AAT4282A-2 [ANALOGICTECH]

Slew Rate Controlled Load Switch; 压摆率受控负载开关
AAT4282A-2
型号: AAT4282A-2
厂家: ADVANCED ANALOGIC TECHNOLOGIES    ADVANCED ANALOGIC TECHNOLOGIES
描述:

Slew Rate Controlled Load Switch
压摆率受控负载开关

开关
文件: 总13页 (文件大小:603K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
PRODUCT DATASHEET  
AAT4282A  
SmartSwitchTM  
Slew Rate Controlled Load Switch  
General Description  
Features  
TheAAT4282ASmartSwitchisamemberofAnalogicTech’s  
Application Specific Power MOSFET™ (ASPM™) product  
family. The AAT4282A is a dual P-channel MOSFET power  
switch designed for high-side load-switching applications.  
Each MOSFET has a typical RDS(ON) of 60mΩ, allowing  
increased load switch current handling capacity with a low  
forward voltage drop. The device is available in three dif-  
ferent versions with flexible turn-on and turn-off charac-  
teristics – from very fast to slew-rate limited. The stan-  
dard 4282A (-1) version has a slew-rate limited turn-on  
load switch. The AAT4282A (-2) version features fast  
turn-on capability, typically less than 500ns turn-on and  
3μs turn-off times. The AAT4282A (-3) variation offers a  
shutdown load discharge circuit to rapidly turn off a load  
circuit when the switch is disabled. An additional feature  
is a slew-rate selector pin which can switch between fast  
and slow slew rate.  
• VIN Range: 1.5V to 6.5V  
• Low RDS(ON)  
60mΩ Typical @ 5V  
140mΩ Typical @ 1.5V  
• Slew Rate Turn-On Time Options  
1ms  
0.5μs  
100μs  
• Fast Shutdown Load Discharge Option  
• Low Quiescent Current  
Typically 1μA  
• TTL/CMOS Input Logic Level  
Temperature Range -40°C to 85°C  
• FTDFN22-8 Package  
Applications  
• Cellular Telephones  
• Digital Still Cameras  
• Hotswap Supplies  
• Notebook Computers  
• PDA Phones  
All the AAT4282A load switch versions are designed to  
operate from 1.5V up to 6.5V, making them ideal for  
both 3V and 5V systems. Input logic levels are TTL and  
2.5V to 5V CMOS compatible. The quiescent supply cur-  
rent is a very low 1μA.  
• PDAs  
• PMPs  
• Smartphones  
The AAT4282A is available in the Pb-free, low profile  
2.0x2.0mm FTDFN22-8 package and is specified over  
the -40 to 85°C temperature range.  
Typical Application  
OUTA  
OUTB  
INA  
INB  
INA  
OUTA  
OUTB  
INB  
ON/OFF  
AAT4282A  
ENA  
ENB  
FAST  
ON/OFF  
C1  
1μF  
C2  
1μF  
C3  
0.1μF  
C4  
0.1μF  
FAST/SLOW  
GND  
N/C  
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1
PRODUCT DATASHEET  
AAT4282A  
SmartSwitchTM  
Slew Rate Controlled Load Switch  
Pin Descriptions  
Pin #  
Symbol Function  
This is the pin to the P-channel MOSFET source for Switch A. Bypass to ground through a 1μF capacitor.  
INA is independent of INB  
Active-High Enable Input A. A logic low turns the switch off and the device consumes less than 1μA of cur-  
rent. Logic high resumes normal operation.  
Active-High Enable Input B. A logic low turns the switch off and the device consumes less than 1μA of cur-  
rent. Logic high resumes normal operation.  
This is the pin to the P-channel MOSFET source for Switch B. Bypass to ground through a 1μF capacitor.  
INB is independent of INA.  
1
INA  
ENA  
ENB  
INB  
2
3
4
5
6
7
8
OUTB  
GND  
FAST  
OUTA  
This is the pin to the P-channel MOSFET drain connection. Bypass to ground through a 0.1μF capacitor.  
