AAT3520/2/4
MicroPowerTM Microprocessor Reset CircuitPowerManagerTM
PRODUCT DATASHEET
3520.2010.03.1.4 1
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General Description
The AAT3520 series of PowerManager products is part of
AnalogicTech’s Total Power Management IC™ (TPMIC™)
product family. These microprocessor reset circuits are
ideal for monitoring voltage supplies in portable sys-
tems, where extended battery life is critical. They pro-
vide a low-cost, reliable solution by eliminating the need
for external components. The AAT3520 series operates
by monitoring the system power supply voltage. When
the input voltage drops below a fixed threshold, the
device asserts a reset signal for a fixed time period after
VCC has risen back above the fixed threshold; 30ms and
150ms minimum periods are available. The AAT3520
product series is guaranteed to operate down to 1.2V
and is designed to ignore fast line transients appearing
on VCC. The AAT3520 series is available with three out-
put stage versions: AAT3520 push-pull active high out-
put; AAT3522 push-pull active low output; and AAT3524
open drain active low output. The quiescent supply cur-
rent is extremely low, typically 1μA, making it ideal for
portable battery-operated equipment.
The AAT3520/2/4 are available in a Pb-free, 3-pin SOT23
package and are specified over the -40°C to +85°C
operating temperature range.
Features
• Input Voltage Range: 1.2V to 5.5V
• Operation Down to 1.2V
• Extremely Low Quiescent Current: <2μA
• High Accuracy Detection Threshold: ±1.5%
• Monitor Power Supply Voltages
• Fixed Thresholds from 2.2V to 4.6V
• -Reset Pulse Width Options
▪ Minimum 30ms or 150ms or 300ms
▪ Fast Propagation Delay <20μs
• Available Output Configurations:
▪ Open-Drain Output
▪ CMOS Active High Output
▪ CMOS Active Low Output
• Temperature Range: -40°C to +85°C
• 3-Pin SOT23 Package
• 4kV ESD Rating
Applications
• Cell Phones
• Embedded Systems
• Intelligent Instruments
• Notebook Computers
• Portable Electronics
Typical Application
*AAT3524 Only
AAT3520
AAT3522
AAT3524
µP
V
CC
VCCVCC
RESET
(RESET)
GNDGND
RESET
INPUT
100kΩ
(nominal)
*
AAT3520/2/4
MicroPowerTM Microprocessor Reset CircuitPowerManagerTM
PRODUCT DATASHEET
2 3520.2010.03.1.4
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Pin Descriptions
Pin # Symbol Function
1 GND Ground connection.
2
RESET
(AAT3520)
RESET output remains high while VCC is below the reset threshold and remains so for a fi xed time pe-
riod after VCC raises above the reset threshold.
RESET
(AAT3522,
AAT3524)
RESET output remains low while VCC is below the reset threshold and remains so for a fi xed time period
after VCC raises above the reset threshold.
3 VCC Supply voltage (+1.2V to +5.5V). Due to extremely low operating current, place a 10nF capacitor
between VCC and GND.
Part Number Descriptions
Part Number Part Description
AAT3520 Reset Output Push Pull Active High with Delay
AAT3522 Reset Output Push Pull Active Low with Delay
AAT3524 Reset Output Open Drain Active Low with Delay
Pin Configuration
SOT23-3
(Top View)
VCC
(RESET) RESET
GND
1
2
3
AAT3520/2/4
MicroPowerTM Microprocessor Reset CircuitPowerManagerTM
PRODUCT DATASHEET
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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. Mounted on an FR4 board.
Absolute Maximum Ratings1
TA = 25°C, unless otherwise noted.
Symbol Description Value Units
VCC VCC to GND -0.3 to 5.5 V
VRESET
RESET to GND (Push-Pull Output) -0.3 to VCC + 0.3 V
RESET to GND (Open Drain Output) -0.3 to 5.5
IMAX Maximum Continuous Input Current 20 mA
IRESET RESET/RESET Current 20 mA
dVCC/dtRate of Rise of VCC 100 V/μs
TJOperating Junction Temperature Range -40 to 150 °C
TLEAD Maximum Soldering Temperature (at Leads, 10 sec.) 300 °C
Thermal Information2
Symbol Description Value Units
ΘJA Maximum Thermal Resistance 200 °C/W
PDMaximum Power Dissipation 320 mW
AAT3520/2/4
MicroPowerTM Microprocessor Reset CircuitPowerManagerTM
PRODUCT DATASHEET
4 3520.2010.03.1.4
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Electrical Characteristics
VIN = 5V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = 25°C; VCC = 5V for 4.63/4.38V ver-
sions; VCC = 3.3V for 3.08/2.93V versions; VCC = 3.0V for 2.63V version; VCC = 2.5V for 2.32/2.2V versions.
