SmartSwitch
TM
AAT4670
Dual-Input, Dual-Output Load Switch
4670.2005.10.1.2
1
General Description
The AAT4670 SmartSwitch is a member of
AnalogicTech's Application Specific Power MOS-
FETTM (ASPMTM) product family. The AAT4670
consists of dual, independent, 1A current limited,
slew rate controlled P-channel MOSFET power
switches with a dedicated source and drain pin
assigned to each switch. The internal circuitry auto-
matically derives power from the higher of the two
input power source pins with a low operating quies-
cent current of 18A. In shutdown mode, the supply
current decreases to less than 1A. The switches
operate with inputs ranging from 2.2V to 5.5V, mak-
ing them ideal for 2.5V, 3V, and 5V systems. The
dual configuration permits integration of the load
switch function for systems with two different power
busses. Independent under-voltage lockout circuits
will shut down the corresponding switch if its input
voltage falls below the under-voltage lockout thresh-
old. If the die temperature reaches the thermal limit,
both switches thermal cycle off and on indefinitely
without damage until the thermal condition is
removed. An open drain FAULT output signals an
over-current or over-temperature condition for each
channel. Input logic levels are TTL compatible.
The AAT4670 is available in a Pb-free, space-sav-
ing, thermally-enhanced TDFN 3x3x0.8mm 12-
lead package. The device is also available in a Pb-
free 8-pin SOP, TSSOP, or MSOP package and is
specified over the -40C to +85C temperature
range.
Features
2.2V to 5.5V Input Voltage Range
1A Current Limit Per Channel
95m
Typical R
DS(ON)
Fast Transient Response:
-- <1s Response to Short Circuit
Low 18A Quiescent Current
1A Max with Switches Off
Slew Rate Controlled
Thermal Shutdown
Fault Flags with 3ms Blanking
Under-Voltage Lockout
Temperature Range: -40C to +85C
Available in TDFN33-12, SOP-8, TSSOP-8, or
MSOP-8 Package
Applications
Hot Swap Supplies
Media Bay
Notebook Computer
PDA, Subnotebook
Peripheral Ports
USB Ports
Typical Application
INA
C
INA
1
F
C
INB
1
F
INB
EN
FAULTA
OUTA
GND
AAT4670
7
6
1
4
8
INA
INB
GND
GND
OUTA
EN
FAULTA
FAULTB
FAULTB
OUTB
5
OUTB
2
3
C
OUTA
1
F
C
OUTB
1
F
AAT4670
Dual-Input, Dual-Output Load Switch
2
4670.2005.10.1.2
Pin Descriptions
Pin Configuration
SOP-8
TSSOP-8
MSOP-8
TDFN33-12
1
2
INB
OUTB
INA
OUTA
EN
FAULTA
FAULTB
GND
1
2
3
4
8
7
6
5
EN
FAULTA
FAULTB
GND
OUTB
INB
INA
OUTA
4
3
2
1
5
6
7
8
1
2
INB
OUTB
INA
OUTA
EN
FAULTA
FAULTB
GND
1
2
3
4
8
7
6
5
Pin #
TDFN Other Pkgs Symbol
Function
2
1
EN
Active-low enable input (logic low turns the switches on).
3
2
FAULTA
Open drain output; signals over-current for OUTA and over-tempera-
ture condition.
4
3
FAULTB
Open drain output; signals over-current for OUTB and over-tempera-
ture condition.
5
4
GND
Ground connection.
1, 12
5
OUTA
P-channel MOSFET drain channel A.
10, 11
6
INA
P-channel MOSFET source channel A.
8, 9
7
INB
P-channel MOSFET source channel B.
6, 7
8
OUTB
P-channel MOSFET drain channel B.
OUTA
EN
FAULTA
1
FAULTB
GND
OUTB
OUTA
INA
INA
INB
INB
OUTB
2
3
4
5
6
12
11
10
9
8
7
AAT4670
Dual-Input, Dual-Output Load Switch
4670.2005.10.1.2
3
Absolute Maximum Ratings
1
T
A
= 25C, unless otherwise noted.
