Analogic AAT1265 Low voltage 2mhz step-up dc/dc converter in sc70jw package Datasheet

PRODUCT DATASHEET
AAT1265
SwitchRegTM
Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package
General Description
Features
The AAT1265 is designed for single-cell or dual-cell alkaline, NiMH, or NiCd or single-cell lithium-ion/polymer
(Li-Ion) battery-powered applications. It is a high efficiency, synchronous, fixed frequency, step-up converter
with true output disconnect during shutdown (<1.0μA),
start-up inrush current limit, and short-circuit protection.
•
•
•
•
•
•
•
•
The high 2MHz switching frequency and completely integrated control circuitry minimize the total solution footprint area while maintaining excellent regulation, ripple,
and transient response throughout the full load range.
Light load switching frequency modulation and low quiescent current maintain high efficiency performance for
light load and sleep mode conditions.
With a 1A peak switch current limit, the AAT1265 is
capable of delivering 100mA to the load with a single AA
cell, up to 250mA from a dual AA cell, or up to 400mA
from a single-cell lithium-ion battery. The device has a
1.0V start-up voltage with operation down to 0.8V.
The AAT1265 is available in a Pb-free, space-saving
2.0x2.1mm 8-pin SC70JW package and is rated over the
-40°C to +85°C temperature range.
•
•
•
•
•
•
•
•
•
•
100mA Output from a Single AA Cell Input
250mA Output from a Dual AA Cell Input
400mA Output from a Single Lithium-Ion Cell Input
VIN Operation Range: 0.8V to VOUT
Up to 93% Efficiency
Low Start-Up Voltage: 1.0V Typical
Internal Synchronous Rectifier
Current Mode Control with Internal Feedback and
Compensation
2MHz Fixed Switching Frequency
1A Current Limit
Maintains High Efficiency Over the Output Current
Range for Improved Battery Life
Low 40μA No Load Bias Current
True Load Disconnect
Short-Circuit and Over-Current Protection
Inrush Current Limit and Soft Start
Low Shutdown Current: <1.0μA
-40°C to +85°C Temperature Range
2.0x2.1mm SC70JW-8 Package
Applications
•
•
•
•
•
Bluetooth® Headsets
Digital Cameras
Medical Instruments
Mobile Handsets
MP3 and Portable Music Players
Typical Application
VIN
VOUT
Dual-Cell to 3.3V Efficiency
vs. Output Current
AAT1265
LX
VCC
VIN
OUT
100
VIN = 3.0V
90
4.7μF
4.7μF
Efficiency (%)
2.2μH
80
VIN = 2.4V
VIN = 2.0V
70
60
EN
GND
50
0.1
1.0
10.0
100.0
1000.0
Output Current (mA)
1265.2007.12.1.4
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1
PRODUCT DATASHEET
AAT1265
SwitchRegTM
Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package
Pin Descriptions
Pin #
Symbol
1
VCC
2
EN
3
VIN
4
LX
5
OUT
6, 7, 8
GND
Function
Bias supply voltage after start-up and feedback to the output voltage error amplifier.
Enable pin. Logic high enables the IC. Logic low disables the IC and disconnects the load from the input.
Shutdown current is <1μA.
Battery input voltage. Supplies the IC at start-up.
Inductor connection. Ties to the drains of the P-channel synchronous rectifier and the N-channel MOSFET
switch.
Boost converter output voltage; connects to the P-channel synchronous MOSFET source. Bypass with
ceramic capacitor to GND.
Signal and power ground. Connect output capacitor return.
Pin Configuration
SC70JW-8
(Top View)
2
VCC
1
8
GND
EN
2
7
GND
VIN
3
6
GND
LX
4
5
OUT
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1265.2007.12.1.4
PRODUCT DATASHEET
AAT1265
SwitchRegTM
Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package
Absolute Maximum Ratings
Symbol
VN
TJ
TLEAD
Description
VIN, OUT, VCC, EN, LX to GND
Operating Junction Temperature Range
Maximum Soldering Temperature (at leads, 10 sec)
Value
Units
-0.3 to 6.0
-40 to 150
300
V
°C
°C
Value
Units
160
625
°C/W
mW
Thermal Characteristics1
Symbol
θJA
PD
Description
Maximum Thermal Resistance
Maximum Power Dissipation
1. Mounted on an FR4 board.
1265.2007.12.1.4
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3
PRODUCT DATASHEET
AAT1265
SwitchRegTM
Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package
Electrical Characteristics1
VIN = 1.2V, TA = -40°C to +85°C, unless otherwise noted. Typical values are TA = 25°C.
