ANALOGICTECH AAT3128ITO-T1

PRODUCT DATASHEET
AAT3128
ChargePumpTM
RGB LED Fashion Lighting Controller
General Description
Features
The AAT3128 is a total solution controller for RGB LED
fashion lighting. A simplified control scheme greatly reduces design complexity and accelerates time to market.
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•
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•
•
•
•
The AAT3128 contains a high efficiency tri-mode charge
pump DC/DC converter with 1X, 1.5X and 2X modes for
color LED applications. Current source outputs drive two
individual RGB LEDs for color displays, fashion and mood
lighting. With a single-wire S2Cwire interface, an RGB
LED module is easily controlled to display four distinct
lighting mood effects.
Low external parts count (two 1μF flying capacitors and
two small bypass capacitors) and high conversion efficiency make the AAT3128 ideally suited for small battery-powered portable applications.
2.7V to 5.5V Input Voltage Range
Compatible with Common Anode RGB LEDs
Four S2Cwire Controlled Lighting Moods
0~60mA Programmable Current Source
Low Noise Constant Frequency Operation
No Inductors
Small Application Circuit
Regulated Output Current
Integrated LED Control Switches
Automatic Soft-Start
Less than 1μA Shutdown Current
Applications
•
•
•
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•
The AAT3128 has a thermal management system to protect the device in the event of an output short circuit
condition. Built-in soft-start circuitry prevents excessive
inrush current during start-up. A low current shutdown
feature disconnects the load from the input source and
reduces quiescent current to less than 1μA.
Color Backlighting for Monochrome LCD Displays
Color Display Lighting
Fashion Lighting RGB LEDs
Mobile Handsets
MP3 Players
PDAs
Smart Phones
The AAT3128 is available in a 14-pin TSOPJW package.
Typical Application
IN
ISRC2
ISRC1
C1+
CP
VBATTERY
CIN
1μF
COUT
1μF
AAT3128
C1C2+
EN/SET
EN/SET
RSET
RSET
38.3kΩ
3128.2008.02.1.1
GND
C1
1μF
R
C1
1μF
C2DR
DG
DB
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G
B
RGB
LED 1
R
G
B
RGB
LED 2
1
PRODUCT DATASHEET
AAT3128
ChargePumpTM
RGB LED Fashion Lighting Controller
Pin Descriptions
Pin #
Symbol
1
2
3
4
5
6
7
8
9
10
RSET
DG
DR
DB
GND
IN
C2C2+
C1C1+
11
CP
12
ISRC1
13
ISRC2
14
EN/SET
Function
Current Setting Resistor. Connect a resistor from RSET to GND to program the maximum LED current
Green LED On/Off Switch. DG turns on/off the green LED. Connect the green LED cathode to DG.
Red LED On/Off Switch. DR turns on/off the red LED. Connect the red LED cathode to DR.
Blue LED On/Off Switch. DB turns on/off the blue LED. Connect the blue LED cathode to DB.
Ground.
Power Input. Connect the input power voltage source to IN. Connect a 1μF ceramic capacitor from IN to GND.
Flying Capacitor 2 Negative Node. Connect a 1μF ceramic capacitor between C2+ and C2-.
Flying Capacitor 2 Positive Node. Connect a 1μF ceramic capacitor between C2+ and C2-.
Flying Capacitor 1 Negative Node. Connect a 1μF ceramic capacitor between C1+ and C1-.
Flying Capacitor 1 Positive Node. Connect a 1μF ceramic capacitor between C1+ and C1-.
Charge Pump Output. CP is the output voltage stage of the internal charge pump. Bypass CP to GND with a
1μF ceramic capacitor.
LED Current Source 1. ISRC1 controls the current through the LEDs connected to it. Connect the RGB LED
anode or LED array anodes to ISRC1.
LED Current Source 2. ISRC2 controls the current through the LEDs connected to it. Connect the RGB LED
anode or LED array anodes to ISRC2.
Enable/Set Input. ENSET turns on/off the AAT3128 and is the S2Cwire serial interface input to control the
LED color and brightness mood function. This node uses active high logic.
