AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
PRODUCT DATASHEET
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General Description
The AAT4280A SmartSwitch is a member of AnalogicTech’s
Application Specific Power MOSFET™ (ASPM™) product
family. The AAT4280A is a P-channel MOSFET power
switch designed for high-side load switching applications.
The device has a typical RDS(ON) of 80mΩ, allowing
increased load switch power handling capacity. The device
is available in three different versions with flexible turn-on
and turn-off characteristics — from very fast to slew rate
limited. The standard AAT4280A (-1) version has a slew
rate limited turn-on load switch and is functionally com-
patible with the AAT4250 device, while offering superior
RDS(ON) characteristics. The AAT4280A (-2) version fea-
tures fast load switch turn-on capabilities, typically less
than 500ns turn-on and 3μs turn-off times. The AAT4280A
(-3) variation offers a shutdown load discharge circuit to
rapidly turn off a load circuit when the switch is disabled.
The AAT4280A (-4) version features the slowest load
switch turn-on capability, typically greater than 4.0ms
turn-on time. All AAT4280A load switch versions operate
with an input voltage ranging from 1.5V to 5.5V, making
them ideal for both 3V and 5V systems. Input logic levels
are TTL and 2.5V to 5V CMOS compatible. The quiescent
supply current is very low, typically 25nA.
The AAT4280A is available in the Pb-free 8-pin SC70JW,
6-pin SOT23, and WLCSP-5 packages and is specified
over the -40°C to +85°C temperature range.
Features
• 1.5V to 5.5V Input Voltage Range
• Very Low RDS(ON), Typically 80mΩ (5V)
• Slew Rate Limited Turn-On Time Options
▪ 4.5ms
▪ 1ms
▪ 0.5μs
▪ 100μs
• Fast Shutdown Load Discharge Option
• Low Quiescent Current
▪ 25nA (typ)
• TTL/CMOS Input Logic Level
• Temperature Range: -40ºC to +85°C
• 3kV ESD Rating
• SC70JW-8, SOT23-6, and WLCSP-5 Packages
Applications
• Cellular Telephones
• Digital Still Cameras
• Hot Swap Supplies
• LCD Panels
• Notebook Computers
• Personal Communication Devices
• Personal Digital Assistants (PDAs)
Typical Application
AAT4280A
COUT
0.1µF
CIN
1µF
OUTIN
GND
VOUT
GND
GND
VIN
ON/OFF
GND
IN
ON
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Slew Rate Controlled Load SwitchSmartSwitchTM
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Pin Descriptions
Pin #
Symbol Function
SC70JW-8 SOT23-6 WLSCP-5
1, 5, 6, 7, 8 4, 6 1, 4 IN This pin is the input to the P-channel MOSFET source. Bypass to ground
through a 1.0μF capacitor.
2 1 5 OUT This pin is the P-channel MOSFET drain connection. Bypass to ground
through a 0.1μF capacitor.
332
ON/OFF Enable input.
4 5 3 GND Ground connection.
Pin Configuration
SC70JW-8 SOT23-6 WLCSP-5
(Top View) (Top View) (Top View)
OUT
ON/OFF
GND
IN
IN
IN
IN
IN 1
2
3
45
6
7
8
GND
IN
GND
IN
ON/OFF
OUT
1
2
34
5
6
IN OUT
45
IN
GND
ON/OFF
1
3
2
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Slew Rate Controlled Load SwitchSmartSwitchTM
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Slew Rate Controlled Load SwitchSmartSwitchTM
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Selector Guide
Part Number Slew Rate (typ) Active Pull Down Enable
AAT4280A-1 1ms Active High
AAT4280A-2 0.5μs Active High
AAT4280A-3 100μs9Active High
AAT4280A-4 4.5ms 9Active High
Absolute Maximum Ratings1
TA = 25°C, unless otherwise noted.
