October 2005
2005 Fairchild Semiconductor Corporation
BSS138 Rev C(W)
BSS138
N-Channel Logic Level Enhancement Mode Field Effect Transistor
General Description
These N-Channel enhancement mode field effect
transistors are produced using Fairchild's proprietary,
high cell density, DMOS technology. These products
have been designed to minimize on-state resistance
while provide rugged, reliable, and fast switching
performance.These products are particularly suited for
low voltage, low current applications such as small
servo motor control, power MOSFET gate drivers, and
other switching applications.
Features
0.22 A, 50 V. R
DS(ON)
= 3.5
@ V
GS
= 10 V
R
DS(ON)
= 6.0
@ V
GS
= 4.5 V
High density cell design for extremely low R
DS(ON)
Rugged and Reliable
Compact industry standard SOT-23 surface mount
package
G
D
S
SOT-23
D
S
G
Absolute Maximum Ratings
T
A
=25
o
C unless otherwise noted
Symbol Parameter
Ratings
Units
V
DSS
Drain-Source
Voltage
50
V
V
GSS
Gate-Source
Voltage
20
V
I
D
Drain Current Continuous
(Note 1)
0.22 A
Pulsed
0.88
Maximum Power Dissipation
(Note 1)
0.36
W
P
D
Derate Above 25
C
2.8
mW/
C
T
J
, T
STG
Operating and Storage Junction Temperature Range
-
55 to +150
C
T
L
Maximum Lead Temperature for Soldering
Purposes, 1/16" from Case for 10 Seconds
300
C
Thermal Characteristics
R
JA
Thermal Resistance, Junction-to-Ambient
(Note 1)
350
C/W
Package Marking and Ordering Information
Device Marking
Device
Reel Size
Tape width
Quantity
SS
BSS138
7''
8mm
3000 units
B
SS138
BSS138 Rev C(W)
Electrical Characteristics
T
A
= 25C unless otherwise noted
Symbol Parameter
Test
Conditions
Min
Typ Max
Units
Off Characteristics
BV
DSS
DrainSource Breakdown Voltage V
GS
= 0 V,
I
D
= 250
A
50 V
BV
DSS
T
J
Breakdown Voltage Temperature
Coefficient
I
D
= 250
A,Referenced to 25
C
72 mV/
C
I
DSS
Zero Gate Voltage Drain Current
V
DS
= 50 V,
V
GS
= 0 V
0.5
A
V
DS
= 50 V, V
GS
= 0 V T
J
= 125
C
5
A
V
DS
= 30 V,
V
GS
= 0 V
100
nA
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
0.8
1.3
1.5
V
V
GS(th)
T
J
Gate Threshold Voltage
Temperature Coefficient
I
D
= 1 mA,Referenced to 25
C
2
mV/
C
R
DS(on)
Static DrainSource
OnResistance
V
GS
= 10 V,
I
D
= 0.22 A
V
GS
= 4.5 V,
I
D
= 0.22 A
V
GS
= 10 V, I
D
= 0.22 A, T
J
= 125
C
0.7
1.0
1.1
3.5
6.0
5.8
I
D(on)
OnState Drain Current
V
GS
= 10 V,
V
DS
= 5 V
0.2
A
g
FS
Forward
Transconductance V
DS
= 10V,
I
D
= 0.22 A
0.12
0.5
S
Dynamic Characteristics
C
iss
Input
Capacitance
27 pF
C
oss
Output
Capacitance
13 pF
C
rss
Reverse Transfer Capacitance
V
DS
= 25 V,
V
GS
= 0 V,
f = 1.0 MHz
6 pF
R
G
Gate
Resistance
V
GS
= 15 mV, f = 1.0 MHz
9
Switching Characteristics
(Note 2)
t
d(on)
TurnOn Delay Time
2.5
5
ns
t
r
TurnOn
Rise
Time
9
18
ns
t
d(off)
TurnOff
Delay
Time
20
36
ns
t
f
TurnOff Fall Time
V
DD
= 30 V,
I
D
= 0.29 A,
V
GS
= 10 V,
R
GEN
= 6
7
14 ns
Q
g
Total Gate Charge
1.7
2.4
nC
Q
gs
