal is to help an engineer decide what device is most suitable fora particular application.
It is important to pay attention to the conditions for which the parameters are listed, as theycan vary between suppliers. These conditions can affect the values of the parameters making
it difficult to choose between different suppliers. Throughout this document, the data sheet for
BUK7Y3R5-40H is used as an example. BUK7Y3R5-40H is an automotive-qualified part in a
SOT669 (LFPAK56) package, with a voltage rating of 40 V.
The layout of this data sheet is representative of the general arrangement of Nexperia power
MOSFET data sheets.
Nexperia Power MOSFETs are designed with particular applications in mind. For example,
switching charge is minimized where switching losses dominate, whereas on-resistance isminimized where conductive losses dominate.

2. Data sheet technical sections
Nexperia power MOSFET data sheets begin with an overview of the device, giving the designer the
key information regarding device suitability. The overview consists of:•••General description, describing the technology used, the package and relevant qualifications,e.g. AEC-Q101
Features and benefits, listing important features of the MOSFET and the benefit they offer.
Applications, listing the applications for which the MOSFET is particularity suited.

The product overview is followed by these technical sections:
•
•
•
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•

AN11158

application note

Quick reference data
Pinning information
Ordering information
Limiting values
Thermal characteristics
Electrical characteristics
Package outline

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AN11158

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Understanding power MOSFET data sheet parameters2.1. Quick reference data
The quick reference data table contains more detailed information and the key parameters
for the intended application. An example of a quick reference data table is shown in
Table 1 “Quick reference data”.
Table 1. Quick reference data
SymbolParameter

Conditions

Min

Typ

Max

Unit

VDS

drain-source voltage

25 °C ≤ Tj ≤ 175 °C

-

-

40

V

ID

drain current

VGS = 10 V; Tmb = 25 °C; Fig. 1

-

-

120

A

Ptot

total power dissipation

Tmb = 25 °C; Fig. 2

-

-

115

W

VGS = 10 V; ID = 20 A; Tj = 25 °C

2

2.9

3.5

mΩ

ID = 20 A; VDS = 44 V; VGS = 10 V

-

6

15

nC

IS = 25 A; dIS/dt = -100 A/μs;VGS = 0 V;
VDS = 20 V

-

16

-

nC

[1]

Static characteristics
RDSon

drain-source on-state
resistance

Dynamic characteristics
QGD

gate-drain charge

Source-drain diodeQr[1]

recovered charge

120 A continuous current has been successfully demonstrated during application tests. Practically the current will be limited by PCB,
thermal design and operating temperature.

The general format for describing a parameter is to provide the official symbol and then the correct
parameter name. Any relevant conditions and information are listed after the parameter names.
The values and units of the values are entered in the remaining columns. Generally, measurement
methods are as described in IEC 60747-8.
The quick reference data parameters are described in more detail in the characteristics sectionof the data sheet. The following list is an introduction to some of the key symbols together with adescription of the parameter each represents:
•
•
•
•

•
•

AN11158

application note

VDS - the maximum voltage between drain and source that the device is guaranteed to blockin the off state. This section of the data sheet deals with the most commonly used temperature
range, as opposed to the full temperature range of the device.
ID - the maximum continuous current the device can carry with the mounting base held
continuously at 25 °C with the device fully on. In the example provided in Table 1, ID requires a
VGS of 10 V.
Ptot - the maximum continuous power the device can dissipate with the mounting base held
continuously at 25 °C.
RDSon (drain-source on state resistance) - the typical and maximum resistance of the device
in the on-state under the conditions described. RDSon varies greatly with both Tj and the gatesource voltage (VGS). Graphs are provided in the data sheet to assist in determining RDSon
under various conditions.
QGD (gate-drain charge) - an important switching parameter that relates to switching loss, alongwith QGS and QG(tot). QGD is inversely proportional to RDSon, therefore choosing an appropriatebalance between RDSon and QGD is critical for optimal circuit performance.
Qr (recovered charge) – the total amount of charge recovered from the anti-parallel diode when
it is switched from its conducting state to its reverse biased state under controlled conditions.
Qr is an important factor involved in voltage spiking when interacting with external inductances
and an important consideration when investigating EMC and efficiency. Generally the higher the
Qr value the larger the voltage and current spikes at switch off leading to longer damping times.
Nexperia includes stored charge Qs as well as output charge Qoss in its stated value for Qr suchthat Qr = Qs + Qoss.

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AN11158

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Understanding power MOSFET data sheet parameters2.2. Pinning information
This section describes the internal connections and general layout of the device. Note that thesymbol is for an enhancement mode n-channel MOSFET with the source and body tied together,and a parallel diode between the source and drain. The parallel diode is known as the body diodeand is inherent in power MOSFETs. N-channel power MOSFETs have the body diode between
drain and source, as shown in Table 2.
Table 2. Pinning information
Pin
SymbolDescription

Simplified outline

1

S

source2Ssource3Ssource

4

G

gate

mb

D

mounting base; connected
to drainGraphic symbolDmbGmbb076S

1 2 3 4

LFPAK56; PowerSO8 (SOT669)

2.3. Ordering information
The ordering section provides information on how to order the device. The package version anddecription are given as well as any commonly used package name.

2.3.1. Marking
Depending on the device package, the data sheet may include a marking section. This provides
the marking code which is printed onto the device during manufacter, (else the device name will be
printed).

2.4. Limiting values
The limiting values table provides the range of operating conditions allowed for the MOSFET.
The conditions are defined in accordance with the absolute maximum rating system (IEC 60134).
Operation outside of these conditions is not guaranteed, so it is recommended that these values
are not exceeded. Doing so runs the risk of immediate device failure or reduced lifetime of the
MOSFET. The avalanche ruggedness conditions, when given, describe the limited conditions forwhich the VDS rating can be exceeded.
To calculate how the limiting values change with temperature, they are read together with thederating curves provided.
The limiting values table for the BUK7Y3R5-40H is given as an example of a standard limiting
values table, in Table 3.
Table 3. Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).
SymbolParameter

Conditions

Min

Max

Unit

VDS

drain-source voltage

25 °C ≤ Tj ≤ 175 °C

-

40

V

VGS

gate-source voltage

-10

20

V

Ptot

total power dissipation

Tmb = 25 °C;

-

115

W

ID

drain current

VGS = 10 V; Tmb = 25 °C; Fig. 1

[1]

-

120

A

VGS = 10 V; Tmb = 100 °C; Fig. 2

[1]

-

93

A

-

526

A

-55

175

°C

IDM

peak drain current

Tstg

storage temperature

AN11158

application notepulsed; tp ≤ 10 µs; Tmb = 25 °C

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AN11158

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Understanding power MOSFET data sheet parameters
SymbolParameter

Tjjunction temperature

Conditions

Min

Max

Unit

-55

175

°C

-

120

A

-

526

A

-

45

mJ

Source-drain diodeIS

source current

Tmb = 25 °C

ISM

peak source current

pulsed; tp ≤ 10 µs; T mb = 25 °C[1]

Avalanche ruggedness
EDS(AL)S

[1]
[2]
[3]

non-repetitive drainID = 120 A; Vsup ≤ 40 V; RGS = 50 Ω;source avalanche energy VGS = 10 V; Tj(init) = 25 °C; unclamped;
Fig. 3[2] [3]120 A continuous current has been successfully demonstrated during application tests. Practically the current will be limited by PCB,
thermal design and operating temperature.
Single-pulse avalanche rating limited by maximum junction temperature of 175 °C.
Refer to application note AN10273 for further information.

