MAXIM MAX1830EVKIT

19-2198; Rev 1; 9/02
MAX1830 Evaluation Kit
Features
♦ Delivering 3A Output Current
94% Efficiency
♦ Synchronous Rectifier Improves Efficiency
♦ Output Voltage Preset to 1.8V
♦ 1.5V, 1.8V, or 2.5V Selectable
1.1V to VIN Adjustable
♦ 3V to 5.5V Input Voltage Range
♦ No External Schottky Diode Required
♦ Less than 1µA (typ) IC Shutdown Current
♦ Surface-Mount Construction
♦ Fully Assembled and Tested
Ordering Information
Component List
PART
DESIGNATION
QTY
DESCRIPTION
C1
1
22µF, 6.3V ceramic capacitor (1210)
TDK C3225X5R0J226M
C2
1
2.2µF, 10V ceramic capacitor (0805)
TDK C2012X5R1A225M or
Taiyo Yuden LMK212BJ225MG
C3
1
470pF ceramic capacitor (0603)
C4
1
1µF, 10V ceramic capacitor (0805)
TDK C2012X5R1A105M or
Taiyo Yuden LMK212BJ105MG
C5
1
120µF, 4V, SP capacitor
Panasonic EEFUD0G121R
D1
1
Schottky diode
(not installed)
L1
1
1.5µH inductor
Sumida CDRH6D28–4762T064
R1
1
10Ω ±5% resistor (0603)
R2
1
1MΩ ±5% resistor (0603)
R3
1
84.5kΩ ±1% resistor (0805)
R4
1
Not installed (0805)
R5
1
Not installed (0805)
U1
1
MAX1830EEE (16-pin QSOP)
JU1
1
2-pin header
JU2
1
4-pin header
JU3
0
Not installed (shorted with PC board
trace)
None
2
Shunts
MAX1830EVKIT
TEMP RANGE
0°C to +70°C
IC PACKAGE
16 QSOP
Component Suppliers
SUPPLIER
PHONE
FAX
Panasonic
201-392-7522
201-392-4441
Sumida
847-956-0666
847-956-0702
Taiyo Yuden
408-573-4150
408-573-4159
TDK
847-803-6100
847-803-6296
Note: Please indicate that you are using the MAX1830 when
contacting these component suppliers.
Quick Start
The MAX1830 EV kit is a fully assembled and tested
surface-mount board. Follow the steps below for proper
board operation. Do not turn on the power supply
until all connections are completed:
1) Connect a voltmeter and load (if any) from VOUT to
GND.
2) Verify that there is a shunt on JU1 (shutdown disabled).
3) Verify that the JU2 shunt is connected across pins
1 and 4 to set the output to 1.8V.
4) Connect a 3V to 5.5V supply to the pads marked
VIN and GND (supply off).
5) Turn on the power supply and verify that the output
voltage is 1.8V.
6) See the Output Voltage Selection section to modify
the board for a different output voltage.
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
Evaluates: MAX1830/MAX1831
General Description
The MAX1830 evaluation kit (EV kit) provides a 1.8V
output from a 3V to 5.5V input voltage source. It delivers up to 3A output current with a 94% (max) efficiency.
The MAX1830 EV kit includes the MAX1830 step-down
switching regulator with an internal synchronous rectifier to increase efficiency and reduce the number of
external components. The resistor-programmable fixedoff-time, current-mode architecture allows an optimum
response to load and line transients. This EV kit, as
configured, operates at approximately 550kHz from
3.3V inputs and 770kHz from 5V inputs.
The MAX1830 EV kit can be configured to produce a
preset output voltage of 1.5V, 1.8V, 2.5V, or is feedback
adjustable from 1.1V to VIN.
This EV kit can also be used to evaluate the MAX1831
with preset output voltages of 1.5V/1.8V and 3.3V, or
adjustable output voltage from 1.1V to VIN.
Evaluates: MAX1830/MAX1831
MAX1830 Evaluation Kit
Detailed Description
The MAX1830 EV kit can be configured to produce a
preset output voltage of 1.5V, 1.8V, 2.5V, or is feedback
adjustable from 1.1V to VIN. As configured, the kit is
preset for 1.8V. It operates from an input voltage range
of 3V to 5.5V and delivers up to 3A of output current.
Jumper Selection
Jumper JU1 controls the MAX1830’s shutdown function. Table 1 lists the jumper options.
Output Voltage Selection
The output voltage can be modified from the preset
1.8V output voltage two different ways. The first way is
to change the output voltage to one of the other preset
output voltages (1.5V or 2.5V). This is done by changing
the jumper JU2 setting (Table 2). The second way is to
add feedback resistors (R4 and R5) and connect
FBSEL to GND, which allows an adjustable output voltage of 1.1V to VIN.
Note: Adjustable operation may require replacement of
C5 with output capacitor rated for higher voltage.
The resistors can be calculated according to the following equation:
Table 1. Jumper JU1 Function
SHUNT
LOCATION
SHDN PIN
Open
Logic low: 1MΩ
pulldown resistor
Output voltage
disabled
Closed
(Default)
Connected to VIN
Output voltage
enabled
Table 2. Output Voltage Configuration
OUTPUT
VOLTAGE (V)
JU2
1.5
Not installed
(FBSEL = OPEN)
Installed (preset
output voltage)
1.8 (MAX1830)*
3.3 (MAX1831)
Connect 1 and 4
(FBSEL = REF)
Installed (preset
output voltage)
2.5
Connect 1 and 2
(FBSEL = VCC)
Installed (preset
output voltage)
Adjustable
Connect 1 and 3
(FBSEL = GND)
Not installed (JU3 PC
board trace must be
cut) (output voltage
set by R4 and R5)
R4 = (VOUT x R5 / 1.1V ) - R5
Select R5 between 10kΩ and 25kΩ.
MAX1830 OUTPUT
JU3
*Default setting.
The inductor provided in the MAX1830 EV kit is optimized for a 3V to 5.5V input voltage range and a
1.8V/3A output voltage. If the output needs to be
changed to another output voltage, refer to the
MAX1830 data sheet for the recommended inductor
value for your application.
2
_______________________________________________________________________________________
MAX1830 Evaluation Kit
VIN
GND
R1
10Ω
1
LX
3
LX
14
LX
16
LX
2 IN
4 IN
C1
22µF
12
C2
2.2µF
VCC
PGND
SHDN
R2
1MΩ
1.8V/3A
OUT
R4
OPEN
JU3
D1
OPEN
JU1
5
L1
1.5µH
PGND
U1
MAX1830
FB
Evaluates: MAX1830/MAX1831
3V TO 5.5V
C5
120µF
GND
13
15
8
R5
OPEN
6
7
C3
470pF
COMP
TOFF
REF
R3
84.5kΩ
GND
10
9
FBSEL
11
JU2
2 1
4
3
C4
1µF
Figure 1. MAX1830 EV Kit Schematic
_______________________________________________________________________________________
3
Evaluates: MAX1830/MAX1831
MAX1830 Evaluation Kit
1.0"
1.0"
Figure 2. MAX1830 Component Placement Guide—
Component Side
Figure 3. MAX1830 EV Kit PC Board Layout—Component Side
1.0"
Figure 4. MAX1830 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
© 2002 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.