Ground connection  
Active-high input Switches between FAST (Logic H) and SLOW (Logic L) Slew rate  
This is the pin to the P-channel MOSFET drain connection. Bypass to ground through a 0.1μF capacitor.  
Pin Configuration  
FTDFN22-8  
(Top View)  
1
2
3
4
8
7
6
5
INA  
ENA  
ENB  
INB  
OUTA  
FAST  
GND  
OUTB  
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4282A.2008.02.1.2  
PRODUCT DATASHEET  
AAT4282A  
SmartSwitchTM  
Slew Rate Controlled Load Switch  
Selector Guide  
Slew Rate (Typ)  
Part Number  
FAST (H)  
SLOW (L)  
Active Pull-Down  
Enable  
AAT4282A-1*  
AAT4282A-2*  
AAT4282A-3  
1ms  
0.5μs  
100μs  
NO  
NO  
YES  
Active High  
Active High  
Active High  
1ms  
Absolute Maximum Ratings1  
Symbol  
Description  
Value  
Units  
VIN  
VEN, FAST  
VOUT  
IN to GND  
EN, FAST to GND  
OUT to GND  
Maximum Continuous Switch Current  
-0.3 to 7  
-0.3 to 7  
-0.3 to VIN + 0.3  
3
V
V
V
IMAX  
A
IDM  
TJ  
TLEAD  
VESD  
Maximum Pulsed Current (Duty Cycle 10%)  
Operating Junction Temperature Range  
Maximum Soldering Temperature (at leads)  
ESD Rating2 – HBM  
5.5  
-40 to 150  
300  
A
°C  
°C  
V
4000  
Thermal Characteristics3  
Symbol  
Description  
Value  
Units  
θJA  
PD  
Thermal Resistance  
Maximum Power Dissipation  
70  
1.78  
°C/W  
W
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 AAT4282A demo board in still 25°C air.  
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PRODUCT DATASHEET  
AAT4282A  
SmartSwitchTM  
Slew Rate Controlled Load Switch  
Electrical Characteristics1  
VIN = 5V, TA = -40 to 85°C unless otherwise noted. Typical values are at TA = 25°C. Per channel.  
Symbol Description  
AAT4282A All Versions  
Conditions  
Min Typ Max Units  
VIN  
IQ  
IQ(OFF)  
ISD(OFF)  
Operation Voltage  
Quiescent Current  
Off Supply Current  
Off Switch Current  
1.5  
6.5  
1.0  
1.0  
1.0  
V
ON/OFF = ACTIVE, FAST = VIN, IOUT = 0  
ON/OFF = Inactive, OUT = Open  
ON/OFF = GND, VOUT = 0  
VIN = 6.5V  
VIN = 5V  
VIN = 4.2V  
VIN = 3.0V  
VIN = 1.80V  
VIN = 1.5V  
μA  
μA  
μA  
56  
60  
65  
130  
140  
160  
230  
280  
RDS(ON)  
On-Resistance A or B  
mΩ  
76  
110  
140  
2800  
TCRRDS  
VIL  
VIH  
ISINK  
AAT4282A-12  
On Resistance Temperature Coefcient  
ON/OFF Input Logic Low Voltage  
ON/OFF Input Logic High Voltage  
ON/OFF Input Leakage  
ppm/°C  
VIN = 1.5V  
VIN = 5V  
VON/OFF = 5.5V  
0.4  
1.0  
40  
V
V
μA  
1.4  
TD(ON)  
TON  
TD(OFF)  
Output Turn-On Delay Time  
Turn-On Rise Time  
Output Turn-OFF Delay Time  
VIN = 5V, RLOAD =10Ω, TA =25°C  
VIN = 5V, RLOAD =10Ω, TA =25°C  
VIN = 5V, RLOAD =10Ω, TA =25°C  
20  
μs  
μs  
μs  
1000 1500  
4.0  
10  
AAT4282A-22  
TD(ON)  
TON  
TD(OFF)  
Output Turn-On Delay Time  
Turn-On Rise Time  
Output Turn-OFF Delay Time  
VIN = 5V, RLOAD =10Ω, TA =25°C  
VIN = 5V, RLOAD =10Ω, TA =25°C  
VIN = 5V, RLOAD =10Ω, TA =25°C  
0.5  
0.5  
4.0  
2
1.0  
10  
μs  
μs  
μs  
AAT4282A-3  
TD(ON)  
TON  
TON  
TD(OFF)  
RPD  
Output Turn-On Delay Time  
Turn-On Rise Time  
Turn-On Rise Time  
Output Turn-OFF Delay Time  
VIN = 5V, RLOAD =10Ω, TA =25°C  
20  
100  
1000 1500  
4.0  
40  
150  
μs  
μs  
μs  
μs  
Ω
VIN = 5V, RLOAD =10Ω, FAST = 5V, TA =25°C  
VIN = 5V, RLOAD =10Ω, FAST = 0V, TA =25°C  
VIN = 5V, RLOAD =10Ω, TA =25°C  
10  
250  
Output Pull-Down Resistance During OFF ON/OFF = Inactive, TA =25°C  
150  
1. The AAT4282A is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assured by design, characterization, and cor-  
relation with statistical process controls.  