Pin Configuration
TSOPJW-14
(Top View)
RSET
DG
DR
DB
GND
IN
C2-
2
1
14
2
13
3
12
4
11
5
10
6
9
7
8
EN/SET
ISRC2
ISRC1
CP
C1+
C1C2+
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3128.2008.02.1.1
PRODUCT DATASHEET
AAT3128
ChargePumpTM
RGB LED Fashion Lighting Controller
Absolute Maximum Ratings1
Symbol
VIN, VCP
VC1+, VC1-, VC2+, VC2VEN/SET, VRSET, VISRC1,
VISRC2, VDG, VDR, VDB
TJ
TLEAD
Value
Units
IN, CP to GND
C1+, C1-, C2+, C2- to GND
Description
-0.3 to 6
-0.3 to VCP + 0.3
V
V
EN/SET, RSET, ISRC1, ISRC2, DG, DR, DB to GND
-0.3 to VIN + 0.3
V
-40 to 150
300
°C
°C
Value
Units
160
625
°C/W
mW
Operating Junction Temperature Range
Maximum Soldering Temperature (at leads, 10 sec)
Thermal Characteristics2
Symbol
θJA
PD
Description
Maximum Thermal Resistance
Maximum Power Dissipation
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 a FR4 board.
3128.2008.02.1.1
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3
PRODUCT DATASHEET
AAT3128
ChargePumpTM
RGB LED Fashion Lighting Controller
Electrical Characteristics
VIN = 3.6V, CIN = COUT = C1 = C2 = 1.0μF; TA = -40 to +85˚C. Unless otherwise noted, typical values are TA = 25˚C.
Symbol
Description
Input Power Supply
VIN
Input Operation Range
ICC
Operating Current
ISHDN
Shutdown Current
ISRC
Output Current Accuracy
η
Efficiency
Charge Pump
Soft-Start Time
TSS
FCLK
Clock Frequency
η
Efficiency
Switches
RDS(ON)
Switch On Resistance
EN/SET
VEN(L)
Enable Threshold Low
VEN(H)
Enable Threshold High
TEN/SET LO
EN/SET Low Time
TEN/SET HI
Minimum EN/SET High Time
TOFF
EN/SET Off Timeout
TLAT
EN/SET Latch Timeout
IEN/SET
EN/SET Input Leakage
Conditions
Min
Typ
Max
Units
5.5
7
10
5
93
V
mA
μA
%
%
200
1
93
μs
MHz
%
2
Ω
2.7
3.0 ≤
EN =
3.0 ≤
VIN =
VIN ≤ 5.5, CP = 1.5x, No Load Current
0
VIN ≤ 5.5
3.5
3
-5
VIN = 3.5
VIN = 3.5, TA = 25°C
0.4
VEN/SET
VEN/SET
VEN/SET
VEN/SET
VEN/SET
<
>
<
>
=
0.6V
1.4V
0.6V
1.4V
5V
1.4
0.3
75
50
-1
500
500
1
V
V
μs
ns
μs
μs
μA
1. The AAT3128 is guaranteed to meet performance specification over the –40 to +85°C operating temperature range, and are assured by design, characterization and correlation
with statistical process controls.
4
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3128.2008.02.1.1
PRODUCT DATASHEET
AAT3128
ChargePumpTM
RGB LED Fashion Lighting Controller
Typical Characteristics
Current Source Output vs. Input Voltage
Shutdown Current vs. Input Voltage
6.0
80
Shutdown Current (µA)
ISRC1 Current (mA)
90
-40°C
70
60
50
85°C
25°C
40
30
20
2.5
2.8
3.1
3.4
3.7
4.0
4.3
4.6
4.9
5.2
85°C
5.0
4.0
3.0
2.0
0.0
2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 5.3 5.5
5.5
Input Voltage (V)
Input Voltage (V)
Enable Input High Threshold
vs. Input Voltage
Enable Input Low Threshold
vs. Input Voltage
1.2
1.2
1.1
-40°C
1.0
1.0
0.9
0.9
VIL (V)
VIH (V)
1.1
0.8
0.7
25°C
0.6
85°C
0.8
0.7
2.7
3.0
3.3
3.6
3.9
4.2
4.5
4.8
5.1
0.4
2.7
5.4
3.6
3.9
4.2
4.5
4.8
5.1
5.4
400
350
350
-40°C
250
200
150
25°C
85°C
250
200
150
100
25°C
85°C
50
0
2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 5.3 5.5
Input Voltage (V)
3128.2008.02.1.1
-40°C
300
TLAT (µs)
TOFF (µs)
3.3
S2Cwire Latch Enable Time vs. Input Voltage
400
50
3.0
Input Voltage (V)
EN/SET Turn-Off Time vs. Input Voltage
100
85°C
25°C
0.5
Input Voltage (V)
300
-40°C
0.6
0.5
0.4
-40°C
25°C
1.0
0
2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 5.3 5.5
Input Voltage (V)
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5
PRODUCT DATASHEET
AAT3128
ChargePumpTM
RGB LED Fashion Lighting Controller
Typical Characteristics
Input vs. Output Transient
Input vs. Output Transient
(VIN = 2.7V; Data 1)
(VIN = 2.7V; Data 5)
VISRC1
(2V/div)
VISRC1
(2V/div)
VIN
(200mV/div)
VIN
(200mV/div)
IIN
(200mA/div)
IIN
(200mA/div)
Time (500µs/div)
Time (500µs/div)
Input vs. Output Transient