Symbol Description Value Units
VIN IN to GND -0.3 to 6 V
VON ON/OFF to GND -0.3 to 6 V
VOUT OUT to GND -0.3 to VIN + 0.3 V
IMAX Maximum Continuous Switch Current 2.3 A
IDM Maximum Pulsed Current IN ≥ 2.5V 6 A
IN < 2.5V 3 A
TJOperating Junction Temperature Range -40 to 150 °C
TSStorage Temperature Range -65 to 150 °C
TLEAD Maximum Soldering Temperature (at leads) 300 °C
VESD ESD Rating2 - HBM 3000 V
Thermal Characteristics
Symbol Description Package Value Units
PDMaximum Power Dissipation
SC70JW-83,4 714
mWSOT23-63,5 833
WLCSP-53,6 352
θJA Thermal Resistance
SC70JW-8 140
°C/WSOT23-6 120
WLCSP-5 284
1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at condition 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 an FR4 board; for the WLCSP package, use the NSMD (non-solder mask defined) pad style for tighter control on the copper etch process.
4. Derate 7.14mW/°C above 25°C.
5. Derate 8.33mW/°C above 25°C.
6. Derate 3.52mW/°C above 25°C.
AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
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Slew Rate Controlled Load SwitchSmartSwitchTM
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Electrical Characteristics
Unless otherwise noted, VIN = 5V, TA = -40°C to +85°C; typical values are TA = 25°C.
Symbol Description Conditions Min Typ Max Units
AAT4280A All Versions
VIN Operation Voltage 1.5 5.5 V
IQQuiescent Current ON/OFF = Active 1 μA
IQ(off) Off Supply Current ON/OFF = Inactive, OUT = Open 1 μA
ISD(off) Off Switch Current ON/OFF = Inactive, VOUT = 0 1 μA
RDS(on) On Resistance
VIN = 5V, TA = 25°C 80 120
mΩ
VIN = 4.2V, TA = 25°C 85 130
VIN = 3V, TA = 25°C 100 150
VIN = 1.8V, TA = 25°C 160 250
VIN = 1.5V, TA = 25°C 200 300
TCRDS On Resistance Temperature Coeffi cient 2800 ppm/°C
VIL ON/OFF Input Logic Low Voltage VIN = 1.5V to 5.5V10.4 V
VIH ON/OFF Input Logic High Voltage
VIN = 1.5V to 2.7V 1.4
V
VIN = 2.7V to 4.2V 2
VIN = 4.2V to 5.5V 2.4
VIN = 3.3V 1.8
ISINK ON/OFF Input Leakage VON/OFF = 5.5V 1 μA
AAT4280A-1
TD(ON) Output Turn-On Delay VIN = 5V, RLOAD = 10Ω, TA = 25°C 20 40 μs
TON Output Turn-On Rise Time VIN = 5V, RLOAD = 10Ω, TA = 25°C 1000 1500 μs
TD(OFF) Output Turn-Off Delay Time VIN = 5V, RLOAD = 10Ω, TA = 25°C 4 10 μs
AAT4280A-2
TD(ON) Output Turn-On Delay VIN = 5V, RLOAD = 10Ω, TA = 25°C 0.5 2 μs
TON Output Turn-On Rise Time VIN = 5V, RLOAD = 10Ω, TA = 25°C 0.5 1 μs
TD(OFF) Output Turn-Off Delay Time VIN = 5V, RLOAD = 10Ω, TA = 25°C 4 10 μs
AAT4280A-3
TD(ON) Output Turn-On Delay VIN = 5V, RLOAD = 10Ω, TA = 25°C 20 40 μs
TON Output Turn-On Rise Time VIN = 5V, RLOAD = 10Ω, TA = 25°C 100 150 μs
TD(OFF) Output Turn-Off Delay Time VIN = 5V, RLOAD = 10Ω, TA = 25°C 4 10 μs
RPD Output Pull-Down Resistance During OFF ON/OFF = Inactive, TA = 25°C 150 250 Ω
AAT4280A-4
TD(ON) Output Turn-On Delay Time VIN = 3.3V, RLOAD = 10Ω, TA = 25°C 20 40 μs
TON Output Turn-On Rise Time VIN = 3.3V, RLOAD = 10Ω, TA = 25°C 2000 4500 μs
TD(OFF) Output Turn-OFF Delay Time VIN = 3.3V, RLOAD = 10Ω, TA =25°C 4 10 μs
RPD Output Pull-Down Resistance During OFF ON/OFF = Inactive, TA = 25°C 150 250 Ω