Symbol Description Conditions Min Typ Max Units
VCC Operation Voltage TA = 0ºC to +70ºC 1.0 5.5 V
TA = -40ºC to +85ºC 1.2 5.5
IQQuiescent Current VCC = 5.5V 1.05 3 μA
VCC = 3V 0.85 2
VTH RESET Threshold (Table 1) TA = 25ºC VTH - 1.5% VTH VTH + 1.5% V
TA = -40ºC to +85ºC VTH - 2.5% VTH VTH + 2.5%
ΔVTH/°C RESET Threshold
Temperature Coeffi cient 40 ppm/°C
tPRESET Propagation Delay VCC = VTH to (VTH - 100mV) 15 μs
tRDY
RESET Active Timeout
Period
-50 Option 30 50 100
ms-200 Option 150 250 400
-400 Option 300 500 800
VOL
RESET Low Output Voltage
AAT3522, AAT3524
ISINK = 1.2mA, VCC = VTH(min), VTH ≤ 3.08V,
RESET Asserted 0.3
V
ISINK = 3.2mA, VCC = VTH(min), VTH > 3.08V,
RESET Asserted 0.4
VOH
RESET High Output Voltage
AAT3522
ISOURCE = 800μA, VTH > 3.08V, VCC > VTH (max) VCC -1.5 V
ISOURCE = 500μA, VTH ≤ 3.08V, VCC > VTH (max) 0.8 VCC
VOL
RESET Low Output Voltage
AAT3520
ISINK = 1.2mA, VCC > VTH (max), VTH ≤ 3.08V,
RESET Not Asserted 0.3
V
ISINK = 3.2mA, VCC > VTH (max), VTH > 3.08V,
RESET Not Asserted 0.4
VOH
RESET High Output Voltage
AAT3520
ISOURCE = 500μA, VCC > 2.1V, RESET Asserted 0.8VCC V
ISOURCE = 50μA, VCC > 1.2V, RESET Asserted 0.8VCC
IDOFF
RESET Leakage Current
AAT3524 VCC > VTH 1μA
AAT3520/2/4
MicroPowerTM Microprocessor Reset CircuitPowerManagerTM
PRODUCT DATASHEET
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Typical Characteristics
Supply Current vs. Temperature
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
-40 -20 0 20 40 60 80
Temperature (
°
C)
Supply Current (µA)
VCC = 5V
VCC = 3V
Normalized Reset Threshold
vs. Temperature
0.997
0.998
0.999
1.000
1.001
1.002
1.003
-40-200 20406080
Temperature (°C)
Normalized Threshold
Normalized Power-Up Reset Timeout
vs. Temperature
0.5
0.6
0.7
0.8
0.9
1
1.1
1.2
1.3
1.4
1.5
-40 -20 0 20 40 60 80 100
Temperature (°C)
Normalized Power-Up
Reset Timeout (ms)
Power-Down Reset Propagation
Delay vs. Temperature
0
5
10
15
20
25
30
-40 -20 0 20 40 60 80
Temperature (
°
C)
Reset Propagation Delay (µs)
VOD = 10mV
VOD = 100mV
Maximum Transient Duration
vs. Reset Threshold Overdrive
0
50
100
150
200
250
300
350
400
1 10 100 1000
Reset Threshold Overdrive, VTH - VCC (mV)
Maximum Transient
Duration (µs)
AAT3520/2/4
MicroPowerTM Microprocessor Reset CircuitPowerManagerTM
PRODUCT DATASHEET
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Functional Description
General
During start-up, the reset pin on a microprocessor
ensures that it is fully reset and starts up in a known
condition. The AAT3520 series of microprocessor reset
devices monitor the supply voltage to a microprocessor
and assert a reset signal whenever the VCC voltage falls
below a factory-programmed threshold. This threshold is
accurate within ±1.5% at 25ºC and within ±2.5% over
the entire operating temperature range. The reset signal
remains asserted for a fixed time period (tRDY) after VCC
has risen above the threshold, as shown in Figure 1. See
Ordering Information for available RESET active timeout
periods.
Functional Block Diagram
Reset
Generator
+ T imer
Oscillator
VCC
GND
RESET
(RESET)
VREF
V
RESET
CC
VTH VTH
VTH
tRDY tRDY
Figure 1: Reset Timing Diagram (AAT3522, AAT3524).
AAT3520/2/4
MicroPowerTM Microprocessor Reset CircuitPowerManagerTM
PRODUCT DATASHEET
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Applications Information
Reset Output Options
The AAT3524 has an active low open drain output and
the AAT3520/2 have a push-pull output. The AAT3524
may be used in multiple voltage systems with an exter-
nal pull-up resistor. This allows the AAT3524 to interface
to microprocessors with higher supply voltages up to
5.5V (Figure 3). In the event of a power down or brown-
out condition, the reset signal remains valid until the VCC
drops below 1.2V. To ensure validity down to ground, an
external 100kΩ resistor should be connected between
the RESET output and GND.
