SmartSwitch™
General Description
The AAT4610 SmartSwitch™ is a member of
AnalogicTech's Application Specific Power
MOSFET™ (ASPM™) product family. It is a Current
Limited P-channel MOSFET power switch designed
for high-side load-switching applications. This switch
operates with inputs ranging from 2.7V to 5.5V, mak-
ing it ideal for both 3V and 5V systems. An inte-
grated current-limiting circuit protects the input sup-
ply against large currents which may cause the sup-
ply to fall out of regulation. The AAT4610 is also pro-
tected from thermal overload which limits power dis-
sipation and junction temperatures. It can be used
to control loads that require up to 1 A. Current limit
threshold is programmed with a resistor from SET to
ground. The quiescent supply current is typically a
low 15µA max. In shutdown mode, the supply cur-
rent decreases to less than 1µA.
The AAT4610 is available in a 5 pin SOT-23 spec-
ified over -40 to 85°C.
The AAT4600 Series is a family of adjustable and
fixed SmartSwitch™ with a range of current han-
dling capabilities. Available are single versions in
adj. current limit (AAT4600, AAT4601) as well as in
fixed current limit (AAT4602, AAT4625). Dual ver-
sions (AAT4620, AAT4626) are also available.
Features
• 2.7V to 5.5V Input voltage range
• Programmable over current threshold
• Fast transient response:
• <1µs response to short circuit
• Low quiescent current
• 15µA typical
• 1µA max with Switch off
• 160mΩ typical R DS(ON)
• Only 2.5V needed for ON/OFF Control
• Undervoltage Lockout
• Thermal shutdown
• Temp range -40 to 85°C
• 4kV ESD Rating
• UL Approved—File No. E217765
• 5 pin SOT-23 package
Applications
• Peripheral ports
• Notebook computers
• Personal communication devices
• Hot swap supplies
UL Recognized Component
AAT4610
Current Limited Load Switch in SOT-23 Package
Typical Application
AAT4610
5
4
2
3
1
ON/(ON)
IN
SET
INPUT
GND GND
GND
OUT
SOT-23
OUTPUT
ON (ON)
0.47µF
RSET
1µF
Preliminary Information
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AAT4610
Current Limited Load Switch in SOT-23 Package
24610.2001.9.0.97
Pin Configuration
5-Pin SOT-23
(Top View)
Pin Descriptions
Pin # Symbol Function
1 OUT P-channel MOSFET drain. Connect 0.47µF capacitor from OUT to GND.
2 GND Ground connection
3 SET Current-Limit Set Input. A resistor from SET to ground sets the current limit for
the switch.
4 ON Enable Input. Two versions are available, active-high and active-low. See order-
ing information for details.
5 IN P-channel MOSFET source. Connect 1µF capacitor from IN to GND.
1
2
3
SET
OUT
4
5
GND
IN
ON
AAT4610
Current Limited Load Switch in SOT-23 Package
4610.2001.9.0.97 3
Absolute Maximum Ratings (TA=25°C unless otherwise noted)
Note: Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at con-
ditions other than the operating conditions specified is not implied. Only one Absolute Maximum rating should be applied at any one time.
Note 1: Human body model is a 100pF capacitor discharged through a 1.5kΩ resistor into each pin.
Thermal Characteristics
Note 2: Mounted on a demo board.
Electrical Characteristics (VIN = 5V, TA= -40 to 85°C unless otherwise noted. Typical values
are at TA=25°C)
Symbol Description Conditions Min Typ Max Units
VIN Operation Voltage 2.7 5.5 V
IQQuiescent Current VIN = 5V, ON (ON) = active, IOUT = 0 15 30 µA
IQ(OFF) Off Supply Current ON (ON) =inactive, VIN = 5.5V 1 µA
ISD(OFF) Off Switch Current ON (ON) = inactive, VIN = 5.5V, VOUT = 0 .03 15 µA
VUVLO Undervoltage Lockout Rising edge, 1% hysteresis, 2.0 2.3 2.7 V
VIN=5.0V 160 180 mΩ
RDS(ON) On-Resistance VIN=4.5V 165 mΩ
VIN=3.0V 195 230 mΩ
ILIM Current Limit RSET = 6.8kΩ .75 1 1.25 A
ILIM(MIN) Minimum Current Limit 150 mA
VON(L) ON (ON) Input Low Voltage 0.8 V
VON(H) ON (ON) Input High Voltage VIN=2.7V to 3.6V 2.0 V