GateSource
Charge
0.1
nC
Q
gd
GateDrain
Charge
V
DS
= 25 V,
I
D
= 0.22 A,
V
GS
= 10 V
0.4 nC
DrainSource Diode Characteristics and Maximum Ratings
I
S
Maximum Continuous DrainSource Diode Forward Current
0.22
A
V
SD
DrainSource Diode Forward
Voltage
V
GS
= 0 V,
I
S
= 0.44 A
(Note 2)
0.8
1.4 V
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) 350C/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%
B
SS138
BSS138 Rev C(W)
Typical Characteristics
0
0.2
0.4
0.6
0.8
1
0
0.5
1
1.5
2
2.5
3
V
DS
, DRAIN TO SOURCE VOLTAGE (V)
I
D
,
DRAI
N CURRE
NT (
A)
V
GS
= 10V
2.0V
3.0V
2.5V
6.0V
4.5V
3.5V
0.6
1
1.4
1.8
2.2
2.6
3
3.4
0
0.2
0.4
0.6
0.8
1
I
D
, DRAIN CURRENT (A)
R
DS
(
O
N)
,
NO
RMALI
Z
E
D
DRAI
N-S
O
URCE
O
N-RE
S
I
S
T
ANCE
V
GS
= 2.5V
4.5V
3.0V
4.0V
3.5V
6.0V
10V
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
1.8
2
-50
-25
0
25
50
75
100
125
150
T
J
, JUNCTION TEMPERATURE (
o
C)
R
DS
(
O
N)
, NO
RMALIZE
D
DRAIN-
S
O
URCE
O
N-
RE
S
IS
TANC
E
I
D
= 220mA
V
GS
= 10V
0.5
1.1
1.7
2.3
2.9
3.5
4.1
0
2
4
6
8
10
V
GS
, GATE TO SOURCE VOLTAGE (V)
R
DS
(
O
N)
,
O
N
-RE
S
I
S
T
ANCE
(O
HM)
I
D
= 110mA
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
0.1
0.2
0.3
0.4
0.5
0.6
0.5
1
1.5
2
2.5
3
3.5
V
GS
, GATE TO SOURCE VOLTAGE (V)
I
D
,
DRAI
N CURRE
NT (A)
T
A
= -55
o
C
25
o
C
125
o
C
V
DS
= 10V
0.0001
0.001
0.01
0.1
1
0
0.2
0.4
0.6
0.8
1
1.2
V
SD
,
BODY DIODE FORWARD VOLTAGE (V)
I
S
,
R
EVER
SE
DRAI
N CURRE
NT (A)
V
GS
= 0V
T
A
= 125
o
C
25
o
C
-55
o
C
Figure 5. Transfer Characteristics.
Figure 6. Body Diode Forward Voltage Variation
with Source Current and Temperature.
B
SS138
BSS138 Rev C(W)
Typical Characteristics
0
2
4
6
8
10
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
Q
g
, GATE CHARGE (nC)
V
GS
, G
A
TE
-
S
O
URCE
V
O
LTAG
E
(
V
)
I
D
= 220mA
V
DS
= 8V
25V
30V
0
20
40
60
80
100
0
10
20
30
40
50
V
DS
, DRAIN TO SOURCE VOLTAGE (V)
CAP
ACI
TANCE
(pF)
C
ISS
C
OSS
C
RSS
f = 1 MHz
V
GS
= 0 V
Figure 7. Gate Charge Characteristics.
Figure 8. Capacitance Characteristics.
0.001
0.01
0.1
1
10
0.1
1
10
100
V
DS
, DRAIN-SOURCE VOLTAGE (V)
I
D
,
DRAI
N CURRE
NT (
A)
DC
1s
100ms
100
s
R
DS(ON)
LIMIT
V
GS
= 10V
SINGLE PULSE
R
JA
= 350
o
C/W
T
A
= 25
o
C
10ms
1ms
0
1
2
3
4
5
0.001
0.01
0.1
1
10
100
1000
t
1
, TIME (sec)
P(
p
k
)
,
PEA
K
T
R
A
N
SI
EN
T
POW
ER
(
W
)
SINGLE PULSE
R
JA
= 350C/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
ALI
Z
E
D
E
FFE
CTI
V
E
TRANS
I
E
N
T
T
H
ER
M
A
L
R
ESIST
A
N
C
E
R
JA
(t) = r(t) * R
JA
R
JA
= 350
o
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 1a.
Transient thermal response will change depending on the circuit board design.
B
SS138
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.
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In Design
First Production
Full Production
Not In Production
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