1. For VIN outside this range, consult typical ON/OFF threshold curve.
AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
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Slew Rate Controlled Load SwitchSmartSwitchTM
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Typical Characteristics
Unless otherwise noted, VIN = 5V, TA = 25°C.
Quiescent Current vs. Temperature
Temperature (°
°
C)
Quiescent Current (nA)
0
10
20
30
40
50
-40 -20 0 20 40 60 80 100
RDS(ON) vs. Input Voltage
Input Voltage (V)
RDS(ON) (mΩ
Ω
)
70
90
110
130
150
170
190
210
230
250
270
1.5 1.8 2.0 2.3 2.5 2.8 3.8 4.83.0 3.3 4.3 5.33.5 4.0 4.5 5.0 5.5
2A
1A
500mA
100mA
RDS(ON) vs. Temperature
40
50
60
70
80
90
100
110
120
-40 -20 0 20 40 60 80 100
Temperature (
°
C)
RDS(ON) (m
Ω
)
VIN = 5V
VIN = 3V
ON/OFF Threshold vs. Input Voltage
Input Voltage (V)
ON/OFF Threshold (V)
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
1.4 1.9 2.4 2.9 3.4 3.9 4.4 4 5.4
VIH
VIL
Off-Switch Current vs. Temperature
0.001
0.010
0.100
1.000
-40 -20 0 20 40 60 80 100
Temperature (
°
C)
Off-Switch Current (
μ
A)
AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
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Slew Rate Controlled Load SwitchSmartSwitchTM
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Typical Characteristics—AAT4280A-1
Unless otherwise noted, VIN = 5V, TA = 25°C.
AAT4280A-1 Turn-On
(VIN = 3V; RL = 6
Ω
)
Time (500
μ
s/div)
ON/OFF (5V/div)
VOUT (2V/div)
IIN (200mA/div)
AAT4280A-1 Turn-On
(VIN = 5V; RL = 10
Ω
)
Time (500
μ
s/div)
ON/OFF (5V/div)
VOUT (2V/div)
IIN (200mA/div)
AAT4280A-1 Turn-Off
(VIN = 3V; RL = 6
Ω
)
Time (10
μ
s/div)
ON/OFF (5V/div)
VOUT (2V/div)
IIN (200mA/div)
AAT4280A-1 Turn-Off
(VIN = 5V; RL = 10
Ω
)
Time (10
μ
s/div)
ON/OFF (5V/div)
VOUT (2V/div)
IIN (200mA/div)
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Slew Rate Controlled Load SwitchSmartSwitchTM
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Slew Rate Controlled Load SwitchSmartSwitchTM
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Typical Characteristics—AAT4280A-2
Unless otherwise noted, VIN = 5V, TA = 25°C.
AAT4280A-2 Turn-On
(VIN = 3V; RIN = 6
Ω
)
Time (5
μ
s/div)
ON/OFF (5V/div)
VOUT (2V/div)
IIN (200mA/div)
AAT4280A-2 Turn-On
(VIN = 5V; RL = 10
Ω
)
Time (5
μ
s/div)
ON/OFF (5V/div)
VOUT (2V/div)
IIN (200mA/div)
AAT4280A-2 Turn-Off
(VIN = 3V; RL = 6
Ω
)
Time (5
μ
s/div)
ON/OFF (5V/div)
VOUT (2V/div)
IIN (200mA/div)
AAT4280A-2 Turn-Off
(VIN = 5V; RL = 10
Ω
)
Time (5
μ
s/div)
ON/OFF (5V/div)
VOUT (2V/div)
IIN (200mA/div)
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Slew Rate Controlled Load SwitchSmartSwitchTM
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Slew Rate Controlled Load SwitchSmartSwitchTM
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Typical Characteristics—AAT4280A-3
Unless otherwise noted, VIN = 5V, TA = 25°C.