Symbol
Description
Conditions
VIN
Minimum Start-Up Voltage
Operating Input Voltage Range
ILOAD = 1mA
VOUT
Output Voltage Accuracy
IQ
ISHDN
RDS(ON)H
RDS(ON)L
ILIMIT
IPFM
η
ΔVOUT/
VOUT
ΔVOUT/
VOUT/ΔVIN
FOSC
DTYMAX
VTH(L-IN)
VTH(H-IN)
Quiescent Supply Current (Light Load
Operation)2
Shutdown Current
PMOS On-Resistance
NMOS On-Resistance
NMOS Current Limit
PFM Light Load Current Threshold
Efficiency
Load Regulation
Line Regulation
Switching Frequency
Maximum Duty Cycle
Logic Input Low Threshold for EN
Logic Input High Threshold for EN
Min
Typ
Max
1.0
Units
V
0.8
VOUT - 0.1
VOUT
VOUT + 0.1
VOUT - 0.15
VOUT + 0.15
V
70
μA
1.0
IOUT = 50mA, L = 2.2μH
750
400
1.0
20
82
μA
mΩ
mΩ
A
mA
%
ILOAD = 0 to 100mA
1.5
%
VIN = 0.8V to 2.5V
VIN = 2.5V to 4.2V; 5.0V Version
Only
TA = 25°C
0.2
VIN = 0.8V to 2.5V, PWM Mode
VIN = 2.5V to 4.2V, PWM Mode;
5.0V Version Only
No Load
40
EN = 0V, VIN = 5.5V
TA = 25°C
TA = 25°C
%/V
0.16
1.8
2.0
90
2.2
0.4
1.0
V
MHz
%
V
V
1. The AAT1265 is guaranteed to meet performance specifications over the -40°C to +85°C operating temperature range and is assured by design, characterization, and correlation with statistical process controls.
2. IQ = IQ_VOUT + IQ_VCC.
4
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1265.2007.12.1.4
PRODUCT DATASHEET
AAT1265
SwitchRegTM
Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package
Typical Characteristics
Single-Cell to 3.3V Efficiency
Dual-Cell to 3.3V Efficiency
100
100
VIN = 3.0V
90
VIN = 1.5V
Efficiency (%)
Efficiency (%)
90
80
70
VIN = 1.2V
80
VIN = 2.4V
70
60
60
50
50
0.1
1
10
100
0.1
1000
1
Output Current (mA)
10
100
Single-Cell Load Regulation
Dual-Cell Load Regulation
(VOUT = 3.3V)
(VOUT = 3.3V)
2.0
2.0
1.5
1.5
1.0
1.0
0.5
0.0
VIN = 1.5V
-0.5
-1.0
-1.5
0.1
1
0.5
VIN = 3.0V
0.0
VIN = 2.4V
-0.5
-1.0
-1.5
VIN = 1.2V
-2.0
1000
Output Current (mA)
VOUT Error (%)
VOUT Error (%)
VIN = 2.0V
VIN = 2.0V
-2.0
10
0.1
100
1
Output Current (mA)
10
100
1000
Output Current (mA)
Li-Ion/Polymer to 5V Efficiency
Li-Ion/Polymer Load Regulation
(VOUT = 5V)
2
100
VIN = 3.6V
80
VOUT Error (%)
Efficiency (%)
VIN = 3.1V
60
VIN = 3.6V
40
0
VIN = 4.2V
VIN = 3.1V
1.0
10.0
-2
VIN = 4.2V
20
0.1
1
10
100
1000
0.1
1265.2007.12.1.4
100.0
1000.0
Output Current (mA)
Output Current (mA)
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PRODUCT DATASHEET
AAT1265
SwitchRegTM
Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package
Typical Characteristics
3.3V to 5V Efficiency
3.3V to 5V Load Regulation
2
Output Error (%)
Efficiency (%)
100
80
60
40
20
0.1
1
10
100
0
-2
-4
0.1
1000
1
Output Current (mA)
Minimum Start-Up Voltage vs. Load Current
1000
120
2.4
Output Current (mA)
2.2
Constant Current Load
2.0
1.8
1.6
1.4
Resistive Load
1.2
1.0
100
Increasing Load
80
60
40
Decreasing Load
20
0
0.8
0
2
40
60
80
100
120
140
1.0
160
1.2
1.4
1.6
Current (mA)
1.8
2.0
2.2
2.4
2.6
2.8
3.0
Input Voltage (V)
No Load Input Current vs. Input Voltage
