©2008 Fairchild Semiconductor Corporation FDS6680AS Re v B2(X)
FDS6680AS
30V N-Channel PowerTrench® SyncFET™
General Description
The FDS6680AS is designed to replace a single SO-8
MOSFET and Schottky diode in synchronous DC:DC
power supplies. This 30V MOSFET is designed to
maximize power conversion efficiency, providing a low
RDS(ON) and low gate charge. The FDS6680AS
includes an integrated Schottky diode using Fairchild’s
monolithic SyncFET technology. The performance of
the FDS6680AS as the low-side switch in a
synchronous rectifier is indistinguishable from the
performance of the FDS6680 in parallel with a Schottky
diode.
Applications
• DC/DC converter
• Low side notebooks
Features
• 11.5 A, 30 V. RDS(ON) max= 10.0 mΩ @ VGS = 10 V
RDS(ON) max= 12.5 mΩ @ VGS = 4.5 V
• Includes SyncFET Schottky body diode
• Low gate charge (22nC typical)
• High performance trench technology for extremely low
RDS(ON) and fast switching
• High power and current handling capability
S
D
S
S
SO-8
D
D
D
G
4
3
2
1
5
6
7
8
Absolute Maximum Ratings TA=25oC unless otherwise noted
Symbol Parameter Ratings Units
VDSS Drain-Source Voltage 30 V
VGSS Gate-Source Voltage ±20 V
ID Drain Current – Continuous (Note 1a) 11.5 A
– Pulsed 50
Power Dissipation for Single Operation (Note 1a) 2.5
(Note 1b) 1.2
PD
(Note 1c) 1
W
TJ, TSTG Operating and Storage Junction Temperature Range –55 to +150 °C
Thermal Characteristics
RθJA Thermal Resistance, Junction-to-Ambient (Note 1a) 50 °C/W
RθJC Thermal Resistance, Junction-to-Case (Note 1) 25 °C/W
Package Marking and Ordering Information
Device Marking Device Reel Size Tape width Quantity
FDS6680AS FDS6680AS 13’’ 12mm 2500 units
FDS6680AS 30V N-Channel PowerTrench® SyncFET™
tm
May 2008
FDS6680AS Re v B2(X)
Electrical Characteristics TA = 25°C unless otherwise noted
Symbol Parameter Test Conditions Min Typ Max Units
Off Characteristics
BVDSS Drain–Source Breakdown Voltage VGS = 0 V, ID = 1 mA 30 V
∆BVDSS
∆TJ Breakdown Voltage Temperature
Coefficient ID = 10 mA, Referenced to 25°C 26
mV/°C
IDSS Zero Gate Voltage Drain Current VDS = 24 V, VGS = 0 V 500 µA
IGSS Gate–Body Leakage VGS = ±20 V, VDS = 0 V
±100 nA
On Characteristics (Note 2)
VGS(th) Gate Threshold Voltage VDS = VGS, ID = 1 mA 1 1.5 3 V
∆VGS(th)
∆TJ Gate Threshold Voltage
Temperature Coefficient ID = 10 mA, Referenced to 25°C
–4
mV/°C
RDS(on) Static Drain–Source
On–Resistance VGS = 10 V, ID = 11.5 A
VGS = 4.5 V, ID = 9.5 A
VGS=10 V, ID =11.5A, TJ=125°C
8.4
10.3
12.3
10.0
12.5
15.5
mΩ
ID(on) On–State Drain Current VGS = 10 V, VDS = 5 V 50 A
gFS Forward Transconductance VDS = 15 V, ID = 11.5 A 48 S
Dynamic Characteristics
Ciss Input Capacitance 1240 pF
Coss Output Capacitance 350 pF
Crss Reverse Transfer Capacitance
VDS = 15 V, V GS = 0 V,
f = 1.0 MHz 120 pF
RG Gate Resistance VGS = 15 mV, f = 1.0 MHz 1.4 Ω