AAT4280A-3 Turn-On
(VIN = 3V; RL = 6
Ω
)
Time (50
μ
s/div)
ON/OFF (5V/div)
VOUT (2V/div)
IIN (200mA/div)
AAT4280A-3 Turn-On
(VIN = 5V; RL = 10
Ω
)
Time (50
μ
s/div)
ON/OFF (5V/div)
VOUT (2V/div)
IIN (200mA/div)
AAT4280A-3 Turn-Off
(VIN = 3V; RL = 6
Ω
)
Time (5
μ
s/div)
ON/OFF (5V/div)
VOUT (2V/div)
IIN (200mA/div)
AAT4280A-3 Turn-Off
(VIN = 5V; RL = 10
Ω
)
Time (5
μ
s/div)
ON/OFF (5V/div)
VOUT (2V/div)
IIN (200mA/div)
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Slew Rate Controlled Load SwitchSmartSwitchTM
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Slew Rate Controlled Load SwitchSmartSwitchTM
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Typical Characteristics—AAT4280A-4
Unless otherwise noted, VIN = 5V, TA = 25°C.
AAT4280A-4 Turn-On
(VIN = 3V; RL = 10Ω
Ω
)
Time (2ms/div)
EN (2V/div)
VOUT (2V/div)
IIN (200mA/div)
AAT4280A-4 Turn-On
(VIN = 5V; RL = 10Ω
Ω
)
Time (2ms/div)
EN (5V/div)
VOUT (5V/div)
IIN (500mA/div)
AAT4280A-4 Turn-Off
(VIN = 3.3V; RL = 10W
W
)
Time (10µs/div)
EN (2V/div)
VOUT (2V/div)
IIN (200mA/div)
AAT4280A-4 Turn-Off
(VIN = 5V; RL = 10Ω
Ω
)
Time (10µs/div)
EN (5V/div)
VOUT (5V/div)
IIN (500mA/div)
AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
PRODUCT DATASHEET
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AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
PRODUCT DATASHEET
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Functional Description
The AAT4280A is a family of flexible P-channel MOSFET
power switches designed for high-side load switching
applications. There are three versions of the AAT4280A
with different turn-on and turn-off characteristics to
choose from, depending upon the specific requirements
of an application. The first version, the AAT4280A-1, has
a moderate turn-on slew rate feature, which reduces
inrush current when the MOSFET is turned on. This func-
tion allows the load switch to be implemented with either
a small input capacitor or no input capacitor at all.
During turn-on slewing, the current ramps linearly until
it reaches the level required for the output load condi-
tion. The proprietary turn-on current control method
works by careful control and monitoring of the MOSFET
gate voltage. When the device is switched ON, the gate
voltage is quickly increased to the threshold level of the
MOSFET. Once at this level, the current begins to slew as
the gate voltage is slowly increased until the MOSFET
becomes fully enhanced. Once it has reached this point,
the gate is quickly increased to the full input voltage and
RDS(ON) is minimized.
The second version, the AAT4280A-2, is a very fast
switch intended for high-speed switching applications.
This version has no turn-on slew rate control and no
special output discharge features.
The third switch version, the AAT4280A-3, has the addition
of a minimized slew rate limited turn-on function and a
shutdown output discharge circuit to rapidly turn off a load
when the load switch is disabled through the ON/OFF pin.
The final switch version, the AAT4280A-4, features a very
slow turn-on slew rate with a typical value of 4.5ms for
LCD panel applications.