•

•

•
•

•
•

•
•
•

AN11158

application note

VDS (drain-source voltage) - the maximum voltage the device is guaranteed to block between
the drain and source terminals in the off-state for the specified temperature range. For the
BUK7Y3R5-40H, the temperature range is from +25 °C to +175 °C. For operation below 25 °C,
the VDS rating reduces due to the positive temperature coefficient of avalanche breakdown.
This is covered in Section 2.4.1 of this document.
VGS (gate-source voltage) - the maximum voltage the device is specified to block between
the gate and source terminals. Some Nexperia data sheets specify different values for DC
and pulsed VGS. In these cases the DC value is a constant gate voltage over the lifetime ofthe device at the maximum Tj, whilst the higher-value pulsed-rating is for a shorter, specified
accumulated pulse duration at the maximum specified Tj.
Gate-oxide lifetime (refer to AN90001) reduces with increasing temperature and/or increasinggate voltage. This means that VGS lifetimes or ratings quoted for lower junction temperaturesare significantly greater than if specified at higher temperatures. This can be important whencomparing data sheet values from different manufacturers.
VDGR (drain-gate voltage) is typically the same value as the VDS rating. This parameter
appears in the data sheets of older devices but is not quoted for newer devices such as in the
BUK7Y3R5-40H data sheet.
ID (drain current) - the maximum continuous current the device is allowed to carry under theconditions described. This value can be related to either package construction, or the maximum
current that would result in the maximum Tj. As such it depends on an assumed mounting basetemperature (Tmb), the thermal resistance (Rth) of the device, and its RDSon at maximum Tj.
Note that some suppliers quote the "theoretical" silicon limit, while indicating the package
limited value in the characteristic curves.
IDM (peak drain current) is the maximum drain current the device is allowed to carry for a pulseof 10 μs or less.
Ptot (total power dissipation) is the maximum allowed continuous power dissipation for a device
with a mounting base at 25 °C. The power dissipation is calculated as that which would takethe device to the maximum allowed junction temperature while keeping the mounting base at
25 °C. In reality, it is difficult to keep the mounting base at this temperature while dissipating
the 105 W that is the calculated power dissipation for the BUK7Y3R5-40H. In other words, Ptot
indicates how good the thermal conductivity of the device is, and its maximum allowed junction
temperature.
Note that some other semiconductor vendors quote performance when mounted on acopper PCB usually 1 inch square. In practice, this information is rather meaningless as thesemiconductor vendor has no control over how the device is cooled. See AN10874 - LFPAKMOSFET thermal design guide. AN10874 describes different techniques that can be usedduring the design phase to ensure that the PCB layout provides optimum thermal performance.
Tstg (storage temperature) is the temperature range in which the device can be stored without
affecting its reliability. Long term storage should be in an inert atmosphere to prevent device
degradation, for example, by tarnishing of the metal leads.
Tj (junction temperature) is the operational temperature range of the device. Typically, Tj is thesame as the storage temperature. Outside of this range, device parameters are outside therange of the data sheet and device lifetime is reduced.
IS (source current) - the maximum continuous current of the MOSFET body diode, which isbriefly discussed in Section 2.2. The same considerations apply as for ID.

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AN11158

Nexperia

Understanding power MOSFET data sheet parameters•••

ISM (peak source current) - the maximum current pulse that the MOSFET body diode isguaranteed to carry. The same considerations apply as for IDM.
EDS(AL)S (non-repetitive drain-source avalanche energy) - the maximum allowed single
overvoltage energy pulse under the conditions specified. For this example, the conditions are
the maximum continuous drain current allowed for a mounting base temperature of 25 °C. The
avalanche energy allowed is the energy pulse that would raise the device temperature from
25 °C to its maximum allowed Tj, while the mounting base temperature is held at 25 °C.
The avalanche energy is specified for the maximum continuous drain current. Some vendors
specify the avalanche energy for a different current and higher inductive load, which canincrease the apparent avalanche energy for an inferior performance. An example is given withthe derating curve as described in Section 2.4.3 of this document.
EDS(AL)R (repetitive drain-source avalanche energy) - the maximum amount of energy allowedin each avalanche event when more than one avalanche event occurs. The thermal constraints
imposed for repeated avalanche operation is given by curve 3 of Fig. 3 in Section 2.4.3 ofthis document. There are also the standard thermal requirements in addition to the energy
requirements for repetitive avalanche events. These requirements are assessed with thethermal characteristic curves as described in Section 2.5. Avalanche performance is covered indetail in application note AN10273.
This parameter is only listed on Nexperia data sheets where the repetitive avalanche capability
has been assessed. It is not shown in Nexperia data sheets where it has not been assessed,
for example non-automotive MOSFETs.

2.4.1. Derating curves
The derating curves are provided immediately after the tabulated limiting value data, and help thedesigner calculate how the limits change with temperature.

2.4.1.1. Continuous drain current
The following procedure serves as an example to calculate the maximum continuous drain current
for the BUK7Y3R5-40H. Assume an application with a mounting base temperature Tmb of 75 °C.
Refer to the graph depicted in Fig. 1 which depicts the continuous drain current as a function ofmounting base temperature.
Fig. 1 shows that for a Tmb of 75 °C, the maximum continuous drain current has reduced from 120
A, listed at 25 °C, to 105 A, see Equation (1) and Equation (2) below.
The maximum current at any Tmb, is the current that increases Tj to the maximum allowed2
temperature (175 °C). P = I x RDSon represents the power dissipation at Tj, where the RDSon usedis the maximum value for the maximum Tj. Therefore, the allowed current is proportional to thesquare root of the allowed power dissipation.
The power dissipation allowed for a given Tmb is proportional to the allowed temperature increase.
This means that the derating curve shown, is based on the following equations:Tj − Tmb
ID2(Tmb ) ∝ −Tj − 25 °C(1)Tj − Tmb
ID (Tmb ) = ID (25 °C) × −Tj − 25 °C(2)

At the maximum allowed junction temperature of 175 °C, this current has decreased to zero.

