AAT4610B
Current Limited Load SwitchSmartSwitchTM
PRODUCT DATASHEET
4610B.2009.09.1.1 1
www.analogictech.com
General Description
The AAT4610B SmartSwitch is a current limited P-channel
MOSFET power switch designed for high-side load
switching applications. This switch operates with inputs
ranging from 2.4V to 5.5V, making it ideal for both 3V
and 5V systems. An integrated current-limiting circuit
protects the input supply against large currents which
may cause the supply to fall out of regulation. The
AAT4610B is also protected from thermal overload which
limits power dissipation and junction temperatures. It
can be used to control loads that require up to 1A.
Current limit threshold is programmed with a resistor
from SET to ground. The quiescent supply current is
typically a low 9μA. In shutdown mode, the supply cur-
rent decreases to less than 1μA.
The AAT4610B is available in a Pb-free 5-pin SOT23 or
8-pin SC70JW package and is specified over the -40°C to
+85°C temperature range.
Features
• Input Voltage Range: 2.4V to 5.5V
• Programmable Over-Current Threshold
• Fast Transient Response:
▪ 400ns Response to Short Circuit
• Low Quiescent Current
▪ 9μA Typical
▪ 1μA Max with Switch Off
• 145mΩ Typical RDS(ON)
• Only 2.5V Needed for ON/OFF Control
• Under-Voltage Lockout
• Thermal Shutdown
• 4kV ESD Rating
• UL Approved—File No. E217765
• 5-Pin SOT23 or 8-Pin SC70JW Package
• Temperature Range: -40°C to +85°C
Applications
• Hot Swap Supplies
• Notebook Computers
• Peripheral Ports
• Personal Communication Devices
UL Recognized Component
Typical Application
AAT4610B
ON/(ON)
IN
SET
INPUT
GND GND
GND
OUT
SOT23-5
OUTPUT
ON (ON)
0.47μF
RSET
1μF
AAT4610B
Current Limited Load SwitchSmartSwitchTM
PRODUCT DATASHEET
2 4610B.2009.09.1.1
www.analogictech.com
Pin Descriptions
Pin Number
Symbol Function
SOT23-5 SC70JW-8
1 5 OUT P-channel MOSFET drain. Connect a 0.47μF capacitor from OUT to GND.
2 6, 7, 8 GND Ground connection.
3 1 SET Current limit set input. A resistor from SET to ground sets the current limit for
the switch.
42ON Enable input. Two versions are available, active-high and active-low. See Order-
ing Information for details.
5 3, 4 IN P-channel MOSFET source. Connect a 1μF capacitor from IN to GND.
Pin Configuration
SOT23-5 SC70JW-8
(Top View) (Top View)
GND
IN
ON
SET
OUT
1
2
34
5
ON
IN
IN
GND
GND
GND
OUT
SET 1
2
3
45
6
7
8
AAT4610B
Current Limited Load SwitchSmartSwitchTM
PRODUCT DATASHEET
4610B.2009.09.1.1 3
www.analogictech.com
Absolute Maximum Ratings1
TA = 25°C, unless otherwise noted.
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 Rating2 - HBM 4000 V
Thermal Characteristics3
Symbol Description Value Units
ΘJA Thermal Resistance (SOT23-5 or SC70JW-8) 150 °C/W
PDPower Dissipation (SOT23-5 or SC70JW-8) 667 mW
1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at conditions 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 1.5kΩ resistor into each pin.
3. Mounted on a demo board.
AAT4610B
Current Limited Load SwitchSmartSwitchTM
PRODUCT DATASHEET
4 4610B.2009.09.1.1
www.analogictech.com
Electrical Characteristics
VIN = 5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are TA = 25°C.