All versions of the AAT4280A operate with input voltages
ranging from 1.5V to 5.5V. All versions of this device
have extremely low operating current, making them
ideal for battery-powered applications. The ON/OFF con-
trol pin is TTL compatible and will also function with 2.5V
to 5V logic systems, making the AAT4280A an ideal
level-shifting load switch.
Functional Block Diagram
Level
Shift
IN
ON/OFF
OU
T
GND
Turn-On
Slew Rate
Control
*
*AAT4280A-3 and -4 only
AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
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Applications Information
Input Capacitor
A 1μF or larger capacitor is typically recommended for
CIN in most applications. A CIN capacitor is not required
for basic operation; however, CIN is useful in preventing
load transients from affecting upstream circuits. CIN
should be located as close to the device VIN pin as practi-
cally possible. Ceramic, tantalum, or aluminum electro-
lytic capacitors may be selected for CIN. There is no
specific capacitor ESR requirement for CIN; however, for
higher current operation, ceramic capacitors are recom-
mended for CIN due to their inherent capability over tan-
talum capacitors to withstand input current surges from
low impedance sources, such as batteries in portable
devices.
Output Capacitor
For proper slew operation, a 0.1μF capacitor or greater
between VOUT and GND is recommended. The output
capacitor has no specific capacitor type or ESR require-
ment. If desired, COUT may be increased without limit to
accommodate any load transient condition without
adversely affecting the device turn-on slew rate time.
Enable Function
The AAT4280A features an enable / disable function. This
pin (ON/OFF) is compatible with both TTL or CMOS logic.
Reverse Output-to-Input
Voltage Conditions and Protection
Under normal operating conditions, a parasitic diode exists
between the output and input of the load switch. The input
voltage should always remain greater than the output load
voltage, maintaining a reverse bias on the internal para-
sitic diode. Conditions where VOUT might exceed VIN should
be avoided since this would forward bias the internal para-
sitic diode and allow excessive current flow into the VOUT
pin and possibly damage the load switch.
In applications where there is a possibility of VOUT
exceeding VIN for brief periods of time during normal
operation, the use of a larger value CIN capacitor is
highly recommended. A larger value of CIN with respect
to COUT will effect a slower CIN decay rate during shut-
down, thus preventing VOUT from exceeding VIN. In appli-
cations where there is a greater danger of VOUT exceeding
VIN for extended periods of time, it is recommended to
place a Schottky diode from VIN to VOUT (connecting the
cathode to VIN and anode to VOUT). The Schottky diode
forward voltage should be less than 0.45V.
Thermal Considerations and
High Output Current Applications
The AAT4280A is designed to deliver a continuous output
load current. The limiting characteristic for maximum
safe operating output load current is package power dis-
sipation. In order to obtain high operating currents,
careful device layout and circuit operating conditions
need to be taken into account.
The following discussions will assume the load switch is
mounted on a printed circuit board utilizing the minimum
recommended footprint, as stated in the Layout
Considerations section of this datasheet.
At any given ambient temperature (TA), the maximum
package power dissipation can be determined by the fol-
lowing equation:
PD(MAX)
[TJ(MAX) - TA]
θJA
=
Constants for the AAT4280A are maximum junction tem-
perature, TJ(MAX) = 125°C, and package thermal resis-
tance, ΘJA = 120°C/W. Worst case conditions are calcu-
lated at the maximum operating temperature where TA =
85°C. Typical conditions are calculated under normal
ambient conditions where TA = 25°C. At TA = 85°C, PD(MAX)
= 333mW. At TA = 25°C, PD(MAX) = 833mW.