AN11158

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Understanding power MOSFET data sheet parameters
aaa-026228

150
ID
(A)
125
(1)

100
75
50
25
0

0

25

50

75

100

125

150 175
Tmb (°C)

200

VGS ≥ 10 V
(1) 120 A continuous current has been successfully demonstrated during application
tests. Practically the current will be limited by PCB, thermal design and operating
temperature.
Fig. 1.

Continuous drain current as a function of mounting base temperature

2.4.2. Power dissipation
Power dissipation varies with different temperatures. However, in this case, the power dissipation
curve is normalized. The allowed power is presented as a percentage of the allowed power
dissipation at 25 °C, as opposed to an absolute value.

Example:By observing the curve in Fig. 2, the allowed power dissipation for a Tmb of 75 °C is approximately
66 % of that allowed at 25 °C. The graphic data in Fig. 2, shows the maximum continuous power
dissipation (Ptot) at 25 °C is 105 W.
This means that the maximum power dissipation allowed at 75 °C, is 66 % of 105 W which is 70 W.
Equation (3) is the equation to calculate power dissipation:

Tj − Tmb
Ptot (Tmb ) = Ptot (25 °C) × −Tj − 25 °C(3)Where Tj = Tj(max), usually 175 °C.

AN11158

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AN11158

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Understanding power MOSFET data sheet parameters
03na19

120
Pder
(%)
80

40

0

Fig. 2.

0

50

100

150

Tmb (°C)

200

Normalized total power dissipation as a function of mounting base temperature

The curves provided in Fig. 1 and Fig. 2 are read in conjunction with the limiting values tables.
The information extracted, assists in calculating the maximum current allowed and the power
dissipation with respect to temperature.

2.4.3. Avalanche ruggedness
Avalanche ruggedness is covered in detail in AN10273.

IAL
(A)

aaa-026229

103

maximum avalanche pulse
120 A for 14.5 μs
avalanche pulse
40 A for 150 μs

102

(1)

10

(2)

(3)

1

10-1
10-3

Fig. 3.

10-2

10-1

1
tAL (ms)

10

Avalanche current as a function of avalanche period

A simple example for the BUK7Y3R5-40H, using the information in AN10273, is extracted from thelimiting values Table 3:With ID = 120 A, Vsup ≤ 40 V, RGS = 50 Ω, VGS = 10 V and Tj(init) = 25 °C unclamped, the maximum
EDS(AL)S is 45 mJ.
An avalanche event has a triangular pulse shape, so the average power is calculated as(0.5 × VDS × IDS).
AN10273 states that the assumed breakdown voltage is 130 % of the rated voltage, in the case of
the BUK7Y3R5-40H this is 52 V (40 V x 1.3).
Fig. 3 shows a maximum current of 120 A at 25 °C (the limiting values Table 3 confirms this value).
The time for the maximum avalanche energy can be read from Fig. 3 as 14.5 μs.

AN11158

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AN11158

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Understanding power MOSFET data sheet parameters
This means that the maximum avalanche energy allowed is:
0.5 × (40 V × 1.3) × 120 A × 14.5 μs = 45.24 mJ.
However the limit value quoted in Table 5 of the data sheet is rounded to 45 mJ.
If a competitor quotes avalanche energy at 40 A, the graph shows that the avalanche
time for the BUK7Y3R5-40H has increased to 150 μs. The avalanche energy is now
0.5 × (40 V × 1.3) × 40 A × 150 μs = 156 mJ, which is much higher than data sheet limiting value.
Ruggedness events lie outside the Safe Operating Area (SOA).

2.4.4. Safe Operating Area (SOA)The Safe Operating Area (SOA) curves are some of the most important on the data sheet.

ID(A)

aaa-026230

103
Limit RDSon= VDS / ID

102

tp = 10 us
100 us10

1Spirito effect (uneven die heating) occurs when a longer
pulse causes a larger current to develop and is evident
by a gradient change in the SOA curve

DC
1 ms
10 ms
100 ms10-1
10-1

Fig. 4.

1

10

VDS (V)102

Safe operating area; continuous and peak drain currents as a function of drain-source voltage
The SOA curves show the voltage allowed, the current and time envelope of operation for the
MOSFET. These values are for an initial Tmb of 25 °C and a single current pulse. This is a complex
subject which is further discussed in the appendix (Section 3.1).

2.5. Thermal characteristics
This section describes the thermal impedance as a function of pulse duration for different duty
cycles. This information is required to determine the temperature that the silicon reaches underparticular operating conditions, and whether it is within the guaranteed operation envelope.
The thermal characteristics are shown in Table 4. The thermal impedance changes with pulse
length because the MOSFET is made from different materials. For shorter durations, the thermal
capacity is more important, while for longer pulses, the thermal resistance is more important.
The thermal characteristics are used to check whether particular power loading pulses above
the DC limit would take Tj above its safe maximum limit. Repetitive avalanche pulses must be
considered in addition to the constraints specific to avalanche and repetitive avalanche events.
Table 4. Thermal characteristics
SymbolParameter

Conditions

Min

Typ

Max

Unit

Rth(j-mb)

Fig. 5

-

1.18

1.3

K/W

AN11158

application notethermal resistance fromjunction to mounting base

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AN11158

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Understanding power MOSFET data sheet parameters
aaa-026231

10
Zth(j-mb)(K/W)
1

δ = 0.5
0.2

10-1

0.1
0.05
0.02

single shot

P

δ=

10-2
tp
10-3
10-6

Fig. 5.

10-5

10-4

10-3

10-2

10-1

tp
T

t
T
tp (s)

1

Transient thermal impedance from junction to mounting base as a function of pulse duration.
Thermal resistance (Rth) and thermal impedance (Zth) are related because the thermal resistanceis the steady-state measure of how the device blocks heat flow. Thermal impedance is how thedevice responds to transient thermal events. It involves different thermal capacities of parts of thedevice and the thermal resistances between these parts. Under DC conditions, Zth is equal to Rth.
Equation (4) represents the temperature rise for a particular power dissipation:

ΔTj = |Zth(j - mb)| × Power(4)

A worked example is discussed in the appendix (Section 3.1.2).

AN11158

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AN11158

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Understanding power MOSFET data sheet parameters2.6. Electrical characteristics
This section is used to determine whether the MOSFET would be suitable in a particularapplication. This section differs from the previous two sections that are used to determine whether
the MOSFET would survive within the application. The examples in this section are taken from thedata sheet for the BUK7Y3R5-40H unless otherwise stated.