No Load Input Current vs. Input Voltage
(VOUT = 3.3V)
(VOUT = 5V)
350
Input Current (µA)
200
Input Current (µA)
100
Light Load Mode Output Current Threshold
vs. Input Voltage
(VOUT = 3.3V)
Voltage (V)
10
Output Current (mA)
160
120
80
40
300
250
200
150
100
50
0
0
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
2.6
2.8
3.0
6
1.8
2.2
2.6
3.0
3.4
3.8
4.2
4.6
Input Voltage (mA)
Input Voltage (V)
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1265.2007.12.1.4
PRODUCT DATASHEET
AAT1265
SwitchRegTM
Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package
Typical Characteristics
Maximum Load Current Capacity for a 4%
Drop in Output Voltage vs. Input Voltage
(VOUT = 3.3V)
0.5
600
0.0
Load Current (mA)
Switching Frequency Change (%)
Switching Frequency vs. Temperature
-0.5
-1.0
-1.5
-2.0
500
400
300
200
100
0
-2.5
-40
-15
10
35
60
1.0
85
1.2
1.4
1.6
Temperature (°°C)
1.8
2.0
2.2
2.4
2.6
2.8
3.0
Input Voltage (V)
Maximum Load Current Capability for a
4% Drop in Output Voltage vs. Input Voltage
Load Transient Response
(VIN = 1.2V; L = 2.2µH; CO = 4.7µF)
700
3.35
Output Current (A)
3.40
600
500
400
300
200
100
1.8
3.30
3.25
3.20
0.15
0.10
100mA
0.05
50mA
0.00
2.2
2.6
3.0
3.4
3.8
4.2
4.6
Time (50µs/div)
Input Voltage (V)
Output Voltage vs. Temperature
Line Transient Response
(VIN = 1.5V; IOUT = 10mA; VOUT = 3.3V)
(IOUT = 50mA; L = 2.2µH; COUT = 4.7µF)
2.50
2.4V
Output Voltage (V)
0.20
0.00
-0.20
-0.40
-0.60
-20
0
20
40
60
80
2.00
1.9V
3.34
1.75
1.50
3.32
3.30
3.28
3.26
Time (50µs/div)
Temperature (°°C)
1265.2007.12.1.4
2.25
Input Voltage (V)
Output Voltage Error (%)
0.40
-0.80
-40
Output Voltage (V)
Load Current (mA)
(VOUT = 5V)
800
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PRODUCT DATASHEET
AAT1265
SwitchRegTM
Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package
Soft-Start Inrush Current
(VIN = 2.4V; IOUT = 100mA; VOUT = 3.3V)
4
3
1.75
Output Voltage
1.5
1.25
1
1
Enable
0
-1
-2
0.75
0.5
Input Current
0.25
-3
0
-4
-0.25
3
Output Voltage
1.5
1.25
2
1
1
Enable
0
0.75
-1
0.5
-2
0.25
-3
Input Current
0
-0.25
-4
Time (500µs/div)
Time (500µs/div)
Full Load Output Ripple
Light Load Output Ripple
(VIN = 1.2V; IOUT = 10mA; VOUT = 3.3V)
(VIN = 1.2V; IOUT = 100mA; VOUT = 3.3V)
VOUT
(AC Coupled)
(20mV/div)
VOUT
(AC Coupled)
(20mV/div)
IL
(100mA/div)
IL
(200mA/div)
VLX
(2V/div)
VLX
(2V/div)
Time (250ns/div)
8
1.75
4
Input Current (A)
2
Enable and Output Voltage (V)
Soft-Start Inrush Current
(VIN = 1.2V; IOUT = 40mA; VOUT = 3.3V)
Input Current (A)
Enable and Output Voltage (V)
Typical Characteristics
Time (1µs/div)
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1265.2007.12.1.4
PRODUCT DATASHEET
AAT1265
SwitchRegTM
Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package
Functional Block Diagram
VCC
VIN
Start-Up
Inrush Control
OUT
Low Voltage
Start-Up
VREF
Voltage
Reference
DH
Mode
Control
2MHz
Oscillator
Current
Sense
LX
Logic
Comp.