Input vs. Output Transient
(VIN = 3.6V; Data 1)
(VIN = 3.6V; Data 5)
VISRC1
(2V/div)
VISRC1
(2V/div)
VIN
(200mV/div)
VIN
(200mV/div)
IIN
(200mA/div)
IIN
(200mA/div)
Time (500µs/div)
Time (500µs/div)
Input vs. Output Transient
Input vs. Output Transient
(VIN = 4.2V; Data 1)
(VIN = 4.2V; Data 5)
VISRC1
(2V/div)
VISRC1
(2V/div)
VIN
(200mV/div)
VIN
(200mV/div)
IIN
(200mA/div)
IIN
(200mA/div)
Time (500µs/div)
6
Time (500µs/div)
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3128.2008.02.1.1
PRODUCT DATASHEET
AAT3128
ChargePumpTM
RGB LED Fashion Lighting Controller
Functional Block Diagram
Soft Start
C1+
1X
1.5X
2X
Charge
Pump
1MHz
Oscillator
Voltage
Reference
C1C2+
C2CP
RSET
ISRC1
Control
ISRC2
2
EN/SET
S Cwire
Interface
Current Level
Program
and LED
Switch / Mood
DR
DG
DB
Functional Description
The AAT3128 is specifically designed to drive RGB color
LEDs. This device is externally programmed via the simple single wire serial S2Cwire interface to set one of 16
color lighting modes based on four distinct preset color
light mood schemes. In addition to the four color lighting
moods, there are two brightness levels and two lightning
sequence change speeds that may be selected.
The AAT3128 utilizes a tri mode load switch (1X) and
high efficiency (1.5X or 2X) charge pump boost converter intended for RGB color LED lighting applications.
To maximize power conversion efficiency, an internal
sensing circuit monitors the voltage required for the constant current source outputs and sets the load switch or
charge pump modes based on the input battery voltage.
As the battery discharges over time, the AAT3128 charge
pump is enabled when the current source outputs near
dropout. The charge pump initially starts in 1.5X mode.
If the charge pump output droops enough for the current
source output to become close to dropout, the charge
3128.2008.02.1.1
pump will automatically transition to 2X mode. This load
switch to charge pump control system provides the
maximum power conversion efficiency for any given
operating condition.
The AAT3128 requires only four external components:
two 1μF ceramic capacitors for the charge pump flying
capacitors (C1 and C2), one 1μF ceramic input capacitor
(CIN) and one 1μF ceramic output capacitor (CP).
RGB LED Lighting Set-Up and Control
The AAT3128 has four preset RGB LED color lighting
moods which may be selected via the EN/SET function.
These four lighting color moods are outlined in Table 1.
Each lighting color mood mode selects a preset group of
64 unique colors that the system controller repeatedly
sequences through at a selected fast or slow rate.
RGB LED brightness and color change timing may be
varied by a choice of two levels for both. The Brightness
control permits the full current to power the RGB LED
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7
PRODUCT DATASHEET
AAT3128
ChargePumpTM
RGB LED Fashion Lighting Controller
based on the current set level programmed by the RSET
resistor. The second dimming level is fixed at 6dB below
that programmed by the RSET resistor. The pace of the
color change for a given mood light option can be set to
a fast or slow rate.
Through the S2Cwire interface, mood options allow the
user to select between four different moods, each with
two brightness levels and two speeds, based on the
number of rising edges of the EN/SET pin. 16 unique
moods are selected based on the settings in Table 2.
timeout period. After the TOFF time out time, all internal
registers are reset and the charge pump is disabled.
It is advisable to issue a 500μs low pulse to reset the data
registers before send new sets of data to change lighting
modes. This will avoid any possibility of losing synchronization between the AAT3128 and the system MCU.