2.6.1. Static characteristics
The static characteristics are the first set of parameters listed in this section and an example isshown in Table 5:
Table 5. Static characteristics
SymbolParameter

Conditions

Min

Typ

Max

Unit

V(BR)DSS

ID = 250 µA; VGS = 0 V; Tj = 25 °C

40

42.7

-

V

ID = 250 µA; VGS = 0 V; Tj = -40 °C

-

40.1

-

V

ID = 250 µA; VGS = 0 V; Tj = -55 °C

36

39.7

-

V

ID = 1 mA; VDS =VGS ; Tj = 25 °C; Fig. 6;
Fig. 7

2.4

3

3.6

V

ID = 1 mA; VDS =VGS ; Tj = -55 °C; Fig. 6

-

-

4.3

V

ID = 1 mA; VDS =V GS ; Tj = 175 °C;
Fig. 61--V

VDS = 40 V; VGS = 0 V; Tj = 25 °C

-

0.03

1

µA

VDS = 16 V; VGS = 0 V; Tj = 125 °C

-

1

10

µA

VDS = 40 V; V GS = 0 V; Tj = 175 °C

-

37

500

µA

VGS = 20 V; VDS = 0 V; Tj = 25 °C

-

2

100

nA

V GS = -10 V; VDS = 0 V; Tj = 25 °C

-

2

100

nA

V GS = 10 V; ID = 25 A; Tj = 25 °C

2

2.9

3.5

mΩ

V GS = 10 V; ID = 25 A; Tj = 105 °C;
Fig. 9

2.7

4.1

5.2

mΩ

V GS = 10 V; ID = 25 A; Tj = 125 °C;
Fig. 9

2.9

4.5

5.6

mΩ

V GS = 10 V; ID = 25 A; Tj = 175 °C;
Fig. 9

3.4

5.4

6.7

mΩ

f = 1 MHz; Tj = 25 °C

0.32

0.8

2

Ω

VGS(th)

IDSS

IGSS
RDSon

RG

drain-source
breakdown voltage

gate-source thresholdvoltagedrain leakage current

gate leakage current
drain-source on-state
resistancegate resistance••

AN11158

application note

VBR(DSS) (drain-source breakdown voltage) - an expansion of the parameter listed andexplained in Section 2.4. This section lists the minimum voltage the device is guaranteed
to block between the drain and source terminals in the off-state over the entire MOSFET
temperature range. The temperature range is from -55 °C to +175 °C. The current between thedrain and the source terminals of the BUK7Y3R5-40H when testing V(BR)DSS is 250 µA at thetemperatures stated. V(BR)DSS is 40 V or less if the device is cooler than +25 °C and 40 V if thedevice is between +25 °C and +175 °C.
The effect of temperature on the off-state characteristics is twofold. The leakage current
increases with temperature, turning the device on. Competing against the leakage current
increase, the breakdown voltage also increases with temperature.
VGS(th) (gate-source threshold voltage) is important for determining the on-state and the offstate of the MOSFET. VGS(th) is defined where VDS = VGS, although it is sometimes quoted
for a fixed VDS (e.g. 10 V). Note that the definition of the threshold voltage for a particularcurrent where the gate and drain are shorted together, can differ from examples in textbooks.
The parameter in textbooks describes a change in the physical state of the MOSFET and isindependent of the MOSFET chip size. The parameter used in the data sheet is for a specified
current and is dependent on the chip size, as the current flow is proportional to the chip area.

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AN11158

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Understanding power MOSFET data sheet parameters
The threshold voltage in the data sheet is defined in a way that is best for routine measurement,
but not how the actual device would typically be used. Consequently, the graphs provided inFig. 6 and Fig. 7.

VGS(th)(V)

aaa-018139

5

aaa-018138

10-1

ID
(A)

10-2

4
Max
3

Min

10-3

Typ

Typ

Max

10-4

2
Min

10-5

1

0
-60

-30

0

30

60

90

120 150
Tj (°C)180

10-6

ID = 1 mA; VDS = VGS
Fig. 6.

0

1

2

3

4
VGS (V)5

Tj = 25 °C; VDS = 5 V

Gate-source threshold voltage as a function ofjunction temperature

Fig. 7.

Subthreshold drain current as a function ofgate-source voltage

Fig. 6 shows the variation in the threshold voltage for the typical and limit devices over the rated
temperature range. All the MOSFETs are guaranteed to have a threshold voltage between thelines.
Consequently, for the BUK7Y3R5-40H at 65 °C, if VDS and VGS are both less than 2 V, all devices
carry less than 1 mA. Also, all devices carry more than 1 mA if VDS and VGS are both greater than
4 V. At 175 °C, the lower limit has fallen to 1 V, while the upper limit has fallen to 2.4 V. The lower
limit is usually more important as it determines when the device is guaranteed to be turned off, andthe gate driver performance an application needs.
Fig. 7 shows how the device turns on around this threshold voltage. For the BUK7Y3R5-40H, thecurrent increases 100,000 times for an increase in gate voltage of less than 1 V. An example isgiven for the situation when the drain-source voltage is fixed at 5 V.
•••

IDSS (drain leakage current) guarantees the maximum leakage current that the device passes at
its maximum rated drain-source voltage(40V in this case) during the off-state. It is important tonote how much higher IDSS is at high temperature, which is the worst case.
IGSS (gate leakage current) guarantees the maximum leakage current through the gate of
the MOSFET. The IGSS is important when calculating how much current is required to keep
the device turned on. Because it is a leakage current through an insulator, this current is
independent of temperature, unlike IDSS.
RDSon (drain-source on-state resistance) is one of the most important parameters. The previous
parameters guarantee how the device functions when it is off, how it turns off and what leakage
currents could be expected. These factors are important when battery capacity is an issue inthe application.

RDSon is a measure of how good a closed-switch the MOSFET is, when turned-on. It is a key factor
in determining the power loss and efficiency of a circuit containing a MOSFET. The on-resistance2
RDSon x ID gives the power dissipated in the MOSFET when it is turned fully on. Power MOSFETs
are capable of carrying tens or hundreds of amps in the on-state.
Power dissipated in the MOSFET makes the die temperature rise above that of its mounting base.
Also when the MOSFET die temperature increases, its RDSon increases proportionally. Maximum
recommended junction temperature is 175 °C (for all Nexperia packaged MOSFETs).
Using the BUK7Y3R5-40H data sheet as an example:
Rth(j-mb) temperature rise per Watt between junction (die) and mounting base = 1.3 K/W (1.3 °C/W).

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Maximum power dissipation for temperature rise of 150 K (Tmb = 25 °C, Tj = 175 °C) =150 / 1.3 = 115.38 W, note data sheet Ptot is rounded to 115 W.
Maximum RDSon at a die temperature (Tj) of 175 °C = 6.7 mΩ.
2

Therefore, at steady state with Tmb = 25 °C and Tj = 175 °C; P = 115.38 W = Imax × RDSon(175 °C).
Therefore:(5)

P(max)175 °C
115.38 W
Imax = − = −RDSon 175 °C
0.0067 Ω= 131.23 A (rounded down to 120 A in the data sheet).