Switching Characteristics (Note 2)
td(on) Turn–On Delay Time 9 18 ns
tr Turn–On Rise Time 5 10 ns
td(off) Turn–Off Delay Time 27 42 ns
tf Turn–Off Fall Time
VDS = 15 V, ID = 1 A,
VGS = 10 V, RGEN = 6 Ω
11 21 ns
td(on) Turn–On Delay Time 11 20 ns
tr Turn–On Rise Time 12 22 ns
td(off) Turn–Off Delay Time 18 32 ns
tf Turn–Off Fall Time
VDS = 15 V, ID = 1 A,
VGS = 4.5 V, RGEN = 6 Ω
11 20 ns
Qg(TOT) Total Gate Charge at Vgs=10V 22 30 nC
Qg Total Gate Charge at Vgs=5V 12 16 nC
Qgs Gate–Source Charge 3.5 nC
Qgd Gate–Drain Charge
VDD = 15 V, ID = 11.5 A,
3.4 nC
FDS6680AS 30V N-Channel PowerTrench® SyncFET™
FDS6680AS Re v B2(X)
Electrical Characteristics TA = 25°C unless otherwise noted
Symbol Parameter Test Conditions Min Typ Max Unit
Drain–Source Diode Characteristics and Maximum Ratings
IS Maximum Continuous Drain–Source Diode Forward Current 3.5 A
VSD Drain–Source Diode Forward
Voltage VGS = 0 V, IS = 3.5 A (Note 2)
VGS = 0 V, IS = 7 A (Note 2) 0.5
0.6 0.7 V
Trr Diode Reverse Recovery Time IF = 11.5A, 18 nS
Qrr Diode Reverse Recovery Charge diF/dt = 300 A/µs (Note 3) 12 nC
Notes:
1. RθJA 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
drain pins. RθJC is guaranteed by design while RθCA is determined by the user's board design.
a) 50°/W when
mounted on a 1 in2
pad of 2 oz copper
b) 105°/W when
mounted on a .04 in2
pad of 2 oz copper
c) 125°/W when mounted on a
minimum pad.
Scale 1 : 1 on letter size paper
2. Pulse Test: Pulse Width < 300µs, Duty Cycle < 2.0%
3. See “SyncFET Schottky body diode characteristics” below.
FDS6680AS 30V N-Channel PowerTrench® SyncFET™
FDS6680AS Re v B2(X)
Typical Characteristics
0
10
20
30
40
50
0 0.4 0.8 1.2 1.6 2
V
DS
, DRAIN-SOURCE VOLTAGE (V)
I
D
, DRAIN CURRENT (A)
4.5V
4.0V
3.5V
3.0V
V
GS
= 10V
6.0V
2.5V
0.8
1
1.2
1.4
1.6
1.8
2
0 1020304050
I
D
, DRAIN CURRENT (A)
R
DS(ON)
, NORMALIZED
DRAIN-SOURCE ON-RESISTANCE
V
GS
= 3.0V
4.5V
6.0V 10.0V
4.0V
3.5V
5.0V
Figure 1. On-Region Characteristics. Figure 2. On-Resistance Variation with
Drain Current and Gate Voltage.
0.6
0.8
1
1.2
1.4
-50 -25 0 25 50 75 100
T
J
, JUNCTION TEMPERATURE (
o
C)
R
DS(ON)
, NORMALIZED
DRAIN-SOU RC E ON-R E SI S TA NC E
I
D
= 11.5A
V
GS
= 10V
0
0.01
0.02
0.03
0.04
0.05
246810
V
GS
, GATE TO SOURCE VOLTAGE (V)
R
DS(ON)
, ON-RESISTANCE (OHM)
I
D
= 6A
T
A
= 125
o
C
T
A
= 25
o
C
Figure 3. On-Resistance Va riation with
Temperature. Figure 4. On-Resistance Va riation with
Gate-to-Source Voltage.
0
10
20
30
40
50
11.522.533.54
V
GS
, GATE TO SOURCE VOLT AGE (V)
I
D
, DRAIN CURRENT (A)
T
A
= 125
o
C
25
o
C
V
DS
= 5V
-55
o
C
0.0001
0.001
0.01
0.1
1
10
0 0.2 0.4 0.6 0.8
V
SD
, BODY DIODE F ORWARD VOLTAGE (V)
I
S
, REVERSE DR AIN CURRENT (A)
T
A
= 125
o
C
25
o
C
-55
o
C
V
GS
= 0V
Figure 5. Transfer Characteristics. Figure 6. Body Diode Forward Voltage Variation
with Source Current and Temperature.