Mood
Name
Color Description
M1
Rainbow 1
M2
Electric Beat
EN/SET Serial Interface
M3
Rainbow 2
The lighting mood output is controlled by the EN/SET
pin, using AnalogicTech’s Simple Serial Control™
(S2Cwire) interface. The interface records rising edges of
the EN/SET pin, and decodes them into 16 individual settings based on an internal preset ROM table. The interface counter can be clocked at speeds up to 1MHz. The
rising edges of EN/SET input enable the IC and are
counted for 1 to 16 edges based on the desired mode.
Once the final clock cycle is input for the desired mode
the EN/SET pin is held high to enable the device output.
The device is disabled 500μs after the EN/SET pin transitions to a logic low state.
M4
Firelight
Full color wheel control with continuous smooth transitions
Pulsing Blue – White – Red color tones
Full color wheel control with varied
timing for transitions
Red-Orange-Yellow flickering light
Table 1: Programmable RGB LED
Color Lighting “Moods.”
The EN/SET timing is designed to accommodate a wide
range of data rates. After the first rising edge of EN/SET,
the charge pump is enabled and reaches full capacity after
the soft-start time (TSS). During the soft start time, multiple clock pulses may be entered on the EN/SET pin to set
the final output current level with a single burst of clocks.
A constant current is sourced and the programmed color
mood is enabled as long as EN/SET remains in a logic high
state. The current source outputs are switched off after
EN/SET has remained in a low state for at least the TOFF
Data
Bright/Dim
Fast/Slow
Mood
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
B
B
B
B
B
B
B
B
D
D
D
D
D
D
D
D
F
F
F
F
S
S
S
S
F
F
F
F
S
S
S
S
M1
M2
M3
M4
M1
M2
M3
M4
M1
M2
M3
M4
M1
M2
M3
M4
Table 2: AAT3128 S2Cwire Programming Modes.
EN/SET Timing
tLO
tHI
tOFF
EN/SET
Code
OFF
1
2
3
OFF
Figure 1: S2Cwire Timing Diagram.
8
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3128.2008.02.1.1
PRODUCT DATASHEET
AAT3128
RGB LED Fashion Lighting Controller
Application Information
RSET Selection
The maximum output current for current sources ISRC1
and ISRC2 is programmed by the RSET resistor. A nominal value of 38.3kΩ will set each current source output
to 60mA each. Lower maximum current levels may be
programmed by reducing the value of RSET. Refer to
Table 3 for RSET resistor values to set the maximum
brightness constant current rounded off to the closest
1% value.
Current Source Output (mA)
RSET Value (kΩ)
60
50
40
30
20
10
38.3
46.6
57.6
76.8
115
232
Table 3: RSET Programming Values.
If a desired current source output level is not listed in
Table 3, the RSET resistor value may be calculated using
the following formula:
RSET =
(1920 · VREF)
IOUT
Where:
VREF = 1.2V
IOUT = Desired output current for ISRC1 and ISRC2
(ISRC1 = ISRC2 ≤ 60mA)
RGB LED Selection
The AAT3128 is specifically intended for driving RGB
color LEDs. However, the device design will allow the
AAT3128 to drive most types of LEDs with forward voltage specifications ranging from 1.0V to 5.0V. The two
current sink outputs provide up to 60mA each and may
be paralleled to drive high-current LEDs up to 120mA
without complication.
Most RGB color LEDs have greatly varied forward voltage
specifications for each red, green and blue LED for a
given forward current operating condition. Refer to
Figure 2 or the datasheet for a given RGB LED to be used
3128.2008.02.1.1
with the AAT3128. Since the ISRC1 and ISRC2 output
current sources are matched with negligible voltage
dependence, RGB LED brightness and color will be
matched regardless of specific LED forward voltage (VF)
variations.
0.08
Forward Current (IF) (A)
ChargePumpTM
0.07
0.06
0.05
0.04
0.03
0.02
0.01
0.00
1.00
1.50
2.00
2.50
3.00
3.50
4.00
Forward Voltage (VF ) (V)
Figure 2: Typical RGB LED Forward Voltage vs.
Forward Current Characteristics.
Capacitor Selection
Careful selection of the four external capacitors CIN, C1,
C2, and COUT is important because they will affect turnon time, output ripple, and transient performance.
Optimum performance will be obtained when low equivalent series resistance (ESR) ceramic capacitors are
used. In general, low ESR may be defined as less than
50mΩ. For best overall performance, 1μF capacitors are
recommended.
Depending on ripple requirements, the input and output
capacitor values can be increased or decreased accordingly. If lower ripple is desired, increase the capacitor
value. The peak-to-peak ripple seen at the input or output increases or decreases with capacitor size.