Note this value appears on the curve for ID vs Tmb in Fig. 1 but only 120 A is claimed in the data
sheet. Practically, limitations are placed on MOSFET performance due to PCB, thermal design andoperating temperature, which will all act together to raise the mounting base temperature.
Fig. 8 shows the dependency of RDSon on the gate-source voltage for a standard level MOSFET(e.g. BUK7Y12-55B); the red dashed line shows the curve for a hot device and is indicative of how
the dependency changes at a high temperature.
aaa-002470

35
RDSon
(mΩ)
28

21
Hot RDSon

14

7

0

4

8

12

16

VGS (V)

20

This diagram is for illustrative purposes only and not to be taken as an indication of hot
RDSon performance for any device.
Fig. 8.

Drain-source on-state resistance as a function of gate-source voltage at 25 °C andhigh temperature

If an application requires good RDSon performance for lower gate-source voltages, then MOSFETs
are made with lower threshold voltages, e.g. the BUK9Y12-55B (logic level MOSFET). However,the lower threshold voltage of such a device means that it has a lower headroom for its off-state athigh temperature. This lower headroom often means that a device with a higher threshold voltage
is needed.
Fig. 9 shows how the ratio of RDSon to RDSon at 25 °C typically varies with junction temperature for
BUK7Y3R5-40H.

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Understanding power MOSFET data sheet parametersaaaa-018451

2

1.6

1.2

0.8

0.4

0
-60

-30

0

30

60

90

120 150
Tj (°C)

180

RDSon
ɑ=−
RDSon 25 °C
Fig. 9.

Normalized drain-source on-state resistance factor as a function of junction
temperature

RG (gate resistance) is the internal series resistance presented to the gate pin. In most applications
an external “gate stopper” resistance of a larger value is employed to mitigate gate oscillation and,dependent on value chosen, decrease output slew rate.

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2.6.2. Dynamic characteristics
The dynamic characteristics determine the switching performance of the device. Several of theseparameters are highly dependent on the measurement conditions. Consequently, understandthe dynamic characteristics before comparing data sheets from suppliers with different standard
conditions. Table 6 is a sample dynamic characteristics table.
Table 6. Dynamic characteristics
List of constants and limitations relating to the table i.e. voltages, currents and temperatures
SymbolParameter

Conditions

Min

Typ

Max

Unit

QG(tot)total gate charge

ID = 25 A; VDS = 32 V; VGS = 10 V;

-

31

53

nC

QGS

gate-source charge

-

10

15

nC

QGD

gate-drain charge

-

6

15

nC

Ciss

input capacitance

-

2294

3441

pF

Coss

output capacitance

-

682

954

pF

Crss

reverse transfer
capacitance

-

112

247

pF

td(on)

turn-on delay time

-

10

-

ns

tr

rise time

-

8

-

ns

td(off)turn-off delay time

-

19

-

ns

tf

fall time

-

9

-

ns

VDS = 25 V; VGS = 0 V; f = 1 MHz;
Tj = 25 °C;

VDS = 30 V; RL = 1.2 Ω; VGS = 10 V;
RG(ext) = 5 Ω

Source-drain diodeVSD

source-drain voltage

IS = 25 A; VGS = 0 V; Tj = 25 °C;

-

0.8

1.2

V

trr

reverse recovery time

-

25

-

ns

Qr

recovered charge

IS = 25 A; dIS/dt = -100 V/μs;
VGS = 20 V;

-

16

-

nC

2.6.2.1. Gate charge
QG(tot), QGS, and QGD are all parameters from the same gate charge curve. They describe howmuch gate charge the MOSFET requires to switch, for certain conditions. This is particularly
important in high frequency switching applications. Much of the power loss occurs during switching,when there are significant voltage and current changes simultaneously between the drain, gate
and source. In the blocking state, there are significant voltages but negligible currents. In the full-on
state, there are significant currents and small voltages
The gate charge parameters are dependent on the threshold voltage and the switching dynamics
as well as the load that is being switched. There is a difference between a resistive load and an
inductive load.
An example of a gate charge curve is shown in Fig. 10:

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VG
QG(tot)QGS (plateau)

QGD
VGS(th)VD
QGS(th)QGS (plateau)

QG(tot)ID
QGS (plateau)

QGS(th)aaa-002471

Fig. 10. Gate charge curve also showing drain-source currents and voltages
Due to capacitance variation with voltage and current, it is better to look at the gate charge datarather than the capacitance data when determining switching performance. This is especially true
if the gate-driver circuit for the MOSFET is limited to a particular current, and a rapid switch is
required.
The gate charge curve describes what happens to a MOSFET which has a drain supply limited toa particular current and voltage. The operation of the test circuit means that during the gate charge
curve, the MOSFET is provided with either a constant voltage or a constant current.
During this time, the drain-source voltage begins to fall because the increased charge on the
MOSFET allows easier conduction. Consequently, although the gate-source voltage is constant,the drain-gate voltage is falling.
Eventually the capacitance stops increasing and any further increases in gate charge increase
the gate-source voltage. This characteristic is sometimes referred to as the "Miller plateau" as it
refers to the time during which the so-called Miller capacitance increases. The Miller plateau is also
known as the gate-drain charge (QGD).
During this period, there are significant currents and voltages between the drain and source, so
QGD is important when determining switching losses.
Once the end of the Miller plateau is reached, the gate-source voltage increases again, but with alarger capacitance than before QGS had been reached. The gradient of the gate charge curve isless above the Miller plateau.
The gate-charge parameters are highly dependent on the measurement conditions. Different
suppliers often quote their gate-charge parameters for different conditions, demanding care whencomparing gate charge parameters from different sources.
Higher currents lead to higher values of gate-source charge because the plateau voltage is also
higher. Higher drain-source voltages, lead to higher values of gate-drain charge and total gatecharge, as the plateau increases.
The drain-source currents and voltages during the gate charge switching period are shown in
Fig. 10.

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If the MOSFET starts in the off state (VGS = 0 V), an increase in charge on the gate initially leads toan increase in the gate-source voltage. In this mode, a constant voltage (VDS) is supplied between
the source and drain.
When the gate-source voltage reaches the threshold voltage for the limiting current at that drainsource voltage, the capacitance of the MOSFET increases and the gate-voltage stays constant.
This is known as the plateau voltage and the onset charge is referred to as QGS. The higher thecurrent is, the higher the plateau voltage (see Fig. 11). This relates to the transfer characteristic,
see Fig. 15. The transfer curve shows the dependency of drain current on gate voltage. The higher
the voltage on the gate the higher the charge applied, (Q = C × V), hence making it the easier for
the MOSFET to conduct.
aaa-002472

VGS
(V)

reduced VDS
QGS

Qtot

QGD

reduced IDS

Vplateau

QG (nC)

Fig. 11. Features of gate charge curve

2.6.2.2. Capacitances
Capacitance characteristics are generally less useful than the gate charge parameters, for thereasons already discussed. However, they are still listed on data sheets. The three capacitancesthat are normally listed are as follows:•••

Ciss (input capacitance) is the capacitance between the gate and the other two terminals(source and drain).
Coss (output capacitance) is the capacitance between the drain and the other two terminals(gate and source).
Crss (reverse transfer capacitance) is the capacitance between the drain and the gate.

