December 2004
2004 Fairchild Semiconductor Corporation
FDD6680AS Rev A(X)
FDD6680AS
30V N-Channel PowerTrench
SyncFET
TM
General Description
The FDD6680AS is designed to replace a single
MOSFET and Schottky diode in synchronous DC:DC
power supplies. This 30V MOSFET is designed to
maximize power conversion efficiency, providing a low
R
DS(ON)
and low gate charge. The FDD6680AS
includes an integrated Schottky diode using Fairchild's
monolithic SyncFET technology. The performance of
the FDD6680AS as the low-side switch in a
synchronous rectifier is indistinguishable from the
performance of the FDD6680A in parallel with a
Schottky diode.
Applications
DC/DC converter
Low side notebook
Features
55 A, 30 V R
DS(ON)
max= 10.5 m
@ V
GS
= 10 V
R
DS(ON)
max= 13.0 m
@ V
GS
= 4.5 V
Includes SyncFET Schottky body diode
Low gate charge (21nC typical)
High performance trench technology for extremely
low R
DS(ON)
High power and current handling capability
.
G
S
D
TO-252
S
G
D
Absolute Maximum Ratings
T
A
=25
o
C unless otherwise noted
Symbol Parameter
Ratings
Unit
s
V
DSS
Drain-Source
Voltage
30
V
V
GSS
Gate-Source
Voltage
20
V
I
D
Drain Current Continuous
(Note 3)
55
A
Pulsed
(Note 1a)
100
Power Dissipation
(Note 1)
60
(Note 1a)
3.1
P
D
(Note 1b)
1.3
W
T
J
, T
STG
Operating and Storage Junction Temperature Range
55 to +150
C
Thermal Characteristics
R
JC
Thermal Resistance, Junction-to-Case
(Note 1)
2.1
C/W
R
JA
Thermal Resistance, Junction-to-Ambient
(Note 1a)
40
C/W
R
JA
Thermal Resistance, Junction-to-Ambient
(Note 1b)
96
C/W
Package Marking and Ordering Information
Device Marking
Device
Reel Size
Tape width
Quantity
FDD6680AS
FDD6680AS
13''
16mm
2500 units
FDD6680AS FDD6680AS_NL
(Note 4)
13''
16mm
2500 units
FDD6680AS
FDD6680AS Rev A (X)
Electrical Characteristics
T
A
= 25C unless otherwise noted
Symbol Parameter
Test
Conditions
Min
Typ
Max
Units
Drain-Source Avalanche Ratings
(Note 2)
W
DSS
Drain-Source Avalanche Energy
Single Pulse, V
DD
= 15 V,
I
D
=13.5A
54 205 mJ
I
AR
Drain-Source Avalanche Current
13.5
A
Off Characteristics
BV
DSS
DrainSource Breakdown
Voltage
V
GS
= 0 V, I
D
= 1 mA
30
V
BV
DSS
T
J
Breakdown Voltage Temperature
Coefficient
I
D
= 1 mA, Referenced to 25
C
29
mV/
C
I
DSS
Zero Gate Voltage Drain Current V
DS
= 24 V,
V
GS
= 0 V
500
A
I
GSS
GateBody
Leakage
V
GS
=
20 V, V
DS
= 0 V
100
nA
On Characteristics
(Note 2)
V
GS(th)
Gate Threshold Voltage
V
DS
= V
GS
, I
D
= 1 mA
1
1.4
3
V
V
GS(th)
T
J
Gate Threshold Voltage
Temperature Coefficient
I
D
= 1 mA, Referenced to 25
C
3
mV/
C
R
DS(on)
Static DrainSource
OnResistance
V
GS
= 10 V,
I
D
= 12.5 A
V
GS
= 4.5 V,
I
D
= 10 A
V
GS
= 10 V, I
D
= 12.5A, T
J
= 125
C
8.6
10.3
12.5
10.5
13.0
16.0
m
I
D(on)
OnState Drain Current
V
GS
= 10 V,
V
DS
= 5 V
50
A
g
FS
Forward
Transconductance
V
DS
= 15 V,
I
D
= 12.5 A
44
S
Dynamic Characteristics
C
iss
Input
Capacitance
V
DS
= 15 V,
V
GS
= 0 V,
f = 1.0 MHz
1200 pF
C
oss
Output