2. Contact factory for other turn on and delay options.  
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PRODUCT DATASHEET  
AAT4282A  
SmartSwitchTM  
Slew Rate Controlled Load Switch  
Typical Characteristics  
VIN = 5V, TA = 25°C unless otherwise noted.  
Quiescent Current vs. Temperature  
(No Load; Single Switch)  
Quiescent Current vs. Input Voltage  
(No Load; Single Switch)  
12  
12  
10  
10  
8
8
6
4
2
0
VIN = 5V  
6
4
VIN = 3V  
2
0
-40  
-15  
10  
35  
60  
85  
0
1
2
3
4
5
6
Temperature (°C)  
Input Voltage (V)  
Off Supply Current vs. Temperature  
(No Load; EN = GND; VIN = 5V)  
Typical ON/OFF Threshold vs. Input Voltage  
1.3  
1.2  
1
0.9  
0.8  
0.7  
0.6  
0.5  
0.4  
0.3  
0.2  
0.1  
0
1.1  
V
IH  
1
V
IL  
0.9  
0.8  
0.7  
0.6  
1.5  
2
2.5  
3
3.5  
4
4.5  
5
5.5  
-40  
-15  
10  
35  
60  
85  
Temperature (°C)  
Input Voltage (V)  
On-Resistance vs. Temperature  
On-Resistance vs. Input Voltage  
100  
90  
80  
70  
60  
50  
40  
30  
20  
10  
0
220  
200  
180  
160  
140  
120  
100  
80  
VIN = 3V  
ISW = 2A  
VIN = 5V  
ISW = 100mA  
60  
40  
1.5  
2.5  
3.5  
4.5  
5.5  
6.5  
-40  
-15  
10  
35  
60  
85  
Temperature (°C)  
Input Voltage (V)  
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PRODUCT DATASHEET  
AAT4282A  
SmartSwitchTM  
Slew Rate Controlled Load Switch  
Typical Characteristics  
VIN = 5V, TA = 25ºC unless otherwise noted.  
Output Turn-On Delay Time  
(VINA/VENA = 5V; VINB/VENB = 3V; RLA = 10Ω; RLB = 20Ω)  
Output Turn-On Delay Time  
(VINA/VINB/VEN = 5V; RL = 10Ω)  
6
6
ENA  
ENA  
4
4
VOUT  
VOUT  
2
2
0
0
6
ENB  
4
4
ENB  
VOUT  
2
2
VOUT  
0
0
Time (50µs/div)  
Time (50µs/div)  
Output Turn-On Delay Time  
(VIN = 5V; RL = 10Ω)  
Output Turn-On Delay Time  
(VIN = 3V; RL = 20Ω)  
6
EN  
5
4
4
VOUT  
EN  
3
2
1
0
3
0.4  
0.2  
0
2
1
0
1
VOUT  
IIN  
0.5  
0
IIN  
Time (50µs/div)  
Time (50µs/div)  
Output Turn-On  
(RL = 10ΩΩ)  
Output Turn-On  
(VIN = 1.8V; RL = 10Ω)  
3.5  
3
7
EN  
6
5
4
3
2
1
0
VEN  
2.5  
2
VOUT (FAST = GND)  
1.5  
1
VOUT (FAST = GND)  
0.5  
0
VOUT (FAST = VIN)  
VOUT (FAST = VIN)  
-0.5  
Time (500µs/div)  
Time (200µs/div)  
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4282A.2008.02.1.2  
PRODUCT DATASHEET  
AAT4282A  
SmartSwitchTM  
Slew Rate Controlled Load Switch  
Typical Characteristics  
VIN = 5V, TA = 25ºC unless otherwise noted.  