See Fig. 13.
Semiconductor capacitances generally depend on both voltage and the frequency of thecapacitance measurement. Although it is difficult to compare capacitances measured under
different conditions, many suppliers specify a measurement frequency of 1 MHz. Consequently,
the capacitances vary with drain-source voltage (see Fig. 12). However, the capacitances also varywith gate-source voltage, which is why the gradients in the gate-charge curve vary for different
voltages (see Fig. 10).
The relationship between charge, voltage and capacitance in the gate charge curve is:
ΔQ = ΔC x ΔV. For different gradients at different gate voltages, the capacitance changes
significantly with gate-source voltage.

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aaa-026238

104
C
(pF)

CGD
NMOS

Ciss
103

CDS

CGS

Coss
aaa-022333

Ciss = CGS + CGD
Coss = CDS + CGD
Crss = CGD

Crss

102

Fig. 13. MOSFET capacitance parameters
10
10-1

1

10

VDS (V)102

VGS = 0 V; f = 1 MHz
Fig. 12. Capacitances as a function of drain source
voltage

2.6.2.3. Switching times
Most manufacturers quote resistive load switching times. However, extreme care is needed whencomparing data from different manufacturers, as they are highly dependent on the resistance of thegate drive circuit used for the test and in the case of logic level devices, the gate voltage applied.
In devices for fast switching applications, the gate resistance of the MOSFET is often quoted as
capacitive time constants which are equally dependent on resistance and capacitance.

2.6.2.4. Diode characteristics
The diode characteristics are important if the MOSFET is being used in the so-called "third
quadrant". The third quadrant is a typical arrangement where the MOSFET replaces a diode to
reduce the voltage drop from the inherent diode forward voltage drop. In such a situation, there isalways a small time period when the MOSFET parasitic diode is conducting before the MOSFET
turns on. For such applications, the diode switching parameters are important. In addition, diodereverse recovery (Fig. 14) contributes to the power losses as well as oscillation and voltage spikes,
which can cause EMC concerns.

ID
(A)

trr
dI/dt

ta

tb

0
0.25 IRM
dIR/dtIRM

t (s)trr = ta + tb
Fig. 14. Reverse recovery waveform definitions

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2.6.2.5. Transfer characteristics
Fig. 15 shows the transfer characteristics of the MOSFET which indicate the theoretical draincurrent that can be handled by the device as a result of applied gate to source voltage. The graphshows the temperature dependency of the characteristic. The convergent point indicates where
the current is dependent only on gate voltage and not temperature hence the MOSFET’s Zero
Temperature Coefficient point I_ZTC. Gate charge test current and plateau voltage (refer to Fig. 10)
can be directly read from the transfer curve.
aaa-026234

200

ID
(A)

160

120

80

175C

40

0

25°C
Tj = -55°C
0

1

2

3

4

5
VGS (V)6

VDS = 12 V
Fig. 15. Transfer characteristics; drain current as a function of gate-source voltage; typicalvalues

2.7. Package outline
This section describes the package outline dimensions and tolerances.

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3. Appendices3.1. Safe Operating Area (SOA) curves
To highlight the key features, Fig. 16 provides an idealized SOA curve for a hypothetical MOSFET.
Data for a hypothetical MOSFET for a single pulse length, is shown to highlight the region where it
deviates from the ideal curve.
aaa-002473

102

(2)

IDS
(A)

(3)
(1)

10

(5)

(4)

1

10-1

1.
2.
3.
4.
5.

1

10

102

VDS (V)103

RDSon limit (VDS/IDS is constant)
Maximum pulsed drain current (IDS is constant)
Maximum pulsed power dissipation (VDS x IDS is constant)
Maximum allowed voltage (VDS is constant)Linear mode derating - a departure from the ideal behavior shown in (3) due tooperation within a regime of positive feedback, and potential thermal runaway

Fig. 16. Idealized SOA curve at a single time pulse for hypothetical MOSFETThe dashed line (5) is to emphasize where the curve deviates from the ideal. In reality, there is asingle curve with a change of gradient where the linear mode derating becomes important.

RDSon limit
RDSon is region (1) of the graph and Equation (6) represents the limiting line:

VDS− ≤ RDSon(max) (175 °C)
IDS

(6)

The limit is when the MOSFET is fully on and acting as a closed switch with a resistance that is no
greater than the hot RDSon.

Constant current region
The constant current region is region (2) of the graph. It is the maximum pulsed drain current,
which is limited by the device manufacturer (for example, the wire-bonds within the package).

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Maximum power dissipation (linear mode) limit
In this region, the MOSFET is acting as a (gate) voltage-controlled current source. This meansthat there are significant voltages and currents applied simultaneously, leading to significant power
dissipation. Line (3) shows the idealized curve, whereas the dotted line (5) shows where it deviatesfrom the ideal.
The limiting factor for the SOA curve in region (5), is the heating applied during a rectangularcurrent and voltage pulse. Even in the ideal situation, this curve depends on the transient thermal
impedance of the MOSFET, which is covered in Section 2.5.
The transient thermal impedance varies with the pulse length. This is due to the different materials
in the MOSFET having different thermal resistances and capacities. The differences createa thermal equivalent to an RC network from the junction (where the heat is generated) to themounting base. Equation (7) is the calculation used to determine the ideal curve in this region.
(7)

Tj(max) − Tmb
P = ID × VDS = − = ConstantZth(j−mb)

The ideal situation accurately describes the situation for sufficiently high current densities.
However, it is overly optimistic for low current-densities, i.e. towards the bottom right of region (3).
Low current densities and high voltages can lead to thermal runaway in the linear mode operation.
Thermal runaway is discussed in the following section.