Supply Voltage Transient Behavior
In some cases, fast negative transients of short duration
can appear on the VCC power supply. The AAT3520 series
devices provide some immunity to line transients which
can generate invalid reset pulses. Figure 1 shows typical
behavior to short duration pulses versus RESET com-
parator overdrive. As shown in the Maximum Transient
Duration vs. Reset Threshold Overdrive graph, when the
transient voltage becomes larger, the time allowed
before asserting a reset becomes shorter (i.e., typically
a transient of 100mV below the reset threshold would
have to present for more than 50μs to cause a reset).
Immunity can be increased by the addition of a small
bypass capacitor of 0.1μF connected as closely to the VCC
pin as possible.
*AAT3524 Only
AAT3520
AAT3522
AAT3524
µP
V
0.1µF
CC
VCCVCC
RESET
(RESET)
GNDGND
RESET
INPUT
100kΩ
(nominal)
*
Figure 2: Using Recommended Bypass Capacitor.
AAT3520/2/4
MicroPowerTM Microprocessor Reset CircuitPowerManagerTM
PRODUCT DATASHEET
8 3520.2010.03.1.4
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AAT3524 5V
System
+3.3V
VCCVCC
RESET
100kΩ
GNDGND
RESET
INPUT
+5.0V
Figure 3: Using AAT3524 Open Drain Output with Multiple Supplies.
AAT3520/2/4
MicroPowerTM Microprocessor Reset CircuitPowerManagerTM
PRODUCT DATASHEET
3520.2010.03.1.4 9
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1. Contact Local Sales Office for custom trimmed options.
2. Sample stock is generally held on part numbers listed in BOLD.
3. XYY = assembly and date code.
Factory Trimmed Reset Thresholds1 and Ordering Information
Ordering
Part Number2Marking3
Minimum
Reset
Active (ms)
Reset Threshold Voltage, VTH (V)
TA = 25°C TA = -40°C to
+85°C
Min Typ Max Min Max
AAT3522IGY-2.20-200-T1 DBXYY 150 2.167 2.200 2.233 2.145 2.255
AAT3520IGY-2.32-200-T1
AAT3522IGY-2.32-200-T1
AAT3524IGY-2.32-200-T1
DTXYY
150
150
150
2.285 2.320 2.355 2.262 2.378
AAT3522IGY-2.45-200-T1 DXXYY 150 2.413 2.450 2.487 2.389 2.511
AAT3520IGY-2.63-200-T1
AAT3522IGY-2.63-200-T1
AAT3524IGY-2.63-200-T1
GNXYY
CAXYY
CWXYY
150
150
150
2.591 2.630 2.669 2.564 2.696
AAT3520IGY-2.93-200-T1
AAT3522IGY-2.93-50-T1
AAT3522IGY-2.93-200-T1
AAT3524IGY-2.93-200-T1
CZXYY
FVXYY
CCXYY
FPXYY
150
30
150
150
2.886 2.930 2.974 2.857 3.003
AAT3520IGY-3.08-50-T1
AAT3520IGY-3.08-200-T1
AAT3522IGY-3.08-50-T1
AAT3522IGY-3.08-200-T1
AAT3524IGY-3.08-200-T1
AAT3524IGY-3.08-400-T1
EFXYY
CNXYY
CYXYY
CBXYY
BGXYY
J7XYY
30
150
30
150
150
300
3.034 3.080 3.126 3.003 3.157
AAT3520IGY-4.38-200-T1
AAT3522IGY-4.38-200-T1
AAT3524IGY-4.38-200-T1
FUXYY
IVXYY
150
4.314 4.380 4.446 4.271 4.490150
150
AAT3520IGY-4.63-200-T1
AAT3522IGY-4.63-200-T1
AAT3524IGY-4.63-200-T1
HKXYY
DAXYY
DUXYY
150
4.561 4.630 4.699 4.514 4.746150
150
AAT3520/2/4
MicroPowerTM Microprocessor Reset CircuitPowerManagerTM
PRODUCT DATASHEET
10 3520.2010.03.1.4
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.
Package Information
SOT23-3
0.95 BSC
1.90 BSC
0.40
±
0.10
×
3
2.92
±
0.12
0.50
±
0.10 0.54 REF
1.30
±
0.10
2.37
±
0.27
0.075
±
0.075
0.96
±
0.21
0.86
±
0.16
0.14
±
0.06
4
°
±
4
°
All dimensions in millimeters.