Output Turn-Off Delay Time  
(VIN = 5V; RL = 10Ω)  
Output Turn-Off Delay Time  
(VIN = 3V; RL = 20Ω)  
6
5
4
3
2
1
0
1.2  
1
4
0.8  
0.6  
0.4  
0.2  
0
IIN  
VOUT  
3
2
1
0
IIN  
0.4  
0.2  
0
VOUT  
EN  
EN  
Time (5µs/div)  
Time (5µs/div)  
Output Turn-Off Delay Time  
(VIN = 1.8V; RL = 10Ω)  
3.5  
3
2.5  
2
1.5  
1
VOUT  
0.5  
0
VEN  
-0.5  
Time (5µs/div)  
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PRODUCT DATASHEET  
AAT4282A  
SmartSwitchTM  
Slew Rate Controlled Load Switch  
Functional Block Diagram  
OUTA  
INA  
Turn-On Slew  
Rate Control  
Level  
Shift  
*
ON/OFF A  
FAST/  
SLOW  
OUTB  
INB  
Turn-On Slew  
Rate Control  
Level  
Shift  
*
ON/OFF B  
GND  
* AAT4282A-3 version only.  
reached this point the gate is quickly increased to the full  
input voltage and the RDS(ON) is minimized.  
Functional Description  
The AAT4282A is a family of flexible dual P-channel  
MOSFET power switches designed for high-side load  
switching applications. There are three versions of the  
AAT4282A with different turn-on and turn-off character-  
istics to choose from, depending upon the specific  
requirements of an application. The first version, the  
AAT4282A-1, has a moderate turn-on slew rate feature,  
which reduces in-rush current when the MOSFET is  
turned on. This function 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 condition. 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  
The second version, the AAT4282A-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 final switch ver-  
sion, the AAT4282A-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. Using the  
FAST input pin on the AAT4282A-3, the device can be  
manually switched to a slower slew rate.  
All versions of the AAT4282A operate with input voltages  
ranging from 1.5V to 6.5V. All versions of this device  
have extremely low operating current, making them  
ideal for battery-powered applications.  
The ON/OFF control pin is TTL compatible and will also  
function with 2.5V to 5V logic systems, making the  
AAT4282A an ideal level-shifting load switch.  
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4282A.2008.02.1.2  
PRODUCT DATASHEET  
AAT4282A  
SmartSwitchTM  
Slew Rate Controlled Load Switch  
exceed VIN should be avoided since this would forward  
bias the internal parasitic diode and allow excessive cur-  
rent flow into the VOUT pin, possibly damaging 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.  
Applications Information  
Input Capacitor  
A 1F or larger capacitor is typically recommended for  
CIN in most applications. A CIN capacitor is not required  
for basic operation; however, it is useful in preventing  
load transients from affecting upstream circuits. CIN  
should be located as close to the device VIN pin as prac-  
tically possible. Ceramic, tantalum, or aluminum electro-  
lytic capacitors may be selected for CIN. There is no  
specific capacitor equivalent series resistance (ESR)  
requirement for CIN. However, for higher current opera-  
tion, ceramic capacitors are recommended for CIN due to  
their inherent capability over tantalum capacitors to  
withstand input current surges from low-impedance  
sources, such as batteries in portable devices.  
Thermal Considerations and  
High Output Current Applications  
The AAT4282A 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  
must be taken into account.  