Thermal runaway in linear mode
Power MOSFETs are often considered to be immune to thermal runaway due to the temperature
coefficient of resistance, which means that as temperature rises, current falls.
This is only true for MOSFETs that are fully on (i.e. in region 1), but it is not the whole story.
When a MOSFET is turned on, there are two competing effects that determine how its current
behaves with increasing temperature. As the temperature rises, the threshold voltage falls. The
MOSFET is effectively turned on more strongly, thereby increasing the current. In opposition, theresistance of the silicon increases with increasing temperature, thereby reducing the current. The
resultant effect for a constant drain-source voltage, is shown in Fig. 17. This situation occurs when
the gate-source voltage of a MOSFET is being used to control the current, or when the MOSFET isswitched sufficiently slowly.
ID(A)

negative temp.
coefficient

25 °C

175 °CZTC point

positive temp.
coefficient

VGS (V)
aaa-002474

Fig. 17. Transfer characteristics for a hypothetical MOSFET, showing regions of positive
and negative temperature coefficient

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The resistance increase dominates at high currents, meaning that localized heating leads to lower
currents. The threshold-voltage drop dominates at low currents, meaning that localized heating
lowers the threshold voltage. This condition effectively turns on the device more, leading to higher
currents and a risk of thermal runaway.
Consequently, for a given VDS, there is a critical current below which there is a positive-feedback
regime and a subsequent risk of thermal runaway. Above this critical current, there is negative
feedback and thermal stability. This critical current is known as the Zero Temperature Coefficient(ZTC) point.
This effect reduces the SOA performance for low currents and high drain-source voltages. The
constant power line must be reduced as shown in region (5). For short switching events, this effectis insignificant. However, as the duration of the switching event becomes longer, for example toreduce electromagnetic interference, the effect becomes more important and potentially hazardous.

Voltage-limited region
The device is limited by its breakdown voltage VDS which is shown in region (4). The quickreference data provides values for VDS at temperatures of 25 °C and above. In the hypothetical
MOSFET shown in Fig. 16, the rating is 100 V. For the BUK7Y3R5-40H, the voltage is 40 V.

3.1.1. Safe operating area for temperatures above 25 °C
When reading from the SOA curves there are two main considerations:
1. The mounting base temperature is at 25 °C
2. The MOSFET is exposed to a rectangular power pulse
The SOA curves indicate the pulse power required to raise the MOSFET junction temperature,
Tj, from 25 °C to its maximum rating of 175 °C, Tj(max).The assumption being Tj is at the mounting
base temperature Tmb = 25 °C when power dissipation begins.
Under DC conditions, where a product has been operating for some time (thermally soaked), Tj will
be close to the mounting base temperature, Tmb.
Under high power short duration pulse conditions Tj, can be much greater than Tmb.
A reduction in MOSFET power handling capability results if the initial Tmb > 25 °C, so it is importantto establish an accurate temperature for Tmb to determine Tj which is non-trivial activity.
The majority of automotive power applications thermally link the MOSFET mounting base via
the PCB footprint and an electrically isolating barrier to a metallic mass (e.g. product housing) toact as a heatsink. Heatsink temperature Ths is in turn thermally linked to the product’s ambient
temperature, Tamb, which may be 85 °C for in-cabin (inside the driver compartment) or 105 °C forunder the hood (near and around the engine). In some automotive applications where, for example,
the housing is mounted directly to the power train the customer may specify a temperature directlyon the heatsink where Ths ≥ 105 °C.
Unless the offset relationship Tmb > Tamb is well defined by thermal flow modelling and test
verification, the designer can only estimate Tmb.
It is important to remember that in a product which has been operating for some time (thermallysoaked) MOSFETs which have similar thermal linkages to the same heatsink will have a similar
Tmb, whether the MOSFET is switched on or switched off.
Calculation to determine the rise in die temperature above mounting base temperature is given
below, see Equation (8).

Tj(rise) = Tj(max) − Tj(mb) = Ppeak ⋅ Zth(t)(8)

Where:
Ppeak is the peak power, as this is a rectangular pulsed waveform.

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Zth(t) is the thermal impedance value between junction and mounting base for a pulse of t
seconds duration.
Note: In DC applications, (where the MOSFET is not pulsed), use Rth(j-mb) instead of Zth(j-mb).
Generally, for pulses above 100 ms, Zth is indistinguishable from Rth.
Equation 8 assumes heating is uniformly spread across the whole die. A combination of higher
VDS with lower IDS and pulse durations ≥ 100 μs can cause hot spotting (uneven heating) to occur
known as the Spirito effect. Refer to TN00008 Section 5 for further details.

3.1.1.1. Example calculations
Calculate the max DC IDS for BUK7Y3R5-40H, with VDS = 10 V at 25 °C
Rewrite Equation (10) to bring out IDS as the main subject (Power is substituted by IDS × VDS).
Since Equation (10) is being used for a DC situation, the Zth(t) parameter used in Equation (8) andEquation (9) is replaced by the Rth steady state condition.

Tj(rise) = IDS × VDS × Zth(t)(9)

Tj(rise)− = IDS
VDS × Rth(10)

175 °C − 25°C
− = 11.3 A
10 V × 1.3 K/W(11)When making these calculations always refer to the Safe Operating Area Curve for the device. The
SOA curve for the BUK7Y3R5-40H is Fig. 4 which can be found in Section 2.4.4. The intersectionof ID = 11.3 A and VDS = 10 V occurs above the DC curve and therefore this condition exceeds
device capability. The reason being heat distribution is non-uniform within the die. In other words
hot spotting is present, otherwise known as the Spirito effect.
The BUK7Y3R5-40H SOA curve shows for a DC condition the Spirito effect for this device (thepoint at which a gradient change occurs) is evident at VDS = 0.94 V for ID= 120 A. As ID reduces,
the allowable VDS increases and by ID = 11.3 A the maximum permissible VDS = 4.4V. Thermal
consideration are discussed further in Section 3.1.2.

3.1.2. Example using the SOA curve and thermal characteristics
Consider the following application during linear mode operation:
•
•
•
•
•

Ipulse = 20 A
Vpulse = 30 V
f = 2 kHztpulse = 100 μs
Tamb = 25 °C

3.1.2.1. Calculation steps
The SOA curve (Fig. 4) is initially checked to see whether any single pulse would cause a problem.
Observing the SOA curve, it can be seen that the 20 A, 30 V pulse lies between the 100 μs and1 ms lines. This indicates that the pulse lies within acceptable limits.
The duty cycle for the pulses is now calculated using a frequency of 2 kHz for 100 μs pulses.
These values give a duty cycle of 0.2. The Zth curve (Fig. 5) indicates that for 100 μs, the line withthe duty cycle (δ) has a transient thermal impedance of 0.35 K/W.
The power dissipation for the square pulse is 20 A × 30 V, which equals 600 W.
Using Equation (8), the temperature rise for the 100 μs pulse is calculated as being 600 W × 0.35
K/W, which equals 210 K. With a starting temperature of 25 °C, the temperature rise results in a

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finishing temperature of 235 °C. As the MOSFET junction temperature must not exceed 175 °C, the
MOSFET is not suitable for this application.
If the application requires a single pulse, then the curve shows that the transient thermal
impedance for a 100 μs pulse is 0.12 K/W. As a result, the temperature rise is 600 W × 0.12 K/W
which equals 72 K. The finishing temperature is then 97 °C for a starting temperature of 25 °C. The
device is able to withstand this, thereby confirming what the SOA curve already indicated.