DL
Error
Amp.
EN
GND
Functional Description
The AAT1265 synchronous step-up converter is targeted
for single- or dual-cell alkaline, NiMH, and NiCd and
single-cell lithium-ion/polymer battery applications. It
has a 1V typical start-up voltage with operation after
start-up to less than 0.8V.
The high 2MHz switching frequency of the AAT1265
facilitates output filter component size reduction for
improved power density and reduced overall footprint. It
also provides greater bandwidth and improved transient
response over other lower frequency step-up converters.
The compensation and feedback is integrated with only
three external components (CIN, COUT, L).
1265.2007.12.1.4
GND
Low RDS(ON) synchronous power switches provide high
efficiency for heavy load conditions. Switching frequency
modulation and low quiescent current maintains this
high efficiency for light load and sleep mode conditions.
In addition to the improved efficiency, the synchronous
boost has the added performance advantage of true load
disconnect during shutdown (<1μA shutdown current),
inrush current limit, and short-circuit protection.
PWM / Light Load Control
The AAT1265 is a fixed frequency PWM peak current mode
control step-up converter. For light load conditions (10 to
20mA and below), the converter transitions to a variable
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PRODUCT DATASHEET
AAT1265
SwitchRegTM
Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package
frequency (Light Load) mode to reduce the dominant
switching losses. In addition to Light Load operation, a
zero current comparator blocks reverse current in the
P-channel synchronous MOSFET, forcing DCM operation at
light load. These controls, along with very low quiescent
current, help to maintain high efficiency over the complete load range without the compromise of increased
output voltage ripple during light load conditions.
Start-up and Inrush Current Limit
The start-up sequence of the AAT1265 varies depending
upon whether the input voltage is greater than or less
than 2V. Above 1V, a start-up oscillator operating at
25% duty cycle controls the synchronous power stage
and charges the output to 2V. For an input voltage
greater than 2V, the output is charged at a constant current of 300mA until the output reaches a voltage level
just below the input voltage. The step-up converter then
takes control and continues to charge the output to the
steady-state voltage. The step-up converter N-channel
switch current is limited to 1A and the typical start-up
time is 2.5ms.
Shutdown and Output Disconnect
A typical synchronous step-up (boost) converter has a
conduction path from the input to the output via the
body diode of the P-channel MOSFET. The AAT1265
design disconnects this body diode from the output and
eliminates this conduction path. This enables the
AAT1265 to provide true load disconnect during shutdown and inrush current limit at turn-on.
Short-Circuit Protection
The P-channel synchronous MOSFET body diode disconnect feature also gives the AAT1265 the ability to provide output short-circuit current limit protection.
10
Applications Information
Inductor Selection
The AAT1265 is designed to operate with a 2.2μH inductor for all input/output voltage combinations. The inductor saturation current rating should be greater than the
NMOS current limit specification listed in the Electrical
Characteristics table. If necessary, the peak inductor current can exceed the saturation level by a small amount
with no significant effect on performance. Table 1 provides a list of some suggested inductor manufacturers
and their part numbers.