FDS6680AS 30V N-Channel PowerTrench® SyncFET™
FDS6680AS Re v B2(X)
Typical Characteristics (continued)
0
2
4
6
8
10
0 5 10 15 20 25
Q
g
, GATE CHARGE (nC)
V
GS
, GATE-SOURCE VOL TA GE (V)
I
D
=11.5A
V
DS
= 10V
15V
20V
0
300
600
900
1200
1500
1800
0 5 10 15 20 25 30
V
DS
, DRAIN TO SOURCE VOLTAGE (V)
CAPACITANCE (pF)
C
iss
C
rss
C
oss
f = 1MHz
V
GS
= 0 V
Figure 7. Gate Charge Characteristics. Figure 8. Capacitance Cha racteristics.
0.01
0.1
1
10
100
1000
0.1 1 10 100
V
DS
, DRAIN-SOURCE VOLT AGE (V)
I
D
, DRAIN CURRE NT (A)
DC10s1s 100ms
100
µ
s
R
DS(ON)
LIMIT
V
GS
= 10V
SINGLE PULSE
R
θ
JA
= 125
o
C/W
T
A
= 25
o
C
10ms 1ms
0
10
20
30
40
50
0.01 0.1 1 10 100 1000
t
1
, TIME (sec)
P(pk), PEAK TRANSIENT POWER (W)
SINGLE PULSE
R
θ
JA
= 125°C/W
T
A
= 25°C
Figure 9. Maximum Safe Operating Area. Figure 10. Single Pulse Maximum
Power Dissipation.
0.001
0.01
0.1
1
0.0001 0.001 0.01 0.1 1 10 100 1000
t
1
, TIME (sec)
r(t), NORMALIZED EFFECTIVE
TRANSIENT THERMAL RESISTANCE
R
θJA
(t) = r( t) * R
θJA
R
θJA
= 125 °C/W
T
J
- T
A
= P * R
θJA
(t)
Duty Cycle, D = t
1
/ t
2
P(pk)
t
1
t
2
SINGLE PULSE
0.01
0.02
0.05
0.1
0.2
D = 0.5
Figure 11. Transient Thermal Response Curve.
Thermal characterization performed using the conditions described in Note 1c.
Transient thermal response will change depending on the circuit board design.
FDS6680AS 30V N-Channel PowerTrench® SyncFET™
FDS6680AS Re v B2(X)
Typical Characteristics (continued)
SyncFET Schottky Body Diode
Characteristics
Fairchild’s SyncFET process embeds a Schottky diode in
parallel with PowerTrench MOSFET. This diode exhibits
similar characteristics to a discrete external Schottky
diode in parallel with a MOSFET. Figure 12 shows the
reverse recovery characteristic of the FDS6680AS.
Figure 12. FDS6680AS SyncFET body diode
reverse reco very characteristic.
For comparison purposes, Figure 13 shows the reverse
recovery characteristics of the body diode of an
equivalent size MOSFET produced without SyncFET
(FDS6680).
Current: 3A/div
10nS/div
0
Figure 13. Non-SyncFET (FDS6680) body
diode reverse recovery characteristic.
Schottky barrier diodes exhibit significant leakage at high
temperature and high reverse voltage. This will increase
the power in the device.
0.000001
0.00001
0.0001
0.001
0.01
0.1
0 5 10 15 20 25 30
V
DS
, REVERSE VOLTAGE (V)
I
DSS
, REVERSE LEAKAGE CURRENT (A)
T
A
= 125
o
C
T
A
= 25
o
C
T
A
= 100
o
C
Figure 14. SyncFET body diode reverse
leakage versus drain-source voltage and
temperature.