3.1.2.2. Derating for higher starting temperatures
The example Safe Operating Area calculations were performed for a mounting base temperatureof 25 °C. At higher mounting base temperatures, the SOA curves must be de-rated, as theallowed temperature rise in the junction is reduced. The allowed power of the pulse is reduced
proportionally to the reduced temperature rise. For example, with a mounting base temperature of
25 °C, the allowed temperature rise is 150 °C. At 100 °C, the allowed temperature rise is half ofthat (75 °C). The allowed power is half of that allowed at 25 °C.
The allowed drain current is de-rated while the allowed drain-source voltage is maintained.
The ID derating of the SOA curve at 100 °C is shown in Fig. 18.

ID(A)

aaa-002475

103

8 V, 30 A at Tmb = 100 °C
is above the 1 ms curve - outside SOA

Limit RDSon = VDS / ID
102

30 A at 100 °C

tp = 10 us

10DC
0.5 A at 100 °C

8 V, 30 A at Tmb = 25 °C
is below the 1 ms curve - inside the SOA

1

1 ms
10 ms
100 ms0.05 A at 100 °C

10-1
10-1

1

10

VDS (V)102

Tmb = 25 °C; IDM is a single pulse
Fig. 18. SOA curve showing derating from Tmb = 25 °C to Tmb = 100 °C

Example:Is a 1 ms pulse of 30 A and 8 V allowed at 100 °C?
See Fig. 18, the intersection of the blue lines of the rectangular power pulse ID = 30 A * VDS = 8 V
below the 1 ms curve indicates that the device can safely handle this pulse with Tmb = 25 °C .
Power handling capability halves with Tmb = 100 °C. In Fig. 18 the red text shows ID at 100 °C ishalf the value at 25 °C.
The intersection of the red lines of the rectangular power pulse ID = 30 A * VDS = 8 V above the 1
ms curve indicates the device cannot handle this pulse at Tmb = 100 °C.

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Understanding power MOSFET data sheet parameters

4. References
1. The Impact of Trench Depth on the Reliability of Repetitively Avalanched Low-Voltage DiscretePower Trench nMOSFETs - Alatise et al, IEE Electron Device Letters, Volume 31, No7, July
2010, pages 713-715.
2. Semiconductor Devices - Physics and Technology S.M.Sze, 1985, John Wiley and Sons.
3. Nexperia application note AN10273 - Power MOSFET single-shot and repetitive avalancheruggedness rating.
4. Nexperia application note AN10874 - LFPAK MOSFET thermal design guide.
5. Nexperia application note AN90001 - Designing in MOSFETs for safe and reliable gate-drive
operation.
6. Nexperia technical note TN00008 - Power MOSFET frequently asked questions and answers.

5. Abbreviations
Table 7. Abbreviations
AcronymDescription

AEC-Q101

Automotive Electronics Council Quality System (applicable to
MOSFETs)IEC

International Electrotechnical Commission

MOSFET

Metal-Oxide Semiconductor Field-Effect Transistor

PCB

Printed Circuit Board [1]SOA

Safe Operating Area

ZTC

Zero temperature coefficient[1]

For the purposes of this application note; FR-4 a flame retardent composite of woven fibreglass and epoxy
resin binder.

6. Revision history
Table 8. Revision history
Revision
Date
numberDescription

6.0

20200706

Section 3.1.2.2 updated.

5.0

20200406

Document updated to reference the BUK7Y3R5-40H data sheet; other minor editorialchanges.

4.0

20140204

Equation (2) corrected

3.0

20130107

Figure cross reference correction and temperature qualifier added on page 10

2.020120816

Second release

1.0

20120416

Initial release

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List of Tables
Table 1. Quick reference data..............................................3
Table 2. Pinning information................................................ 4
Table 3. Limiting values....................................................... 4
Table 4. Thermal characteristics.......................................... 9
Table 5. Static characteristics............................................ 11
Table 6. Dynamic characteristics....................................... 15
Table 7. Abbreviations........................................................25
Table 8. Revision history....................................................25

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List of Figures
Fig. 1. Continuous drain current as a function ofmounting base temperature................................................. 7
Fig. 2. Normalized total power dissipation as afunction of mounting base temperature............................... 8
Fig. 3. Avalanche current as a function of avalanche period8
Fig. 4. Safe operating area; continuous and peak draincurrents as a function of drain-source voltage..................... 9
Fig. 5. Transient thermal impedance from junction tomounting base as a function of pulse duration.................. 10
Fig. 6. Gate-source threshold voltage as a function ofjunction temperature.......................................................... 12
Fig. 7. Subthreshold drain current as a function ofgate-source voltage............................................................12
Fig. 8. Drain-source on-state resistance as a functionof gate-source voltage at 25 °C and high temperature.......13
Fig. 9. Normalized drain-source on-state resistancefactor as a function of junction temperature.......................14
Fig. 10. Gate charge curve also showing drain-source
currents and voltages.........................................................16
Fig. 11. Features of gate charge curve.............................. 17
Fig. 12. Capacitances as a function of drain source
voltage................................................................................ 18
Fig. 13. MOSFET capacitance parameters........................18
Fig. 14. Reverse recovery waveform definitions................ 18
Fig. 15. Transfer characteristics; drain current as afunction of gate-source voltage; typical values.................. 19
Fig. 16. Idealized SOA curve at a single time pulse for
hypothetical MOSFET........................................................ 20
Fig. 17. Transfer characteristics for a hypothetical
MOSFET, showing regions of positive and negative
temperature coefficient.......................................................21
Fig. 18. SOA curve showing derating from Tmb = 25
°C to Tmb = 100 °C...........................................................24

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Contents
1. Introduction................................................................... 2
2. Data sheet technical sections..................................... 2
2.1. Quick reference data................................................... 3
2.2. Pinning information...................................................... 4
2.3. Ordering information.................................................... 4
2.3.1. Marking..................................................................... 4
2.4. Limiting values.............................................................4
2.4.1. Derating curves........................................................ 6
2.4.2. Power dissipation......................................................7
2.4.3. Avalanche ruggedness............................................. 8
2.4.4. Safe Operating Area (SOA)......................................92.5. Thermal characteristics................................................92.6. Electrical characteristics............................................ 11
2.6.1. Static characteristics...............................................112.6.2. Dynamic characteristics.......................................... 15
2.7. Package outline......................................................... 19
3. Appendices................................................................. 20
3.1. Safe Operating Area (SOA) curves........................... 20
3.1.1. Safe operating area for temperatures above 25 °C.22
3.1.2. Example using the SOA curve and thermal
characteristics.....................................................................23
4. References.................................................................. 25
5. Abbreviations.............................................................. 25
6. Revision history..........................................................25
7. Legal information........................................................26© Nexperia B.V. 2020. All rights reserved

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Date of release: 6 July 2020

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