Capacitor Characteristics
Ceramic composition capacitors are highly recommended over all other types of capacitors for use with the
AAT3128. Ceramic capacitors offer many advantages
over their tantalum and aluminum electrolytic counterparts. A ceramic capacitor typically has very low ESR, is
lowest cost, has a smaller PCB footprint, and is nonpolarized. Low ESR ceramic capacitors help maximize
charge pump transient response. Since ceramic capacitors are non-polarized, they are not prone to incorrect
connection damage.
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9
PRODUCT DATASHEET
AAT3128
ChargePumpTM
RGB LED Fashion Lighting Controller
Equivalent Series Resistance
ESR is an important characteristic to consider when
selecting a capacitor. ESR is a resistance internal to a
capacitor that is caused by the leads, internal connections, size or area, material composition, and ambient
temperature. Capacitor ESR is typically measured in milliohms for ceramic capacitors and can range to more
than several ohms for tantalum or aluminum electrolytic
capacitors.
Ceramic Capacitor Materials
Capacitors used in AAT3128 applications range in value
from 0.47μF to 2.2μF. Nominally a 1μF capacitor with a
minimum voltage specification exceeding 6V is recommended. Ceramic capacitors in this range are typically
composed of X7R, X5R, Z5U, or Y5V dielectric materials.
The use of X5R and X7R dielectric capacitors is strongly
recommended due to their inherent low ESR characteristics and improved tolerance specifications over the
device operating temperature range.
Capacitors that are physically larger will have a lower
ESR when compared to a smaller case size capacitor
made from an equivalent material. These larger devices
can improve circuit transient response when compared
to an equal value capacitor in a smaller package size.
Layout Considerations
The AAT3128 is a high-performance device that operates
with a high switching frequency. To ensure optimal device
performance and accommodate the fast switched capacitor transients generated by the AAT3128, special attention should be given to the printed circuit board (PCB)
layout. The PCB traces connecting C1 and C2 experience
fast current transients. As a result, the trace lengths for
C1 and C2 should be minimized by placing the components as closely as possible to the IC. This will minimize
path resistance and reduce ringing due to the inductance
associated with trace length. For best IC performance, CIN
and COUT are placed as closely as possible to the IN and
CP pins and are connected to a solid ground.
AAT3128 Evaluation Board Layout
Figure 3: AAT3128 Evaluation Board
Component Side PCB Layout.
10
Figure 4: AAT3128 Evaluation Board
Solder Side PCB Layout.
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3128.2008.02.1.1
PRODUCT DATASHEET
AAT3128
ChargePumpTM
RGB LED Fashion Lighting Controller
AAT3128 Evaluation Board Schematic
RGB2
RGB1
B
G
R
B
G
JPx
DC-
DC+
1
VIN
2
3
J1
GND
R
JPx
JP1
R1
GND
38.3k
1
2
3
4
5
6
7
C3
1μF
RSET
DG
DR
DB
GND
IN
C2U1
EN/SET
ISRC2
ISRC1
CP
C1+
C1 C2+
14
13
12
11
10
9
8
C1
1μF
C2
1μF
AAT3128
C4
1μF
GND
GND
R7
100K
J2
VIN
GND
R4
1k
Cycle
R3
1k
R2
1k
SW3
Up
SW2
Down
SW1
1
2
3
4
VDD
GP5
GP4
GP3
U2
VSS
GP0
GP1
GP2
PIC12F675
C5
1μF
8
7
6
5
R6
1k
LED1
GRN
VR1 (opt)
POT10K
R5
1k
LED2
RED
GND
GND
GND
3128.2008.02.1.1
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PRODUCT DATASHEET
AAT3128
ChargePumpTM
RGB LED Fashion Lighting Controller
Ordering Information
Package
Marking1
Part Number (Tape and Reel)2
TSOPJW-14
VMXYY
AAT3128ITO-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
TSOPJW-14
2.85 ± 0.20
2.40 ± 0.10
0.20 +- 0.10
0.05
0.40 BSC
Top View
0.04 REF
0.05 +- 0.05
0.04
0.15 ± 0.05
+ 0.05
1.05 - 0.00
+ 0.000
1.00 - 0.075
3.05 +- 0.05
0.10
4° ± 4°
Side View
0.45 ± 0.15
2.75 ± 0.25
End View
All dimensions in millimeters.
1. XYY = assembly and date code.
2. Sample stock is generally held on part numbers listed in BOLD.
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 specifications 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 fitness 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. Specific 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.
12
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3128.2008.02.1.1