Capacitance
350 pF
C
rss
Reverse Transfer Capacitance
120 pF
R
G
Gate
Resistance
V
GS
= 15 mV,
f = 1.0 MHz
1.6
Switching Characteristics
(Note 2)
t
d(on)
TurnOn Delay Time
10
20
ns
t
r
TurnOn Rise Time
6
12
ns
t
d(off)
TurnOff Delay Time
28
45
ns
t
f
TurnOff
Fall
Time
V
DD
= 15 V,
I
D
= 1 A,
V
GS
= 10 V,
R
GEN
= 6
12 22 ns
t
d(on)
TurnOn Delay Time
14
25
ns
t
r
TurnOn Rise Time
13
23
ns
t
d(off)
TurnOff Delay Time
20
32
ns
t
f
TurnOff
Fall
Time
V
DD
= 15 V,
I
D
= 1 A,
V
GS
= 4.5 V,
R
GEN
= 6
11 20 ns
Q
g
(TOT)
Total Gate Charge at Vgs=10V
21
29
nC
Q
g
Total Gate Charge at Vgs=5V
11
15
nC
Q
gs
GateSource Charge
3
nC
Q
gd
GateDrain
Charge
V
DD
= 15 V, I
D
= 12.5 A
4
nC
DrainSource Diode Characteristics and Maximum Ratings
I
S
Maximum Continuous DrainSource Diode Forward Current
4.4
A
V
SD
DrainSource Diode Forward
Voltage
V
GS
= 0 V, I
S
= 4.4 A
(Note 2)
V
GS
= 0 V, I
S
= 7 A
(Note 2)
0.5
0.6
0.7 V
t
rr
Diode Reverse Recovery Time
I
F
= 12.5A,
d
iF
/d
t
= 300 A/s
(Note
3)
17 nS
Q
rr
Diode Reverse Recovery Charge
11
nC
FDD6680
A
S
FDD6680AS Rev A (X)
D
R
P
DS(ON)
Electrical Characteristics
T
A
= 25C unless otherwise noted
Notes:
1. R
JA
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. R
JC
is guaranteed by design while R
CA
is determined by the user's board design.
a) R
JA
= 40C/W when mounted on a
1in
2
pad of 2 oz copper
b) R
JA
= 96C/W when mounted
on a minimum pad.
Scale 1 : 1 on letter size paper
2. Pulse Test: Pulse Width < 300
s, Duty Cycle < 2.0%
3. Maximum current is calculated as:
where P
D
is maximum power dissipation at T
C
= 25C and R
DS(on)
is at T
J(max)
and V
GS
= 10V. Package current limitation is 21A
4. FDD6680AS_NL is a lead free product. The FDD6680AS_NL marking will appear on the reel label.
FDD6680
A
S
FDD6680AS Rev A (X)
Typical Characteristics
0
20
40
60
80
100
0
0.5
1
1.5
2
2.5
3
V
DS
, DRAIN-SOURCE VOLTAGE (V)
I
D
,
DRA
I
N
CU
RRE
NT
(A
)
2.5V
4.5V
V
GS
= 10V
3.5V
3.0V
4.0V
6.0V
0.8
1
1.2
1.4
1.6
1.8
2
0
20
40
60
80
100
I
D
, DRAIN CURRENT (A)
R
DS
(O
N)
, N
O
RM
AL
IZE
D
DR
AI
N-
SO
U
RCE
O
N
-
R
ES
I
S
T
ANC
E
V
GS
= 3.0V
6.0V
3.5V
4.0V
10V
4.5V
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
1.6
-50
-25
0
25
50
75
100
125
150
T
J
, JUNCTION TEMPERATURE (
o
C)
R
DS
(O
N)
,
NO
RMAL
I
Z
E
D
DR
AI
N
-
S
O
URC
E
ON
-R
E
S
I
S
T
ANC
E
I
D
= 12.5A
V
GS
=10V
0.008
0.014
0.02
0.026
0.032
2
4
6
8
10
V
GS
, GATE TO SOURCE VOLTAGE (V)
R
DS
(
O
N
)
, O
N
-
R
ESI
S
TA
NCE
(O
H
M
)
I
D
= 6.3A
T
A
= 125
o
C
T
A
=25
o
C
Figure 3. On-Resistance Variation with
Temperature.
Figure 4. On-Resistance Variation with
Gate-to-Source Voltage.
0
20
40
60
80
100
1
1.5
2
2.5
3
3.5
4
4.5
V
GS
, GATE TO SOURCE VOLTAGE (V)
I
D
, D
RAI
N C
URR
ENT
(A
)
T
A
= 125
o
C
25
o
C
-55
o
C
V
DS
= 5V
0.01
0.1
1
10
100
0
0.2
0.4
0.6
0.8
1
V
SD
, BODY DIODE FORWARD VOLTAGE (V)
I
S
,
REV
E
R
S
E D
RAI
N C
URR
ENT
(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.