Output Capacitor  
For proper slew operation, a 0.1F capacitor or greater  
is required between VOUT and GND. Likewise, with the  
output capacitor, there is no specific capacitor ESR  
requirement. If desired, COUT may be increased without  
limit to accommodate any load transient condition with-  
out adversely affecting the slew rate.  
The following discussions will assume the load switch is  
mounted on a printed circuit board utilizing the mini-  
mum recommended footprint as stated in the Printed  
Circuit Board Layout Recommendations section of this  
datasheet.  
Enable Function  
The AAT4282A features an enable / disable function. This  
pin (ON) is active high and is compatible with TTL or  
CMOS logic. To assure the load switch will turn on, the  
ON control level must be greater than 1.4V. The load  
switch will go into shutdown mode when the voltage on  
the ON pin falls below 0.4V. When the load switch is in  
shutdown mode, the OUT pin is tri-stated, and quiescent  
current drops to leakage levels below 1A.  
At any given ambient temperature (TA), the maximum  
package power dissipation can be determined by the fol-  
lowing equation:  
TJ(MAX) - TA  
PD(MAX)  
=
θJA  
Constants for the AAT4282A are maximum junction tem-  
perature (TJ(MAX) = 125°C)1 and package thermal resis-  
tance (θJA = 70°C/W). Worst case conditions are calcu-  
lated at the maximum operating temperature, TA =  
85°C. Typical conditions are calculated under normal  
ambient conditions where TA = 25°C. At TA = 85°C,  
PD(MAX) = 571mW. At TA = 25°C, PD(MAX) = 1429mW.  
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 parasitic diode. Conditions where VOUT might  
1. The actual maximum junction temperature of AAT4282A is 150°C. However, good design practice is to derate the maximum die temperature to 125°C to prevent the possibil-  
ity of over-temperature damage.  
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PRODUCT DATASHEET  
AAT4282A  
SmartSwitchTM  
Slew Rate Controlled Load Switch  
The maximum continuous output current for the  
AAT4282A 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, at 125°C:  
and has short 3A current peaks, as in a GSM application.  
The current peak occurs for 576s out of a 4.61ms period.  
First, the current duty cycle is calculated:  
x
576μs  
4.61ms  
% Peak Duty Cycle =  
=
100  
% Peak Duty Cycle = 12.5%  
RDS(MAX) = RDS(25°C) · (1 + TC · ΔT)Ω  
The load current is 100mA for 87.5% of the 4.61ms  
period and 3A for 12.5% of the period. Since the  
Electrical Characteristics do not report RDS(MAX) for 4V  
operation, it must be approximated by consulting the  
chart of RDS(ON) vs. VIN. The RDS reported for 5V at 100mA  
and 3A can be scaled by the ratio seen in the chart to  
derive the RDS for 4V VIN at 25°C: 130mΩ · 63mΩ/60mΩ  
= 136.5mΩ. De-rated for temperature: 136.5mΩ · (1 +  
0.002800 · (125°C - 25°C)) = 174.7mΩ.  
RDS(MAX) = 130mΩ · + 0.002800 · (125°C - 25°C))  
RDS(MAX) = 166.4mΩ  
For maximum current, refer to the following equation:  
PD(MAX)  
IOUT(MAX)  
<
RDS  
For example, if VIN = 5V, RDS(MAX) = 166.4mΩ, and TA =  
25°C, IOUT(MAX) = 2.93A. If the output load current were  
to exceed 2.93A 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 AAT4282A. To accomplish this,  
the device thermal resistance must be reduced by  
increasing the heat sink area or by operating the load  
switch in a duty cycle manner. Duty cycles with peaks  
less than 2ms in duration can be considered using the  
method described in the High Peak Current Applications  
section of this datasheet.  