Output and Input Capacitor Selection
Surface mount X5R or X7R ceramic capacitors are suggested for both the output and the input. For the output
capacitor (C1 in Figure 4) a 4.7μF, 10V, X5R ceramic
capacitor is necessary for stability, transient response,
and ripple performance. The same 0805 sized capacitor
is used for the input (C2 of Figure 4). If desired, a
smaller, 0603 sized, 4.7μF, 6.3V, X5R ceramic capacitor
can be substituted for the input capacitor (C2). Suggested
ceramic capacitor suppliers are listed in Table 1.
PCB Layout Guidelines
Figures 1, 2, and 3 display the evaluation board layout
and suggested component placement. Due to the high
switching speed of the AAT1265, it is important that the
evaluation board layout be followed. Even the best
switch-mode power supply design cannot overcome the
problems that can be caused by a poor layout.
For the AAT1265, it is necessary that C1 and C2 be
placed as close as possible to the IC with a good low
impedance path to the GND pins of the IC. It is also
good practice to minimize the length of the trace from
the OUT pin to the output inductor. This prevents switching noise from radiating into other high noise sensitive,
high impedance circuits.
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1265.2007.12.1.4
PRODUCT DATASHEET
AAT1265
SwitchRegTM
Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package
Figure 1: AAT1265 Evaluation Board
Top Side.
Figure 2: Component Placement.
Figure 3: AAT1265 Evaluation Board
Bottom Side.
1265.2007.12.1.4
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PRODUCT DATASHEET
AAT1265
SwitchRegTM
Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package
VIN
U1
AAT1265
1
1
2
3
2
3
Enable
4
L1
2.2μH
VCC GND
EN
GND
VIN
GND
LX
OUT
8
7
6
VOUT
5
C1
4.7μF
C2
4.7μF
U1 AAT1265 SC70JW-8
L1 SD3118-2R2
C1, C2 4.7μF 10V 0805 X5R
Figure 4: AAT1265 Evaluation Board Schematic.
Manufacturer
Value
Part
Voltage
Case Size
Part Number
10V
6.3V
10V
6.3V
10V
6.3V
0805
0603
0805
0603
0805
0603
GRM21BR61A475KA73L
GRM188R60J475KE19D
C2012X5R1A475K
C1608X5ROJ475K
LMK212BJ475MG
JMK107BJ475MA
ISAT
DCR
Case Size
Part Number
Inductor
1.50A
75mΩ
3.2 x 3.2 x 1.55
CDRH2D14-2R2
Inductor
1.62A
69mΩ
3.1 x 3.1 x 1.85
SD3118-2R2
Output or Input Capacitor
Input Capacitor
Output or Input Capacitor
Input Capacitor
Output or Input Capacitor
Input Capacitor
Murata
www.murata.com
4.7μF
TDK
www.tdk.com
4.7μF
Taiyo Yuden
www.t-yuden.com
4.7μF
Manufacturer
Value
Part
2.2μH
2.2μH
Sumida
www.sumida.com
Cooper Electronics
www.cooperet.com
Table 1: Suggested Component Selection.
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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1265.2007.12.1.4
PRODUCT DATASHEET
AAT1265
SwitchRegTM
Low Voltage 2MHz Step-Up DC/DC Converter in SC70JW Package
Ordering Information
Voltage
Package
Marking1
Part Number (Tape and Reel)2
3.0V
3.3V
3.6V
5.0V
SC70JW-8
SC70JW-8
SC70JW-8
SC70JW-8
TCXYY
RLXYY
TBXYY
UQXYY
AAT1265IJS-3.0-T1
AAT1265IJS-3.3-T1
AAT1265IJS-3.6-T1
AAT1265IJS-5.0-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/pbfree.
Package Information
SC70JW-8
2.20 ± 0.20
1.75 ± 0.10
0.50 BSC 0.50 BSC 0.50 BSC
0.225 ± 0.075
2.00 ± 0.20
0.100
7° ± 3°
0.45 ± 0.10
4° ± 4°
0.05 ± 0.05
0.15 ± 0.05
1.10 MAX
0.85 ± 0.15
0.048REF
2.10 ± 0.30
All dimensions in millimeters.
z
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.
1265.2007.12.1.4
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