VIN=4.5V to 5.5V 2.4 V
ION(SINK) ON (ON) Input leakage VON = 5.5V 0.01 1 µA
TRESP Current Limit Response Time VIN=5V 0.8 µs
TOFF Turn-Off Time VIN=5V, RL=10Ω 0.4 2 µs
TON Turn-On Time VIN=5V, RL=10Ω 40 200 µs
Symbol Description Value Units
ΘJA Thermal Resistance2150 °C/W
PDPower Dissipation2667 mW
Symbol Description Value Units
VIN IN to GND -0.3 to 6 V
VON ON(ON) to GND -0.3 to VIN+0.3 V
VSET, VOUT SET, OUT to GND -0.3 to VIN+0.3 V
IMAX Maximum Continuous Switch Current 2 A
TJOperating Junction Temperature Range -40 to 150 °C
TLEAD Maximum Soldering Temperature (at Leads) 300 °C
VESD ESD Rating1- HBM 4000 V
Typical Characteristics
(Unless otherwise noted, VIN = 5V, TA= 25°C)
Off-Switch Current vs. Temperature
Temperature (C )
Off-Switch Current (µA)
0.001
0.01
0.1
1
10
-40 -20 0 20 40 60 80 100 120
Off-Supply Current vs. Temperature
0.01
0.1
1
10
-40 -20 0 20 40 60 80 100 120
Temperature (C )
Off-Supply Current (µA)
RDS(ON) vs. Temperature
0
50
100
150
200
250
-40 -20 0 20 40 60 80 100
Te
RDS(ON) (mΩ)
mperature (C)
Input = 3V
Input = 5V
Output Current vs VOUT
0
0.2
0.4
0.6
012345
Vout ( V )
Output Current (A)
R
SET =16 kΩ
Quiescent Current
0
10
20
30
40
2.5 3 3.5 4 4.5 5 5.5
Input ( V )
Input ( µA )
Quiescent Current vs. Temperature
0
5
10
15
20
25
-40 -20 0 20 40 60 80 100 120
Temperature
Quiescent Current (µA)
(C)
AAT4610
Current Limited Load Switch in SOT-23 Package
44610.2001.9.0.97
(Unless otherwise noted, VIN = 5V, TA= 25°C)
Short Circuit through 0.6Ω
0
2
4
6
8
0123
Time (µs)
Input and Output
-3
0
3
6
9
Output (A)
Output Current
Input Voltage
Output Voltage
(V)
Short Circuit through 0.3Ω
0
2
4
6
8
0123
Time (µs)
Input and Output
-4
0
4
8
12
Output (A)
Output Current
Input Voltage
Output Voltage
(V)
-1
0
1
2
3
4
5
6
- 0.5 0 0.5 1
Time (µs)
Voltage ( V )
OutputON
IOUT =I LIMIT
Turn-Off
RL = 10Ω
Turn-On
RL = 10Ω, CL = 0.47µF
-1
0
1
2
3
4
5
6
- 20 0 20 40 60
Time (µs)
Voltage ( V )
OutputON
IOUT =I LIMIT
Turn-OFF vs. Temperature
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
- 40 - 20 0 20 40 60 80 100
Temperature (C )
Turn-OFF Time (µs)
Vin = 3V
Vin = 5V
Turn-ON vs. Temperature
0
10
20
30
40
50
60
70
80
-40 -20 0 20 40 60 80 100
Temperatur e ( C )
Turn-ON Time (µs)
Vin=5V
Vin=3V
AAT4610
Current Limited Load Switch in SOT-23 Package
4610.2001.9.0.97 5
(Unless otherwise noted, VIN = 5V, TA= 25°C)
Current Limit v. Temperature
-6%
-4%
-2%
0%
2%
4%
6%
-50 - 25 0 25 50 75 100
Temperature (C)
Current Limit (%)
RSET= 22.1k
VIN -VOUT=0.5V
RSET coefficent vs ILIM
5
6
7
8
9
10
0 0.5 1 1.5 2
ILIM (A)
RSET ILIM Product ( kV )
RSET vs ILIM
1
10
100
0.1 101
ILIM (A)
RSET (kΩ)
AAT4610
Current Limited Load Switch in SOT-23 Package
64610.2001.9.0.97
Functional Block Diagram
Current
Limit
1.2V
Reference
Under-
voltage
Lockout
Over-Temp
Protection
OUT
SET
GND
RSET
ON (ON)
IN
AAT4610
Current Limited Load Switch in SOT-23 Package
4610.2001.9.0.97 7
Applications Information
Setting Current Limit
In most applications, the variation in ILIM must be
taken into account when determining RSET. The ILIM
variation is due to processing variations from part
to part, as well as variations in the voltages at IN
(pin 5) and OUT (pin 3), plus the operating temper-
ature. See charts "Current Limit vs. Temperature",
and "Output Current vs. VOUT". Together these
three factors add up to a ±25% tolerance (see ILIM
specification in Electrical Characteristics section).
In the figure below, a cold device with a statistical-
ly higher current limit, and a hot device with a sta-
tistically lower current limit, both with RSET equal to
10.5kΩ are shown. While the chart, "R
SET vs. ILIM"
indicates an ILIM of 0.7A with an RSET of 10.5kΩ ,
this figure shows that the actual current limit will be
at least 0.525A, and no greater than 0.880A.