For channel A, the power dissipation for a continuous 1A  
load is calculated as follows:  
PD(CHA) = IOUT2 · RDS = (1A)2 · 174.7mΩ = 174.7mW  
For channel B, the power dissipation for 100mA load is  
calculated as follows:  
PD(MAX) = IOUT2 · RDS  
PD(100mA) = (100mA)2 · 174.7mΩ  
PD(100mA) = 1.75mW  
PD(87.5%D/C) = %DC · PD(100mA)  
PD(87.5%D/C) = 0.875 · 1.75mW  
PD(87.5%D/C) = 1.53mW  
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. Refer to the IDM specification in the  
Absolute Maximum Ratings table to ensure the AAT4282A’s  
maximum pulsed current rating is not exceeded. The duty  
cycle for both output current levels must be taken into  
account. To do so, first calculate the power dissipation at  
the nominal continuous current level, and then add the  
additional power dissipation due to the short duration,  
high-current peak scaled by the duty factor. For example,  
a 4V system using an AAT4282A which has channel A  
operates at a continuous 1A load current level, and chan-  
nel B operates at a continuous 100mA load current level  
The power dissipation for 100mA load at 87.5% duty  
cycle is 1.53mW. Now the power dissipation for the  
remaining 12.5% of the duty cycle at 3A is calculated:  
PD(MAX) = IOUT2 · RDS  
PD(3A) = (3A)2 · 174.7mΩ  
PD(3A) = 1572mW  
PD(12.5%D/C) = %DC · PD(3A)  
PD(12.5%D/C) = 0.125 · 1572mW  
PD(12.5%D/C) = 196.7mW  
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10  
4282A.2008.02.1.2  
PRODUCT DATASHEET  
AAT4282A  
SmartSwitchTM  
Slew Rate Controlled Load Switch  
Finally, the total power dissipation for channels A and B  
is determined as follows:  
Printed Circuit Board  
Layout Recommendations  
For proper thermal management, and to take advantage  
of the low RDS(ON) of the AAT4282A, 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. For best performance,  
CIN and COUT should be placed close to the package pins.  
PD(total) = PD(CHA) + PD(100mA) + PD(3A)  
PD(total) = 174.7mW + 1.53mW + 196.7mW  
PD(total) = 373mW  
The maximum power dissipation for the AAT4282A oper-  
ating at an ambient temperature of 85°C is 373mW. The  
device in this example will have a total power dissipation  
of 571mW. This is well within the thermal limits for safe  
operation of the device; in fact, at 85°C, the AAT4282A  
will handle a 3A pulse for up to 25% duty cycle. At lower  
ambient temperatures, the duty cycle can be further  
increased.  
Evaluation Board Layout  
The AAT4282A evaluation layout follows the printed cir-  
cuit board layout recommendations and can be used for  
good applications layout. Refer to Figures 1 through 2.  
Note: Board layout shown is not to scale.  
Figure 1: Evaluation Board Top Side Layout.  
Figure 2: Evaluation Board Bottom Side Layout.  
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4282A.2008.02.1.2  
11  
PRODUCT DATASHEET  
AAT4282A  
SmartSwitchTM  
Slew Rate Controlled Load Switch  
Ordering Information  
Device Option  
Package  
Marking1  
Part Number (Tape and Reel)2  
AAT4282A-3  
FTDFN22-8  
WKXYY  
AAT4282AIPS-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 Information3  
FTDFN22-8  
0.400 ± 0.050  
Detail "A"  
Index Area  
Bottom View  
2.000 ± 0.050  
Top View  
0.500 ± 0.050  
+
0.100  
0.000  
- 0.000  
Side View  
Pin 1 Identification  
Detail "A"  
All dimensions in millimeters.  
1. XYY = assembly and date code.  
2. Sample stock is generally held on part numbers listed in BOLD.  
3. The leadless package family, which includes QFN, TQFN, DFN, FTDFN, TDFN and STDFN, has exposed copper (unplated) at the end of the lead terminals due to the manufactur-  
ing process. A solder fillet at the exposed copper edge cannot be guaranteed and is not required to ensure a proper bottom solder connection.  
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12  
4282A.2008.02.1.2  
PRODUCT DATASHEET  
AAT4282A  
SmartSwitchTM  
Slew Rate Controlled Load Switch  
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 specications 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 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. Specic 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.  
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4282A.2008.02.1.2  
13  

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