19-1864; Rev 0; 11/00
MAX1817 Evaluation Kit
General Description
The MAX1817 evaluation kit (EV kit) is a fully assembled
and tested surface-mount circuit board that demon-
strates the MAX1817 dual-output, step-up DC-DC con-
verter. The main output is configured for +3.3V and pro-
vides up to 125mA of current. The LCD bias output is
configured for +18.0V and provides up to 10mA. The
EV kit can support the dual output with a +1.5V to
+3.3V input voltage range.
o
Dual Output Voltages
+3.3V Main Output
+18V LCD Bias Output
o
Adjustable Output Voltages
o
125mA Available from the Main Output
o
10mA Available from the LCD Bias Output
o
Input Voltage as Low as +1.5V
o
Low 15µA Quiescent Supply Current
o
Surface-Mount Construction
Features
Evaluates: MAX1817
Component List
DESIGNATION
QTY
DESCRIPTION
10µF, 6.3V, X5R ceramic
capacitor (1206)
Taiyo Yuden JMK316BJ106ML or
TDK C3216X5R0J106KT
1µF, 35V, X7R ceramic
capacitor (1206)
Taiyo Yuden GMK316BJ105ML or
equivalent
22µF, 6.3V, X5R ceramic
capacitor (1210)
Taiyo Yuden JMK325BJ226MM
5.0pF, 50V ceramic capacitor (0603)
Murata GRM39COG050B050 or
Taiyo Yuden UMK107CH050CZ
Not installed (0603)
1MΩ
±1%
resistor (0805)
75kΩ
±1%
resistor (0805)
Not installed (0805)
200mA, 75V junction diode (SOT-23)
Central Semiconductor CMPD4448
0.5A, 30V Schottky diode (SOD-123)
Nihon EP05Q03L
10µH, 1A inductors
Sumida CR43-100MC
MAX1817EUB (10-pin
µMAX)
3-pin headers
Shunts (JU1, JU2)
MAX1817 PC board
MAX1817 data sheet
MAX1817 EV kit data sheet
o
Fully Assembled and Tested
Ordering Information
PART
MAX1817EVKIT
TEMP. RANGE
0°C to +70°C
IC PACKAGE
10 µMAX
C1
1
Component Suppliers
SUPPLIER
Central Semiconductor
Murata
Nihon
Sumida
Taiyo Yuden
TDK
PHONE
631-435-1110
814-237-1431
661-867-2555
847-956-0666
408-573-4150
847-803-6100
FAX
631-435-3388
814-238-0490
661-867-2698
847-956-0702
408-573-4159
847-803-6296
C2
1
C3
1
C4
C5, C6
R1
R2
R3, R4
D1
D2
L1, L2
U1
JU1, JU2
None
None
None
None
1
0
1
1
0
1
1
2
1
2
2
1
1
1
Note:
Please indicate that you are using the MAX1817 when
contacting these component suppliers.
Quick Start
The MAX1817 EV kit is a fully assembled and tested
surface-mount board. Follow the steps below for board
operation.
Do not turn on the power supply until all
connections are completed.
1) Verify that shunts are across pins 1 and 2 of
jumpers JU1 and JU2 to enable the main output
and the LCD output, respectively.
2) Connect a voltmeter across the VOM pad and the
nearest GND pad to monitor the main output voltage.
3) Connect a voltmeter across the VOLCD pad and
the nearest GND pad to monitor the LCD output
voltage.
4) Connect a +1.5V to +3.3V supply to the VBATT
pad. Connect the ground to the GND pad.
5) Turn on the power supply and verify that the main
output VOM is at +3.3V and the VOLCD output is at
+18.0V.
1
________________________________________________________________
Maxim Integrated Products
For price, delivery, and to place orders, please contact Maxim Distribution at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
MAX1817 Evaluation Kit
Evaluates: MAX1817
Detailed Description
The MAX1817 EV kit is a fully assembled and tested
surface-mount circuit containing a dual-output, step-up
DC-DC converter. The main output (VOM) is configured
to supply 125mA (typ) at +3.3V, and the LCD bias out-
put (VOLCD) is configured to supply 10mA (typ) at
+18.0V. The circuit requires a power supply with a
+1.5V to +3.3V input voltage range. VOM and VOLCD
output voltages are adjustable with external resistors.
the PCB short (located at R4) and installing resistors R3
and R4. Refer to the
Setting the Main Output Voltage
section of the MAX1817 data sheet for instructions on
selecting R3 and R4.
The +18.0V LCD bias output voltage is set with voltage-
divider resistors R1 and R2. These resistors divide the
output voltage to the +1.25V LCD feedback regulation
threshold at FBLCD. The output can be adjusted to a
maximum of +28.0V by replacing resistors R1 and R2.
Refer to the
Setting the LCD Output Voltage
section of
the MAX1817 data sheet for instructions on selecting
R1 and R2.
Input Source
The MAX1817 EV kit requires a +1.5V to +3.3V voltage
input to maintain the main output voltage at +3.3V and
the LCD bias output voltage at +18.0V. However, if the
input voltage is raised to the +5.5V maximum input, the
VOM output voltage will increase to equal the input
voltage minus the diode (D2) voltage drop. At the
+5.5V maximum input voltage, the VOLCD output volt-
age will remain steady at +18.0V.
Enable/Disable
The EV kit contains two 3-pin jumpers (JU1 and JU2)
that allow the user to enable and disable the main out-
put (VOM) or the LCD output (VOLCD). Refer to Table 1
for jumper configuration. Note that the main output volt-
age must be at least +2.5V to enable the LCD output.
Adjustable Outputs
The VOM output voltage is set to +3.3V by a PCB short
from FB to ground. The output voltage can be adjusted
to a different voltage (+2.5V to +5.5V) by cutting open
Table 1. Jumper JU1 Functions
JUMPER
JU1
2 and 3
1 and 2
JU2
2 and 3
ONLCD connected to GND
VOLCD output disabled
ON connected to GND
ONLCD connected to VOM
VOM output disabled
VOLCD output enabled
STATUS
1 and 2
PIN CONNECTION
ON connected to VOM
EV KIT OPERATION
VOM output enabled
2
_______________________________________________________________________________________
MAX1817 Evaluation Kit
Evaluates: MAX1817
L1
10µH
C1
10µF
L2
10µH
VOM
U1
1
2
3
JU1
2
ON
MAX1817
7
LXLCD
6*
NC
OUT
10
C6
OPEN
JU2
3
ONLCD
FBLCD
4
C5
OPEN
R3
OPEN
C3
22µF
LX
9
D2
R2
75k
1%
VBATT
(+1.5V TO +3.3V)
D1
R1
1M
1%
C2
1.0µF
VOLCD
(+18.0V)
GND
C4
5.0pF
GND
VOM
(+3.3V)
VOM
1
2
3
FB 1
AGND
5
GND
8
R4
SHORTED
(PC BOARD TRACE)
* NC CONNECTION NOT REQUIRED
Figure 1. MAX1817 EV Kit Schematic
1.0"
Figure 2. MAX1817 EV Kit Component Placement Guide—
Component Side
1.0"
Figure 3. MAX1817 EV Kit PC Board Layout—Component Side
_______________________________________________________________________________________
3
MAX1817 Evaluation Kit
Evaluates: MAX1817
1.0"
Figure 4. MAX1817 EV Kit PC Board 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.
4
_____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600
© 2000 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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