To determine RSET, start with the maximum current
drawn by the load, and multiply it by 1.33. (typi-
cal_ILIM = minimum_ILIM / 0.75) This is the typical
current limit value. Next, refer to "RSET vs. ILIM" and
find the RSET that corresponds to the typical current
limit value. Choose the largest resistor available
that is less than or equal to it. For greater precision,
the value of RSET may also be calculated using the
ILIM RSET product found in the chart "RSET coeffi-
cient vs. ILIM". The maximum current is derived by
multiplying the typical current for the chosen RSET
in the chart by 1.25. A few standard resistor values
are listed in the table "Current Limit RSET Values".
Current Limit RSET Values
Example: A USB port requires 0.5A. 0.5A multiplied
by 1.33 is 0.665A. From the chart named "RSET vs.
ILIM", RSET should be less than 11kΩ. 10.5 kΩ is a
standard value that is a little less than 11kΩ but
very close. The chart reads approximately 0.700A
as a typical ILIM value for 10.5kΩ . Multiplying
0.700A by 0.75 and 1.25 shows that the AAT4610
will limit the load current to greater than 0.525A but
less than 0.875A.
Current Limit Using10.5 kΩ
0
0.2
0.4
0.6
0.8
1
1.2
012345
Vout (V )
ILIM (A)
0.88 A
0.525 A
Device with high current limit at -40 C
Device with low current limit at 85 C
AAT4610
Current Limited Load Switch in SOT-23 Package
84610.2001.9.0.97
RSET Current Device will Device always
(kΩ ) Limit typ not current current limits
(mA) limit below: below:
(mA) (mA)
40.2 200 150 250
30.9 250 188 313
24.9 300 225 375
22.1 350 263 438
19.6 400 300 500
17.8 450 338 563
16.2 500 375 625
14.7 550 413 688
13.0 600 450 750
10.5 700 525 875
8.87 800 600 1000
7.50 900 675 1125
6.81 1000 750 1250
6.04 1100 825 1375
5.49 1200 900 1500
4.99 1300 975 1625
4.64 1400 1050 1750
Operation in Current Limit
When a heavy load is applied to the output of the
AAT4610, the load current is limited to the value of
ILIM determined by RSET. See the figure "Overload
Operation". Since the load is demanding more cur-
rent than ILIM, the voltage at the output drops. This
causes the AAT4610 to dissipate a larger than nor-
mal quantity of power, and its die temperature to
increase. When the die temperature exceeds an
over temperature limit, the AAT4610 will shut down
until is has cooled sufficiently, at which point it will
startup again. The AAT4610 will continue to cycle
on and off until the load is removed, power is
removed, or until a logic high level is applied to ON
(pin 4).
Enable Input
In many systems, power planes are controlled by
integrated circuits which run at lower voltages than
the power plane itself. The enable input ON (pin 4)
of the AAT4610 has low and high threshold volt-
ages that accommodate this condition. The thresh-
old voltages are compatible with 5 volt TTL, and 2.5
volt to 5 volt CMOS.
Reverse Voltage
The AAT4610 is designed to control current flowing
from IN to OUT. If a voltage is applied to OUT which
is greater than the voltage on IN, large currents may
flow. This could cause damage to the AAT4610.
AAT4610
Current Limited Load Switch in SOT-23 Package
4610.2001.9.0.97 9
Overload Operation
0
1
2
3
4
5
-0.050 0.050.10.150.20.250.3
Tim e ( s )
Output ( V )
0
0.25
0.5
0.75
1
Output (A)
Output Current
Output Voltage
1Ωload is turned on at time = 0
Ordering Information
Package Information
SOT-23-5
E
A
A1
c
b
D
e
S1
L
I
H
S
Package Enable Marking Part Number
Bulk Tape and Reel
SOT-23-5 ON (active low) N/A AAT4610IGV-T1
SOT-23-5 ON (active high) N/A AAT4610IGV-1-T1
AAT4610
Current Limited Load Switch in SOT-23 Package
Dim Millimeters Inches
Min Max Min Max
A 0.95 1.45 0.037 0.057
A1 0.05 0.15 0.002 0.006
A2 0.90 1.30 0.035 0.051
b 0.35 0.50 0.014 0.019
c 0.08 0.20 0.003 0.078
D 2.84 3.00 0.112 0.112
E 1.50 1.70 0.059 0.067
e 1.90 0.0748
H 2.60 3.00 0.102 0.118
L 0.35 0.55 .0137 .0216
S 0.47 0.55 0.019 .0216
S1 .95 0.037
Θ 0° 10° 0° 10°
104610.2001.9.0.97
Advanced Analogic Technologies, Inc.
1250 Oakmead Parkway, Suite 310, Sunnyvale, CA 94086
Phone (408) 524-9684
Fax (408) 524-9689
