AATI_AN_41.pdf

EVALUATION BOARD DATASHEET
EV-146
AAT1265 EVAL: Low Voltage 2MHz Step-Up DC/DC Converter
Introduction
The AAT1265 evaluation board provides a platform for the testing and evaluation of the AAT1265 low voltage 2MHz
step-up regulator. The evaluation board demonstrates suggested size and placement of external components to maintain output voltage regulation for up to 250mA of output current. The external components are selected for small size
to suit portable applications while the layout has been optimized to achieve high efficiency with the SC70JW-8 package.
The design operates across an input voltage range of 0.8V to VOUT. The AAT1265 EVAL demo board provides a 3.3V
output at 250mA maximum output current for a dual AA cell input. This document provides details on the operation
and testing of the AAT1265 evaluation board.
Operating Specification
Specification
Input Voltage
Output Voltage Accuracy
Line Regulation
Load Regulation
Description/Conditions
Min
VIN = 0.8V to 2.5V, PWM Mode; TA = -40°C to +85°C
0.8V ≤ VIN ≤ 2.5V [ΔVOUT / VOUT / ΔVIN]
0mA ≤ IOUT ≤ 100mA [ΔVOUT / VOUT]
Typ
0.8
VOUT – 0.1V
0.2
1.5
Max
Units
VOUT
VOUT + 0.1V
V
%/V
%
Table 1: AAT1265 Evaluation Board Operating Specification.
Schematic
U1 AAT1265
L1
VIN
4
3
LX
VCC
VIN
OUT
1
5
VOUT
C2
C1
[CIN ]
[C OUT]
2
EN
GND
6,7,8
EN
Figure 1: AAT1265 Evaluation Board Schematic.
Bill of Materials (BOM)
Component
Part Number
U1
AAT1265IJS
C1608X5R1A475K
LMK107BJ475K
C2012X5R1A475K
GRM21BR61A475K
LMK212BJ475MG
PRPN401PAEN
SD3118-2R2
CDRH2D14-2R2
C1, C2
EN
L1
Description
Low Voltage 2MHz Step-Up Converter
Ceramic Capacitor: 4.7μF, 10V, 0603
Ceramic Capacitor: 4.7μF, 10V, 0805
Connecting Header, 2mm
2.2μH/1.62A Inductor
2.2μH/1.50A Inductor
Manufacturer
AnalogicTech
TDK
Taiyo Yuden
TDK
Murata
Taiyo Yuden
Sullins Electronics
Cooper Bussmann
Sumida
Table 2: Component Listing
EV146.2007.11.1.0
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EVALUATION BOARD DATASHEET
EV-146
AAT1265 EVAL: Low Voltage 2MHz Step-Up DC/DC Converter
Setup
1.
2.
3.
Configure the specified test equipment as shown in Figure 2, where Jumper 1 placement options are illustrated.
An additional 100μF or greater capacitor [CADD in Figure 2] may be required to decouple the input power supply and
maintain stable operation. Solder the additional capacitor to the VIN and GND terminals on the AAT1265 evaluation
board.
Input power supply with remote sense may be used. This simplifies the test procedure and maintains high accuracy of the input voltage across the loading range. Connect remote sense from input power source remote sense
terminals to the VIN and GND terminals on the AAT1265 evaluation board (optional, not shown in Figure 2).
2.000V
3.300V
Voltmeter
Voltmeter
Load
Power Supply
2.080V
0 – 250mA
0.550A
ADD
ON
OFF
Jumper 1
Jumper 1
Figure 2: AAT1265 Evaluation Board Connection Diagram with Jumper 1 Settings.
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EV146.2007.11.1.0
EVALUATION BOARD DATASHEET
EV-146
AAT1265 EVAL: Low Voltage 2MHz Step-Up DC/DC Converter
Evaluation/Testing
Enabling [Jumper 1 initially in ON position on EN]
1.
2.
Turn-Off
With input voltage applied, remove Jumper 1 and re-insert in the OFF position on EN. The output voltage should
decay to zero.
Turn-On
With input voltage applied, remove Jumper 1 on EN and re-insert in the ON position on EN. The output voltage
should recover to its nominal DC value of 3.3V.
Load and Line Regulation
1.
2.
3.
Enable the AAT1265 by placing Jumper 1 in the ON position on EN, as shown in Figure 2.
Turn on the input power supply and set to desired input voltage based on the DC voltmeter.
Vary the output load from 0 to 250mA (for a dual AA cell input) and vary the input voltage from 0.8V to VOUT while
monitoring the output voltage.
EV146.2007.11.1.0
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EVALUATION BOARD DATASHEET
EV-146
AAT1265 EVAL: Low Voltage 2MHz Step-Up DC/DC Converter
Printed Circuit Board
Figure 3: AAT1265 Evaluation Board Top Layer (not to scale).
Figure 4: AAT1265 Evaluation Board Bottom Layer (not to scale).
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.
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EV146.2007.11.1.0