Symbol Description Conditions Min Typ Max Units
VIN Operation Voltage 2.4 5.5 V
IQQuiescent Current VIN = 5V, ON (ON) = Active, IOUT = 0 9 25 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 0.01 1 μA
VUVLO Under-Voltage Lockout Rising Edge, 1% Hysteresis 1.8 2.4 V
RDS(ON) On Resistance
VIN = 5.0V, TA = 25°C 145 180
mΩVIN = 4.5V, TA = 25°C 150
VIN = 3.0V, TA = 25°C 190 230
TCRDS On Resistance Temperature Coeffi cient 2800 ppm/°C
ILIM Current Limit RSET = 6.8kΩ1.2 1.6 2.0 A
ILIM(MIN) Minimum Current Limit 130 mA
VON(L) ON (ON) Input Low Voltage VIN = 2.7V to 5.5V10.8 V
VON(H) ON (ON) Input High Voltage VIN = 2.7V to < 4.2V12.0 V
VIN ≥ 4.2V to 5.0V12.4
ION(SINK) ON (ON) Input Leakage VON = 5.5V 0.01 1 μA
TRESP Current Limit Response Time VIN = 5V 0.4 μs
TOFF Turn-Off Time VIN = 5V, RL = 10Ω412 μs
TON Turn-On Time VIN = 5V, RL = 10Ω12 200 μs
TSD Over-Temperature Threshold VIN = 5V TJ Increasing 125 °C
TJ Decreasing 115
1. For VIN outside this range, consult Typical ON (ON) Threshold curve.
AAT4610B
Current Limited Load SwitchSmartSwitchTM
PRODUCT DATASHEET
4610B.2009.09.1.1 5
www.analogictech.com
Typical Characteristics
Unless otherwise noted, VIN = 5V, TA = 25°C.
Quiescent Current vs. Temperature
0
5
10
15
20
-40 -20 0 20 40 60 80 100 120
Temperature (
°
C)
Quiescent Current (μA)
Quiescent Current vs. Input Voltage
0
5
10
15
20
0123456
Input Voltage (V)
Quiescent Current (μA)
Output Current vs. Output Voltage
(RSET = 22.1kΩ)
010.5 1.5 2.5 3.5 4.52345
Output Voltage (V)
Output Current (A)
0
0.1
0.2
0.3
0.4
0.5
RDS(ON) vs. Temperature
0
20
40
60
80
100
120
140
160
180
200
220
240
-40 -20 0 20 40 60 80 100 120
Temperature (˚
˚
C)
RDS(ON) (mΩ)
Input = 3V
Input = 5V
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)
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
AAT4610B
Current Limited Load SwitchSmartSwitchTM
PRODUCT DATASHEET
6 4610B.2009.09.1.1
www.analogictech.com
Typical Characteristics
Unless otherwise noted, VIN = 5V, TA = 25°C.
Turn-On vs. Temperature
(RLOAD = 10Ω; CLOAD = 0.47μF)
0
10
20
30
-40-200 20406080100
Temperature (
°
C)
Turn-On Time (μs)
VIN = 3V
VIN = 5V
Turn-Off vs. Temperature
(RLOAD = 10Ω; CLOAD = 0.47μF)
0
1
2
3
4
5
6
-40 -20 0 20 40 60 80 100
Temperature (
°
C)
Turn-Off Time (μs)
VIN = 3V
VIN = 5V
Turn-On
(RL = 10Ω; CL = 0.47μF)
-1
0
1
2
3
4
5
6
-10 -5 0 5 10 1520 2530 3540 45 50
Time (μs)
Voltage (V)
OutputON
Turn-Off
(RL = 10Ω
Ω
; CL = 0.47μF)
-1
0
1
2
3
4
5
6
-10-50 5 101520253035404550
Time (μs)
Voltage (V)
OutputON
Short-Circuit Through 0.3Ω
0
1
2
3
4
5
6
7
8
-0.5 0.0 0.5 1.0 1.5 2.0 2.5 3.0
Time (μs)
Input and Output Voltage (V)
-4
-2
0
2
4
6
8
10
12
Output Current (A)
Input Voltage
Output Current
Output Voltage
VIH
VIH
VIL
and VIL vs. VIN
0.80
1.00
1.20
1.40
1.60
1.80
2.00
2.20
2.5 3.0 3.5 4.0 4.5 5.0 5.5
VIN (V)
AAT4610B
Current Limited Load SwitchSmartSwitchTM
PRODUCT DATASHEET
4610B.2009.09.1.1 7
www.analogictech.com
Typical Characteristics
Unless otherwise noted, VIN = 5V, TA = 25°C.