Thermal Characteristics
3
Symbol
Description
Value
Units
JA
Maximum Thermal Resistance (SOP-8)
100
C/W
JA
Maximum Thermal Resistance (TDFN33-12)
50
C/W
P
D
Maximum Power Dissipation (SOP-8)
1.25
W
P
D
Maximum Power Dissipation (TDFN33-12)
2.0
W
Symbol
Description
Value
Units
V
INA,B
INA or INB to GND
-0.3 to 6
V
V
OUTA,B
OUTA or OUTB to GND
-0.3 to 6
V
V
FAULTA,B
FAULTA or FAULTB to GND
-0.3 to 6
V
I
OUT
Output Current
Internally Limited
A
T
J
Operating Junction Temperature Range
-40 to 150
C
V
ESD
ESD Rating
2
- HBM
4000
V
T
LEAD
Maximum Soldering Temperature (at Leads)
300
C
1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at condi-
tions other than the operating conditions specified is not implied. Only one Absolute Maximum Rating should be applied at any one time.
2. Human body model is a 100pF capacitor discharged through a 1.5k
resistor into each pin.
3. Mounted on a demo board.
Electrical Characteristics
V
IN
= 5V, T
A
= 25C, unless otherwise noted. Bold values designate -40C to +85C temperature range.
Symbol Description
Conditions
Min Typ Max Units
V
IN
Operation Voltage
2.2
5.5
V
I
Q
Quiescent Current
V
INA
or V
INB
= 5V I
OUTA
= I
OUTB
= 0
18
40
A
I
Q(OFF)
Off Supply Current
EN = V
IN
, V
INA
= V
INB
= 5V, OUTA, OUTB Open
1
A
I
SD(OFF)
Off Switch Current
EN = V
IN
, V
INA
= V
INB
= 5V, V
OUTA
= V
OUTB
= 0V
0.1
1
A
V
UVLO
Under-Voltage Lockout
1.7
2.2
V
R
DS(ON)
On-Resistance Channel
V
IN
= 5.0V
95
130
m
A or B
V
IN
= 3.0V
105
150
T
CRDS
Switch Resistance
2800
ppm/C
Temperature Coefficient
I
LIM
Current Limit Channel A or B V
OUT
< V
IN
- 0.5V
1.0
1.25
1.50
A
t
1
Output Turn-On Delay Time
V
IN
= 5V, OUT = 0 to 10%, R
LOAD
= 20
100
1000
s
t
2
Output Rise Time
V
IN
= 5V, OUT = 10% to 90%, R
LOAD
= 20
100
1000
s
t
3
Output Turn-Off Delay Time
V
IN
= 5V, OUT = 100% to 90%, R
LOAD
= 20
10
20
s
t
4
Output Fall Time
V
IN
= 5V, OUT = 90% to 10%, R
LOAD
= 20
5
20
s
V
EN(L)
EN Input Low Voltage
V
IN
= 2.7V to 5.5V
1
0.8
V
V
EN(H)
EN Input High Voltage
V
IN
= 2.7V to < 3.6V
2.0
V
V
IN
= 3.6V to 5.5V
2.4
I
EN(SINK)
EN Input Leakage
V
EN
= 5.5V
0.01
1
A
t
RESP
Current Loop Response
V
IN
= 5V
750
ns
V
FAULTLOW
FAULT Logic Output Low
I
SINK
= 1mA
0.4
V
I
SINK
FAULT Logic Output High
V
FAULT
= 5.5V
0.5
1
A
Leakage Current
T
blank
Fault Blanking Time
3
ms
T
SD
Over-Temperature Threshold
125
C
AAT4670
Dual-Input, Dual-Output Load Switch
4
4670.2005.10.1.2
1. For V
IN
outside this range, consult typical EN threshold curve.
Typical Characteristics
R
DS(ON)
vs. Temperature
60
70
80
90
100
110
120
130
140
150
-40
-20
0
20
40
60
80
100
120
Temperature (
C)
R
DS(ON)
(m
)
V
IN
= 3V
V
IN
= 5V
Current Limit vs. Output Voltage
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
0
1
2
3
4
5
Output Voltage (V)
Output Current (A)
Off-Switch Current vs. Temperature
0.0000
0.0001
0.0010
0.0100
0.1000
1.0000
-40
-20
0
20
40
60
80
100
120
Temperature (
C)
Off-Switch Current (
A)
Off-Supply Current vs. Temperature
0.0000
0.0001
0.0010
0.0100
0.1000
1.0000
-40
-20
0
20
40
60
80
100
120
Temperature (
C)
Off-Supply Current (
A)
Quiescent Current vs. Input Voltage
0
2
4
6
8
10
12
14
16
18
20
0
1
2
3
4
5
6
Input Voltage (V)
Input Current (
A)
Quiescent Current vs. Temperature
0
5
10
15
20
25
30
-40
-20
0
20
40
60
80
100
120
Temperature (
C)
Quiescent Current (
A)
AAT4670
Dual-Input, Dual-Output Load Switch
4670.2005.10.1.2
5
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