Fairchild FDS8870 service manual

tm

FDS8870
N-Channel PowerTrench

30V, 18A, 4.2mΩ

®

MOSFET

FDS8870 N-Channel PowerTrench

April 2007

Features

 r

 r

 High performance trench technology for extremely low

 Low gate charge

 High power and current handling capability

 RoHS Compliant

Branding Dash

DS(on)

DS(on)

r

DS(on)

= 4.2mΩ, V

= 4.9mΩ, V

= 10V, ID = 18A

GS

= 4.5V, ID = 17A

GS

General Description

This N-Channel MOSFET has been designed specifically to
improve the overall efficiency of DC/DC converters using
either synchronous or conventional switching PWM
controllers. It has been optimized for low gate charge, low
r

and fast switching speed.

DS(on)

Applications

 DC/DC converters

5

4

®

MOSFET

1

2

3

4

SO-8

©2007 Fairchild Semiconductor Corporation
FDS8870 Rev. B

5

6

7

8

www.fairchildsemi.com1

3

2

1

FDS8870 N-Channel PowerTrench

MOSFET Maximum Ratings T

= 25°C unless otherwise noted

A

Symbol Parameter Ratings Units

V

DSS

V

GS

Drain to Source Voltage 30 V

Gate to Source Voltage ±20 V

Drain Current

I

D

Continuous (TA = 25oC, VGS = 10V, R

Continuous (TA = 25oC, VGS = 4.5V, R

= 50oC/W)

θJA

= 50oC/W) 17 A

θJA

18 A

Pulsed 134 A

E

AS

P

D

TJ, T

STG

Single Pulse Avalanche Energy (Note 1) 420 mJ

Power dissipation 2.5 W

Derate above 25oC 20 mW/oC

Operating and Storage Temperature -55 to 150

Thermal Characteristics

R

θJC

R

θJA

R

θJA

Thermal Resistance, Junction to Case (Note 2) 25

Thermal Resistance, Junction to Ambient (Note 2a) 50

Thermal Resistance, Junction to Ambient (Note 2b) 125

Package Marking and Ordering Information

Device Marking Device Package Reel Size Tape W i dt h Quantity

FDS8870 FDS8870 SO-8 330mm 12mm 2500 units

Electrical Characteristics T

Symbol Parameter Test Conditions Min Typ Max Units

= 25°C unless otherwise noted

J

o

C/W

o

C/W

o

C/W

o

C

®

MOSFET

Off Characteristics

B

I

DSS

I

GSS

VDSS

Drain to Source Breakdown Voltage ID = 250µA, VGS = 0V 30 - - V

Zero Gate Voltage Drain Current

Gate to Source Leakage Current VGS = ±20V - - ±100 nA

On Characteristics

V

GS(TH)

r

DS(on)

Gate to Source Threshold Voltage VGS = VDS, ID = 250µA 1.2 - 2.5 V

Drain to Source On Resistance

Dynamic Characteristics

C

ISS

C

OSS

C

RSS

R

G

Q

g(TOT)

Q

g(5)

Q

g(TH)

Q

gs

Q

gs2

Q

gd

Input Capacitance

Output Capacitance - 900 - pF

Reverse Transfer Capacitance - 450 - pF

Gate Resistance VGS = 0.5V, f = 1MHz 0.5 2.0 3.5 Ω

Total Gate Charge at 10V VGS = 0V to 10V

Total Gate Charge at 5V VGS = 0V to 5V - 45 62 nC

Threshold Gate Charge VGS = 0V to 1V - 4.6 6.0 nC

Gate to Source Gate Charge - 11 - nC

Gate Charge Threshold to Plateau - 6.4 - nC

Gate to Drain “Miller” Charge - 15 - nC

VDS = 24V - - 1

VGS = 0V TJ = 150oC - - 250

ID = 18A, VGS = 10V - 3.5 4.2

ID = 17A, VGS = 4.5V - 3.9 4.9

ID = 18A, VGS = 10V,
TJ = 150oC

VDS = 15V, VGS = 0V,

- 5.5 7.2

- 4615 - pF

f = 1MHz

- 85 11 2 nC

VDD = 15V
ID = 18A
Ig = 1.0mA

µA

mΩ

©2007 Fairchild Semiconductor Corporation
FDS8870 Rev. B

www.fairchildsemi.com2

Switching Characteristics (V

t

ON

t

d(ON)

t

r

t

d(OFF)

t

f

t

OFF

Turn-On Time

Turn-On Delay Time - 9 - ns

Rise Time - 48 - ns

Turn-Off Delay Time - 60 - ns

Fall Time - 21 - ns

Turn-Off Time - - 122 ns

GS

= 10V)

- - 86 ns

VDD = 15V, ID = 18A
VGS = 10V, RGS = 3.3Ω

Drain-Source Diode Characteristics

I

= 18A - - 1.25 V

V

SD

t

rr

Q

RR

Notes:

1: Starting TJ = 25°C, L = 1mH, IAS = 29A, VDD = 30V, VGS = 10V.
2: R

θJA

drain pins. R

a) 50°C/W when mounted on a 1in

b) 125°C/W when mounted on a minimum pad.

Source to Drain Diode Voltage

Reverse Recovery Time ISD = 18A, dISD/dt = 100A/µs - - 37 ns

Reverse Recovered Charge ISD = 18A, dISD/dt = 100A/µs - - 22 nC

is the sum of the junction-to-case and case-to-ambient thermal resistance where the case thermal reference is defined as the solder mounting surface of the

is guaranteed by design while R

θJC

2

pad of 2 oz copper.

is determined by the user’s board design.

θJA

SD

ISD = 2.1A - - 1.0 V

FDS8870 N-Channel PowerTrench

®

MOSFET

©2007 Fairchild Semiconductor Corporation
FDS8870 Rev. B

www.fairchildsemi.com3

FDS8870 N-Channel PowerTrench

Typical Characteristics T

1.2

1.0

0.8

0.6

0.4

0.2

POWER DISSIPATION MULTIPLIER

0

0255075100 150

TA, AMBIENT TEMPERATURE (oC)

= 25°C unless otherwise noted

J

Figure 1. Normalized Power Dissipation vs

Ambient Temperature

2

1

DUTY CYCLE-DESCENDING ORDER

D = 0.5

0.1

θJA

Z

0.01

0.2

0.1

0.05

0.02

0.01

125

20

15

VGS = 10V

R

θJA

VGS = 4.5V

=50oC/W

TA, AMBIENT TEMPERATURE (oC)

10

, DRAIN CURRENT (A)

D

I

5

0

25 50 75 100 125 150

Figure 2. Maximum Continuous Drain Current vs

Ambient Temperature

®

MOSFET

NORMALIZED THERMAL

IMPEDANCE,

0.001

0.0001

3000

1000

100

10

, PEAK TRANSIENT POWER (W)

(PK)

P

0.5

SINGLE PULSE

R

= 125oC/W

θJA

-4

10

-3

10

-2

10

t, RECTANGULAR PULSE DURATION (s)

-1

10

0

10

1

10

2

10

3

10

Figure 3. Normalized Maximum Transient Thermal Impedance

VGS = 10V

1

-4

10

-3

10

-2

10

-1

10

t, PULSE WIDTH (s)

0

10

1

10

SINGLE PULSE

R

= 125oC/W

θJA

T

= 25oC

A

2

10

3

10

Figure 4. Single Pulse Maximum Power Dissipation

©2007 Fairchild Semiconductor Corporation
FDS8870 Rev. B

www.fairchildsemi.com4