The maximum continuous output current for the AAT4280A
is a function of the package power dissipation and the RDS
of the MOSFET at TJ(MAX). The maximum RDS of the MOSFET
at TJ(MAX) is calculated by increasing the maximum room
temperature RDS by the RDS temperature coefficient. The
temperature coefficient (TC) is 2800ppm/°C. Therefore,
MAX RDS125°C = RDS25°C · (1 + TC · ΔT)
MAX RDS125°C = 120mΩ · (1 + 0.0028 ·
(125°C - 25°C)) = 154mΩ
For maximum current, refer to the following equation:
IOUT(MAX)
PD(MAX)
RDS
<
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For example, if VIN = 5V, RDS(MAX) = 154mΩ and TA =
25°C, IOUT(MAX) = 2.3A. If the output load current were to
exceed 2.3A or if the ambient temperature were to
increase, the internal die temperature would increase
and the device would be damaged.
Higher peak currents can be obtained with the AAT4280A.
To accomplish this, the device thermal resistance must
be reduced by increasing the heat sink area or by oper-
ating the load switch in a duty-cycle manner.
High Peak Output Current Applications
Some applications require the load switch to operate at
a continuous nominal current level with short duration,
high-current peaks. The duty cycle for both output cur-
rent levels must be taken into account. To do so, first
calculate the power dissipation at the nominal continu-
ous current level, and then add in the additional power
dissipation due to the short duration, high-current peak
scaled by the duty factor.
For example, a 4V system using an AAT4280A operates
at a continuous 100mA load current level and has short
2A current peaks, as in a GSM application. The current
peak occurs for 576μs out of a 4.61ms period.
First, the current duty cycle is calculated:
% Peak Duty Cycle: X/100 = 576μs/4.61ms
% Peak Duty Cycle = 12.5%
The load current is 100mA for 87.5% of the 4.61ms
period and 2A for 12.5% of the period. Since the
Electrical Characteristics do not report RDS(MAX) for 4V
operation, it must be calculated approximately by con-
sulting the chart of RDS(ON) vs. VIN. The RDS reported for 5V
can be scaled by the ratio seen in the chart to derive the
RDS for a 4V VIN: 120mΩ · 87mΩ /80mΩ = 130mΩ.
De-rated for temperature: 130mΩ · (1 + 0.0028 · (125°C
- 25°C)) = 166mΩ. The power dissipation for a 100mA
load is calculated as follows:
PD(MAX) = IOUT2 · RDS
PD(100mA) = (100mA)2 · 166mW
PD(100mA) = 1.66mW
PD(87.5%D/C) = %DC · PD(100mA)
PD(87.5%D/C) = 0.875 · 1.66mW
PD(87.5%D/C) = 1.45mW
The power dissipation for 100mA load at 87.5% duty
cycle is 1.45mW. Now the power dissipation for the
remaining 12.5% of the duty cycle at 2A is calculated:
PD(MAX) = IOUT2 · RDS
PD(2A) = (2A)2 · 166mΩ
PD(2A) = 664mW
PD(12.5%D/C) = %DC · PD(2A)
PD(12.5%D/C) = 0.125 · 664mΩ
PD(12.5%D/C) = 83mW
The power dissipation for 2A load at 12.5% duty cycle is
83mW. Finally, the two power figures are summed to
determine the total true power dissipation under the
varied load:
PD(total) = PD(100mA) + PD(2A)
PD(total) = 1.45mW + 83mW
PD(total) = 84.5mW
The maximum power dissipation for the AAT4280A oper-
ating at an ambient temperature of 85°C is 333mW. The
device in this example will have a total power dissipation
of 84.5mW. This is well within the thermal limits for safe
operation of the device; in fact, at 85°C, the AAT4280A
will handle a 2A pulse for up to 50% duty cycle. At lower
ambient temperatures, the duty cycle can be further
increased.
Printed Circuit Board
Layout Recommendations
For proper thermal management and to take advantage
of the low RDS(ON) of the AAT4280A, a few circuit board
layout rules should be followed: VIN and VOUT should be
routed using wider than normal traces, and GND should
be connected to a ground plane. To maximize package
thermal dispation and power handling capacity of the
AAT4280A SC70JW-8 package, the ground plane area
connected to the ground pins should be made as large
as possible. For best performance, CIN and COUT should
be placed close to the package pins.