RSET vs. ILIM
1
10
100
100 100001000
ILIM (mA)
RSET (kΩ)
RSET Coefficient vs. ILIM
5
6
7
8
9
10
0 0.5 1 1.5 2
ILIM (A)
RSET ILIM Product (kV)
Output Current vs. Temperature
(RSET = 22.1kΩ)
-0.1
0
0.1
0.2
0.3
0.4
0.5
-50 - 25 0 25 50 75 100
Temperature (°
°
C)
Current Limit (%)
AAT4610B
Current Limited Load SwitchSmartSwitchTM
PRODUCT DATASHEET
8 4610B.2009.09.1.1
www.analogictech.com
AAT4610B
Current Limited Load SwitchSmartSwitchTM
PRODUCT DATASHEET
8 4610B.2009.09.1.1
www.analogictech.com
Functional Block Diagram
Current
Limit
1.2V
Reference
Under-
Voltage
Lockout
Over-Temperature
Protection
OUT
SET
GND
RSET
ON (ON)
IN
Application 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 and OUT, plus the operat-
ing temperature. 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). Figure
1 illustrates a cold device with a statistically higher cur-
rent limit and a hot device with a statistically lower cur-
rent limit, both with RSET equal to 8.87kΩ. While the
chart, "RSET vs. ILIM” indicates an ILIM of 1.1A with an RSET
of 10.5kΩ, this figure shows that the actual current limit
will be at least 0.825A and no greater than 1.375A.
To determine RSET, start with the maximum current drawn
by the load and multiply it by 1.33 (typical ILIM = mini-
mum ILIM / 0.75). This is the typical current limit value.
Next, refer to “RSET vs. ILIM” and find the RSET that corre-
sponds 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 cal-
culated using the ILIM RSET product found in the chart “RSET
Coefficient 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 Table 1.
Current Limit vs. Output Voltage
(RSET = 8.87kΩ)
0.2
0.4
0
0.6
0.8
1.2
1.0
1.4
1.6
012345
Output Voltage (V)
Current Limit (A)
IMIN = 0.825A
IMAX = 1.375A
Device with high current limit at -40°C
Device with low current limit at 85°C
Figure 1: Current Limit Using 10.5kΩ.
AAT4610B
Current Limited Load SwitchSmartSwitchTM
PRODUCT DATASHEET
4610B.2009.09.1.1 9
www.analogictech.com
AAT4610B
Current Limited Load SwitchSmartSwitchTM
PRODUCT DATASHEET
4610B.2009.09.1.1 9
www.analogictech.com
Overload Operation
0
1
2
3
4
5
-0.05 0 0.05 0.1 0.15 0.2 0.25 0.3
Output Voltage (V)
0
0.25
0.5
0.75
1
Output Current (A)
Output Current
Output V oltage
1Ωload is turned on at time = 0
Figure 2: Overload Operation.
RSET
(kΩ)
Current
Limit Typ
(mA)
Device Will
Not Current
Limit Below
(mA)
Device Always
Current Limits
Below (mA)
40.2 225 169 281
30.9 300 225 375
24.9 350 263 438
22.1 425 319 531
19.6 450 338 563
17.8 525 394 656
16.2 600 450 750
14.7 675 506 844
13 700 525 875
10.5 1000 750 1250
8.87 1100 825 1375
7.5 1325 994 1656
6.81 1600 1200 2000
6.04 1925 1444 2406
5.49 1950 1463 2438
4.99 2100 1575 2625
4.64 2350 1763 2938
Table 1: 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 18kΩ. 17.8kΩ is a standard value
that is a little less than 18kΩ but very close. The chart
reads approximately 0.525A as a typical ILIM value for
17.8kΩ. Multiplying 0.525A by 0.75 and 1.25 shows that
the AAT4610B will limit the load current to greater than
0.394A but less than 0.656A.
