AOSMD AOZ1017-EVA

AOZ1017-EVA
EZBuck™ 3A Simple Buck Regulator
Evaluation Board Note
General Description
Features
The AOZ1017 evaluation board is a fully assembled and
tested circuit board built with the AOZ1017 buck regulator
IC. It outputs a preset or adjustable voltage and up to 3A
of continuous current. The evaluation board requires an
input voltage from 4.5V to 16V. The output voltage is
preset and can be adjusted from 0.8V to VIN–0.4V
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The AOZ1017-EVA circuit features include; current limit,
short circuit protection, input under voltage lock out,
internal soft start and thermal shut down. It operates at a
fixed 500kHz switching frequency. The current mode
control and integrated internal MOSFET minimize
component count, board area and total cost.
The AOZ1017 comes in SO-8 packages and is rated over
a -40°C to +85°C ambient temperature range.
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4.5V to 16V operating input voltage range
Output voltage was preset to 3.3V, adjustable down to
0.8V
3A continuous output current
Fixed 500kHz PWM operation
Internal soft start
Cycle-by-cycle current limit
Short-circuit protection
Thermal shutdown
Applications
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Point of load DC/DC conversion
PCIe graphics cards
Set top boxes
DVD drives and HDD
LCD panels
Cable modems
Telecom/networking/datacom equipment
Evaluation Board Schematic
VIN
C1
22µF
C6
NC
VIN
From µPC
L1
U1
EN
AOZ1017
C4
NU
COMP
RC
CC
C5
1000pF
FB
AGND
VOUT
LX
GND
D1
R1
C2
22µF
C3
22µF
R2
10kΩ
Figure 1.
Rev. 1.0 October 2007
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AOZ1017-EVA
Component List
Ref
Designation
Value
Description
Manufacturer
Part Number
C1
22µF
Ceramic Cap, 22µF, 25V, 1210, X5R
GRM32ER61E226KE15L
C2
22µF
Ceramic Cap, 22µF, 25V, 1210, X5R
GRM32ER61E226KE15L
C3
22µF
Ceramic Cap, 22µF, 25V, 1210, X5R
GRM32ER61E226KE15L
C4
NU
C5
1000pF
Ceramic Cap, 1000pF, 50V, 0603, X7R
GRM188R71E102K
Manufacturer
Murata
C6
NU
CC
1000pF
Ceramic Cap, 1000pF, 50V, 0603, X7R
GRM188R71E222K
RC
20kΩ
Thick Film Res, 1%, 20k, 0603
CRCW060331K6FKTAP
R1(1)
31.6kΩ
Thick Film Res, 1%, 31.6k, 0603
CRCW060320K0FKTAP
R2
10kΩ
Thick Film Res, 1%, 10k, 0603
CRCW060310K0FKTAP
L1
4.7µH
Inductor, 4.7µH, 6.4A
MSS1278-472MLD
Coilcraft
Schottky Diode IF(av) = 5A, SMD
PDS540-13
Diodes
Buck Regulator IC, 3A, 16V
AOZ1017AI
AOS
D1
U1
AOZ1017AI
DALE
Note:
1. VO is preset to 3.3V. Output voltage is set by R1; R1 = (12.5 x VO) – 10kΩ. Table 1 shows that the value of R1 with typical output
voltages.
Table 1.
Vo (V)
R1 (kΩ)
1.2
4.99
1.8
12.7
2.5
21.5
3.3
31.6
5.0
52.3
Rev. 1.0 October 2007
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AOZ1017-EVA
PCB Layout
Figure 1. Top Silk Screen
Figure 2. Top Layer
Figure 3. Bottom Layer
Rev. 1.0 October 2007
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AOZ1017-EVA
Quick Start Guide
1. Connect the terminals of load to +VOUT pins and GND pins. Set load current to between 0A and 3A.
2. Connect the DC power supply to +VIN pin and GND pins. Set DC power supply voltage to between 4.5V and 16V.
3. Connect EN pin to +VIN or any voltage source which is higher than 2V and less than 16V.
4. Turn on DC power supply and evaluation circuit will start.
5. Measure input voltage at the +VIN pin and GND pins to eliminate the effect of voltage drop on wire between DC
power supply and evaluation board.
6. Measure output voltage at the +VOUT pin and GND pins to eliminate the effect of voltage drop on wire between load
and evaluation board.
7. Use an oscilloscope to monitor input ripple voltage right across input capacitor C1.
8. Use an oscilloscope to monitor output ripple voltage right across output capacitor C2.
This datasheet contains preliminary data; supplementary data may be published at a later date.
Alpha & Omega Semiconductor reserves the right to make changes at any time without notice.
LIFE SUPPORT POLICY
ALPHA & OMEGA SEMICONDUCTOR PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL
COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS.
As used herein:
1. Life support devices or systems are devices or
systems which, (a) are intended for surgical implant into
the body or (b) support or sustain life, and (c) whose
failure to perform when properly used in accordance
with instructions for use provided in the labeling, can be
reasonably expected to result in a significant injury of
the user.
Rev. 1.0 October 2007
2. A critical component in any component of a life
support, device, or system whose failure to perform can
be reasonably expected to cause the failure of the life
support device or system, or to affect its safety or
effectiveness.
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