Evaluation Board Layout
The AAT4280A evaluation layout follows the printed cir-
cuit board layout recommendations and can be used for
good applications layout. Refer to Figures 1 through 3.
Note: Board layout shown is not to scale.
AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
PRODUCT DATASHEET
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AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
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Figure 1: AAT4280A SC70JW-8 Package Figure 2: AAT4280A SC70JW-8 Package
Evaluation Board Component Side Layout. Evaluation Board Solder Side Layout.
IN
IN
AAT4280A
VIN
ON/OFF
GND
IN
IN
IN
OUT
C1
1μF
VOUT
C2
0.1μF
1
6
54
3
2
8
7
EN
Figure 3: AAT4280A SC70JW-8 Package Evaluation Board Schematic.
AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
PRODUCT DATASHEET
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AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
PRODUCT DATASHEET
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Figure 4: AAT4280A SOT23-6 Package Figure 5: AAT4280A SOT23-6 Package
Evaluation Board Component Side Layout. Evaluation Board Solder Side Layout.
GND
IN
AAT4280A
VIN ON/OFF
IN OUT
C1
1μF
VOU
C2
0.1μF
4
16
5
3
2
EN
GND
Figure 6: AAT4280A SOT23-6 Package Evaluation Board Schematic.
AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
PRODUCT DATASHEET
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AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
PRODUCT DATASHEET
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Figure 7: AAT4280A WLCSP-5 Package Figure 8: AAT4280A WLCSP-5 Package
Evaluation Board Component Side Layout. Evaluation Board Solder Side Layout.
GND
IN
AAT4280A
VIN
VOUT
ON/OFF
IN OUT
C1
1μF
C2
0.1μF
EN
12
3
5
4
Figure 9: AAT4280A WLCSP-5 Package Evaluation Board Schematic.
AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
PRODUCT DATASHEET
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Slew Rate Controlled Load SwitchSmartSwitchTM
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Ordering Information
Device Option Package Marking1Part Number (Tape and Reel)2
AAT4280A-1 SC70JW-8 NDXYY AAT4280AIJS-1-T1
AAT4280A-2 SC70JW-8 NEXYY AAT4280AIJS-2-T1
AAT4280A-3 SC70JW-8 NFXYY AAT4280AIJS-3-T1
AAT4280A-4 SC70JW-8 3EXYY AAT4280AIJS-4-T1
AAT4280A-4 SOT23-6 3LXYY AAT4280AIGU-4-T1
AAT4280A-3 WLCSP-5 4PYW3AAT4280AIUV-3-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/about/quality.aspx.
Package Information
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.
1. XYY = assembly and date code.
2. Sample stock is generally held for part numbers listed in BOLD.
3. YW = year code + week code.
AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
PRODUCT DATASHEET
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AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
PRODUCT DATASHEET
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SOT23-6
1.90 BSC
0.95 BSC
0.45
±
0.15 0.10 BSC
2.85
±
0.15
0.075
±
0.075
0.40
±
0.10
×
6
1.575
±
0.125
1.20
±
0.25
1.10
±
0.20 2.80
±
0.20
4
°
±
4
°
10
°
±
5
°
0.15
±
0.07
GAUGE PLANE
0.60 REF
AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
PRODUCT DATASHEET
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AAT4280A
Slew Rate Controlled Load SwitchSmartSwitchTM
PRODUCT DATASHEET
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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.
WLSCP-5
0.725
±
0.025
0.400 BSC
60°
0.400 BSC
0.945
±
0.025
0.693 BSC
0.337
±
0.025
0.120
±
0.018
0.250
0.050
0.100
Line_1 Line_2
ø 0.1 (Ref.)
Pin 1 indication
Bottom View Top View
Side View
0.457
±
0.043
0.190
±
0.029
End View
All dimensions in millimeters.