Operation in Current Limit
When a heavy load is applied to the output of the
AAT4610B, the load current is limited to the value of ILIM
determined by RSET (see Figure 2). Since the load is
demanding more current than ILIM, the voltage at the
output drops. This causes the AAT4610B to dissipate a
larger than normal quantity of power, and its die tem-
perature to increase. When the die temperature exceeds
an over-temperature limit, the AAT4610B will shut down
until is has cooled sufficiently, at which point it will
startup again. The AAT4610B 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.
Enable Input
In many systems, power planes are controlled by inte-
grated circuits which run at lower voltages than the
power plane itself. The enable input ON of the AAT4610B
has low and high threshold voltages that accommodate
this condition. The threshold voltages are compatible
with 5V TTL and 2.5V to 5V CMOS.
Reverse Voltage
The AAT4610B 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 AAT4610B.
AAT4610B
Current Limited Load SwitchSmartSwitchTM
PRODUCT DATASHEET
10 4610B.2009.09.1.1
www.analogictech.com
Ordering Information
Package Enable Marking1Part Number (Tape and Reel)2
SOT23-5 ON (active high) 8FXYY AAT4610BIGV-1-T1
SC70JW-8 ON (active high) 8GXYY AAT4610BIJS-1-T1
SOT23-5 ON (active low) B9XYY AAT4610BIGV-T1
SC70JW-8 ON (active low) B8XYY AAT4610BIJS-T1
All AnalogicTech products are offered in Pb-free packaging. The term “Pb-free” means semiconductor
products that are in compliance with current RoHS standards, including the requirement that lead not
exceed 0.1% by weight in homogeneous materials. For more information, please visit our website at
http://www.analogictech.com/aboutus/quality.php.
Package Information
SOT23-5
4
°
±
4
°
0.15
±
0.07
0.45
±
0.15 0.10 BSC
1.20
±
0.25
1.575
±
0.125
2.80
±
0.20
0.40
±
0.10
0.60 REF
2.85
±
0.15
1.90 BSC
0.95
BSC
1.10
±
0.20
10
°
±
5
°
GAUGE PLANE
0.075
±
0.075
0.60 REF
All dimensions in millimeters.
1. XYY = assembly and date code.
2. Sample stock is generally held on part numbers listed in BOLD.
AAT4610B
Current Limited Load SwitchSmartSwitchTM
PRODUCT DATASHEET
4610B.2009.09.1.1 11
www.analogictech.com
Advanced Analogic Technologies, Inc.
3230 Scott Boulevard, Santa Clara, CA 95054
Phone (408) 737-4600
Fax (408) 737-4611
© Advanced Analogic Technologies, Inc.
AnalogicTech cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in an AnalogicTech product. No circuit patent licenses, copyrights, mask work rights, or other intellectual
property rights are implied. AnalogicTech reserves the right to make changes to their products or specifi cations or to discontinue any product or service without notice. Except as provided in AnalogicTech’s terms and
conditions of sale, AnalogicTech assumes no liability whatsoever, and AnalogicTech disclaims any express or implied warranty relating to the sale and/or use of AnalogicTech products including liability or warranties
relating to fi tness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right. In order to minimize risks associated with the customer’s applications, adequate
design and operating safeguards must be provided by the customer to minimize inherent or procedural hazards. Testing and other quality control techniques are utilized to the extent AnalogicTech deems necessary to
support this warranty. Specifi c testing of all parameters of each device is not necessarily performed. AnalogicTech and the AnalogicTech logo are trademarks of Advanced Analogic Technologies Incorporated. All other
brand and product names appearing in this document are registered trademarks or trademarks of their respective holders.
SC70JW-8
0.225
±
0.075
0.45
±
0.10
0.05
±
0.05
2.10
±
0.30
2.00
±
0.20
7
°
±
3
°
4
°
±
4
°
1.75
±
0.10
0.85
±
0.15
0.15
±
0.05
1.10 MAX
0.100
2.20
±
0.20
0.048REF
0.50 BSC 0.50 BSC 0.50 BSC
All dimensions in millimeters.