FDD6680
A
S
FDD6680AS Rev A (X)
Typical Characteristics
(continued)
0
2
4
6
8
10
0
5
10
15
20
25
Q
g
, GATE CHARGE (nC)
V
GS
,
GAT
E
-
S
OU
R
C
E
VO
LTA
GE
(V
)
I
D
= 12.5A
V
DS
= 10V
20V
15V
0
300
600
900
1200
1500
1800
0
5
10
15
20
25
30
V
DS
, DRAIN TO SOURCE VOLTAGE (V)
CA
PA
CI
TA
NCE
(p
F
)
C
iss
f = 1MHz
V
GS
= 0 V
C
rss
C
oss
Figure 7. Gate Charge Characteristics.
Figure 8. Capacitance Characteristics.
0.01
0.1
1
10
100
1000
0.01
0.1
1
10
100
V
DS
, DRAIN-SOURCE VOLTAGE (V)
I
D
, DR
AI
N C
U
R
R
E
N
T (
A
)
DC
1s
100ms
R
DS(ON)
LIMIT
V
GS
= 10V
SINGLE PULSE
R
JA
= 96
o
C/W
T
A
= 25
o
C
10ms
10s
100us
1ms
0
20
40
60
80
100
0.001
0.01
0.1
1
10
100
1000
t
1
, TIME (sec)
P(
p
k
)
,
PEAK T
RAN
SI
ENT
P
O
WER (
W
)
SINGLE PULSE
R
JA
= 96C/W
T
A
= 25C
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
)
,
NO
RM
AL
I
Z
E
D
E
F
F
E
CT
I
V
E
T
R
AN
S
I
E
N
T
T
H
E
R
M
A
L
RE
SI
S
T
AN
CE
R
JA
(t) = r(t) * R
JA
R
JA
= 96 C/W
T
J
- T
A
= P * R
JA
(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 1b.
Transient thermal response will change depending on the circuit board design.
FDD6680
A
S
FDD6680AS Rev A (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
FDD6680AS.
Figure 12. FDD6680AS SyncFET body diode
reverse recovery characteris
For comparison purposes, Figure 13 shows the
reverse recovery characteristics of the body diode
of an equivalent size MOSFET produced without
SyncFET (FDD6680).
Schottky barrie 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
DS
S
,
REVE
RSE
LE
AKAGE
C
URRENT
(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.
Figure 13. Non-SyncFET (FDD6680) body
diode reverse recovery characteristic.
FDD6680
A
S
10nS/div
Curre
nt: 3A/div
10nS/div
Curre
nt: 3A/div
FDD6680AS Rev A (X)
Typical Characteristics
V
DS
L
Figure 12. Unclamped Inductive Load Test
Circuit
Figure 13. Unclamped Inductive
Waveforms
Figure 17. Switching Time Waveforms
R
GE
DUT
V
GS
I
AS
0.01
V
DD
+
-
tp
0V
vary t
P
to obtain
required peak I
AS
V
GS
t
AV
t
P
I
AS
V
DS
V
DD
BV
DSS
Figure 16. Switching Time Test
Circuit
V
DS
R
L
R
GEN
DUT
V
DD
V
GS
Pulse Width
1
s
Duty Cycle
0.1
%
V
GS
+
-
t
r
t
f
t
d(ON)
t
d(OFF
)
t
ON
t
OFF
Pulse Width
10%
10%
90%
10%
90%
50%
90%
50%
0V
0V
V
GS
V
DS
Figure 14. Gate Charge Test Circuit
Figure 15. Gate Charge Waveform
V
GS
Q
GS
Q
GD
Q
G(TOT)
10V
Charge, (nC)
DUT
V
DD
V
GS
I
g(REF
+
-
+
-
Same type as
Drain Current
1
F
10
F
10V
50k
FDD6680
A
S
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.
TRADEMARKS
The following are registered and unregistered trademarks Fairchild Semiconductor owns or is authorized to use and is
not intended to be an exhaustive list of all such trademarks.
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, or (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 significant injury to the
user.
2. A critical component is 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
Datasheet Identification
Product Status
Definition
Advance Information
Preliminary
No Identification Needed
Obsolete
This datasheet contains the design specifications for
product development. Specifications may change in
any manner without notice.
This datasheet contains preliminary data, and
supplementary data will be published at a later date.
Fairchild Semiconductor reserves the right to make
changes at any time without notice in order to improve
design.
This datasheet contains final specifications. Fairchild
Semiconductor reserves the right to make changes at
any time without notice in order to improve design.
This datasheet contains specifications on a product
that has been discontinued by Fairchild semiconductor.
The datasheet is printed for reference information only.
Formative or
In Design
First Production
Full Production
Not In Production
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