3A/DIV
10nS/DIV
FDS6680AS 30V N-Channel PowerTrench® SyncFET™
FDS6680AS Re v B2(X)
Typical Characteristics
VDS L
Figure 15. Unclamped Inductive Load Test
Circuit Figure 16. Unclamped Inductive
Waveforms
Figure 20. Switching Time Waveforms
RGE DUT
VGS
IAS 0.01Ω
VDD
+
-
tp
0V
vary tP to obtain
required peak IAS
VGS
tAV
tP
IAS VDS
VDD
BVDSS
Figure 19. Switching Time Test
Circuit
VDS RL
RGEN DUT VDD
VGS
Pulse Width ≤ 1µs
Duty Cycle ≤ 0.1%
VGS
+
-
trtf
td(ON) td(OFF
)
tON tOFF
Pulse Width
10%
10%
90%
10%
90%
50%
90%
50%
0V
0V
VGS
VDS
Figure 17. Gate Charge Test Circuit Figure 18. Gate Charge Waveform
VGS QGS QGD
QG(TOT)
10V
Charge, (nC)
DUT
VDD
VGS
Ig(REF
+
-
+
-
Same type as
Drain Current
1µF
10µF
10V 50kΩ
FDS6680AS 30V N-Channel PowerTrench® SyncFET™
Rev. I34
TRADEMARKS
The following includes registered and unregistered trademarks and service marks, owned by Fairchild Semiconductor and/or its global
subsidianries, and is not intended to be an exhaustive list of all such trademarks.
* EZSWITCH™ and FlashWriter® are trademarks of System General Corporation, used under license by Fairchild Semiconductor.
DISCLAIMER
FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS
HEREIN TO IMPROVE RELIABILITY, FUNCTION, OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE
APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER
ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. THESE SPECIFICATIONS DO NOT EXPAND THE TERMS OF FAIRCHILD’S
WORLDWIDE TERMS AND CONDITIONS, SPECIFICALLY THE WARRANTY THEREIN, WHICH COVERS THESE PRODUCTS.
LIFE SUPPORT POLICY
FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR
SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF FAIRCHILD SEMICONDUCTOR CORPORATION.
As used herein:
1. Life support devices or systems are devices or systems which,
(a) are intended for surgical implant into the body or (b)
support or sustain life, and (c) whose failure to perform when
properly used in accordance with instructions for use provided
in the labeling, can be reasonably expected to result in a
significant injury of the user.
2. A critical component in any component of a life support,
device, or system whose failure to perform can be reasonably
expected to cause the failure of the life support device or
system, or to affect its safety or effectiveness.
PRODUCT STATUS DEFINITIONS
Definition of Terms
ACEx®
Build it Now™
CorePLUS™
CorePOWER™
CROSSVOLT™
CTL™
Current Transfer Logic™
EcoSPARK®
EfficentMax™
EZSWITCH™ *
™
Fairchild®
Fairchild Semiconductor®
FACT Quiet Series™
FACT®
FAST®
FastvCore™
FlashWriter® *
FPS™
F-PFS™
FRFET®
Global Power ResourceSM
Green FPS™
Green FPS™ e-Series™
GTO™
IntelliMAX™
ISOPLANAR™
MegaBuck™
MICROCOUPLER™
MicroFET™
MicroPak™
MillerDrive™
MotionMax™
Motion-SPM™
OPTOLOGIC®
OPTOPLANAR®
®
PDP-SPM™
Power-SPM™
PowerTrench®
Programmable Active Droop™
QFET®
QS™
Quiet Series™
RapidConfigure™
Saving our world 1mW at a time™
SmartMax™
SMART START™
SPM®
STEALTH™
SuperFET™
SuperSOT™-3
SuperSOT™-6
SuperSOT™-8
SuperMOS™
®
The Power Franchise®
TinyBoost™
TinyBuck™
TinyLogic®
TINYOPTO™
TinyPower™
TinyPWM™
TinyWire™
µSerDes™
UHC®
Ultra FRFET™
UniFET™
VCX™
VisualMax™
®
tm
tm
Datasheet Identification Product Status Definition
Advance Information Formative or In Design This datasheet contains the design specifications for product development.
Specifications may change in any manner without notice.
Preliminary First Production
This datasheet contains preliminary data; supplementary data will be pub-
lished at a later date. Fairchild Semiconductor reserves the right to make
changes at any time without notice to improve design.
No Identification Needed Full Production This datasheet contains final specifications. Fairchild Semiconductor reserves
the right to make changes at any time without notice to improve the design.
Obsolete Not In Production This datasheet contains specifications on a product that is discontinued by
Fairchild Semiconductor. The datasheet is for reference information only.
FDS6680AS Rev B2(X)
