19-4261; Rev 0; 8/08
MAX8517 Evaluation Kit
General Description
The MAX8517 evaluation kit (EV kit) is a fully assembled
and tested surface-mount PCB demonstrating the
MAX8517 low-dropout (LDO) regulator. The EV kit
comes assembled with a MAX8517EUB+ circuit that
steps down a 1.425V to 3.6V input-voltage range to a
1.2V output capable of sourcing up to 1A of continuous
output current, with a maximum dropout voltage of only
200mV. The MAX8517 features a POK output that goes
high impedance once the output is within ±10% of its
regulation value. Other features of the EV kit include a
logic-controlled shutdown mode (EN) and adjustable
output voltage through feedback resistors R1 and R2.
The EV kit can also be used to evaluate the MAX8518,
which features a POR output that goes high impedance
150ms (typ) after the output has risen above 90% of its
final value. Both the POK and POR features require an
external pullup resistor to IN. See the
Detailed
Description of Hardware
section for more details. To
evaluate the MAX8516, remove R4 and install a
MAX8516 IC.
Although the EV kit is optimized for 1A output current,
the part is capable of supporting up to 1.6A output cur-
rent (limited by power dissipation and dropout).
♦
1.425V to 3.6V Input-Voltage Range
♦
1.2V Output Voltage
♦
Up to 1.6A Output Current (Limited by Power
Dissipation and Dropout)
♦
Low-Dropout Voltage (200mV max at 1A)
♦
Power-OK (POK) Output (MAX8517 only)
♦
Power-On Reset (POR) Output (MAX8518 only)
♦
Fully Assembled and Tested
Features
Evaluates: MAX8516/MAX8517/MAX8518
Ordering Information
PART
MAX8517EVKIT+
TYPE
EV Kit
+Denotes
lead-free and RoHS compliant.
Component List
DESIGNATION
QTY
DESCRIPTION
1µF ±10%, 6.3V X5R ceramic
capacitor (0603)
TDK C1608X5R0J105K
Murata GRM188R60J105K
4.7µF ±10%, 16V X7R ceramic
capacitor (1206)
TDK C3216X7R1C475K
Murata GRM31CR71C475K
3-pin header
DESIGNATION
R1
R2
R3
R4
U1
—
—
QTY
1
1
1
1
1
1
1
DESCRIPTION
698Ω ±1% resistor (0603)
499Ω ±1% resistor (0603)
Not installed, resistor (0603)
100kΩ ±5% resistor (0603)
LDO regulator (10 µMAX
®
)
Maxim MAX8517EUB+
Shunts
PCB: MAX8517 Evaluation Kit+
C1
1
C2
1
JU1
1
Component Suppliers
SUPPLIER
Murata Electronics North America, Inc.
TDK Corp.
PHONE
770-436-1300
847-803-6100
WEBSITE
www.murata-northamerica.com
www.component.tdk.com
Note:
Indicate that you are using the MAX8516, MAX8517, or MAX8518 when contacting these component suppliers.
µMAX is a registered trademark of Maxim Integrated Products, Inc.
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
MAX8517 Evaluation Kit
Evaluates: MAX8516/MAX8517/MAX8518
Quick Start
Recommended Equipment
Before beginning, the following equipment is needed:
• One 4V, 1A variable-output power supply
• Dummy load capable of sinking 1A
•
Digital multimeter (DMM)
where V
FB
is 0.5V. Choose R2 < 1kΩ to optimize quies-
cent current, accuracy, and high-frequency power-sup-
ply rejection. To simplify resistor selection:
⎛
V
⎞
R1
=
R2
⎜
OUT
−
1
⎟
⎝
V
FB
⎠
Procedure
The MAX8517 EV kit is fully assembled and tested.
Follow the steps below to verify board operation.
Caution: Do not turn on power supplies until all con-
nections are completed.
1) Preset the power supply to 1.425V and turn off the
power supply.
2) Verify that a shunt is across pins 1-2 of JU1 to
enable the device.
3) Connect the positive lead of the power supply to
the VIN pad on the EV kit, and the negative lead of
the power supply to the GND pad on the EV kit.
4) Connect the positive input of the DMM to the VOUT
pad on the EV kit, and the negative input of the
DMM to the GND pad on the EV kit to measure the
output voltage.
5) Turn on the power supply and verify that the output
voltage is 1.2V ±1.4%.
6) Sweep the input voltage from 1.425V to 3.6V. Verify
that the output voltage is 1.2V ±1.4% over the entire
input range.
7) Set the power supply to 2V.
8) Connect the 1A load between the VOUT and GND
pads on the EV kit.
9) Verify that the output voltage is 1.2V ±1.4%.
Table 1. Jumper JU1 Functions
SHUNT POSITION
1-2*
2-3
EN PIN
Connected to IN
Connected to GND
MODE
Normal operation
Shutdown mode
*Default
position.
Shutdown Mode
The MAX8517 EV kit features 3-pin jumper JU1 to con-
trol the enable (EN) input. For normal operation, con-
nect EN to IN by placing a shunt across pins 1-2. To
shut down the device, pull EN to GND by placing a
shunt across pins 2-3. During shutdown, an internal
10kΩ resistor pulls down the output.
Power-OK (POK) (MAX8517 Only)
The MAX8517 EV kit features a power-OK (POK) output
to indicate the status of the output. The 100kΩ pullup
resistor (R4) pulls POK high when the regulator output
is within ±10% of its nominal output voltage. If the out-
put voltage falls or rises outside this range, POK transi-
tions low.
Power-On Reset (POR) (MAX8518 Only)
The EV kit can also evaluate the MAX8518 IC, which
features a power-on-reset output that transitions high
150ms (typ) after the output has risen above 90% of its
final value. If the part is in shutdown mode, falls below
90% of the nominal output voltage, or experiences a
short-circuit/thermal fault, POR immediately transitions
low. This open-drain output requires an external pullup
resistor to IN. Connect POR to IN by installing a 100kΩ
pullup resistor (R3).
Detailed Description of Hardware
Output Voltage Selection
The MAX8516/MAX8517/MAX8518 feature an
adjustable output voltage from 0.5V to 3.4V, using two
external resistors connected as a voltage-divider to FB,
as shown in Figure 1. The output voltage is set by the
following equation:
⎛
R1
⎞
V
OUT
=
V
FB
⎜
1
+
⎟
⎝
R2
⎠
2
_______________________________________________________________________________________
MAX8517 Evaluation Kit
Evaluates: MAX8516/MAX8517/MAX8518
Figure 1. MAX8517 EV Kit Schematic
_______________________________________________________________________________________
3
MAX8517 Evaluation Kit
Evaluates: MAX8516/MAX8517/MAX8518
Figure 2. MAX8517 EV Kit Component Placement Guide—
Component Side
Figure 3. MAX8517 EV Kit PCB Layout—Component Side
4
_______________________________________________________________________________________
MAX8517 Evaluation Kit
Evaluates: MAX8516/MAX8517/MAX8518
Figure 4. MAX8517 EV Kit PCB Layout—Solder Side
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 _____________________
5
© 2008 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products, Inc.
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