MAXIM MAX863EVKIT

19-1218; Rev 2; 2/98
MAX863 Evaluation Kit
The MAX863 evaluation kit (EV kit) is an assembled and
tested PC board that demonstrates the MAX863 dual,
step-up DC-DC controller. The EV kit is factory preset to
provide 5V and 3.3V outputs at 700mA and 1.1A,
respectively (VIN = 2.4V). Both outputs can also be set to
other voltages by pin-strapping or with external resistors.
____________________Component List
DESIGNATION QTY
C1
1
____________________________Features
♦ Output Voltages: Preset 5V and 3.3V, or
User-Defined
♦ Output Currents:
700mA at 5V, 1.1A at 3.3V (VIN = 2.4V)
350mA at 5V, 600mA at 3.3V (VIN = 1.5V)
♦ Low-Battery Detector
♦ Fully Assembled and Tested
♦ Proven PC Board Layout
DESCRIPTION
330µF, 10V tantalum capacitor
0.060Ω max ESR
Sprague 594D337X0010R2
C2, C9
2
100µF, 16V tantalum capacitor
0.1Ω max ESR
AVX TPSE107M016R0100
C3, C6, C10, C11
0
Open
C4
1
10µF, 16V tantalum capacitor
C5
______________Ordering Information
PART
MAX863EVKIT
TEMP. RANGE
0°C to +70°C
BOARD TYPE
Surface Mount
______________Component Suppliers
PHONE
FAX
AVX
(803) 626-3123
1
220µF, 16V tantalum capacitor
0.060Ω max ESR
Sprague 594D227X0016R2
(803) 946-0690
(800) 282-4975
Dale
(605) 668-4131
(605) 665-1627
International Rectifier
(310) 322-3331
(310) 322-3332
C7, C8
1
0.1µF ceramic capacitor
IRC
(512) 992-7900
(512) 992-3377
D1, D2
2
3A, 40V Schottky diode
Motorola MBRS340T3
Motorola
(602) 303-5454
(602) 994-6430
JU1–JU5
5
3-pin headers
L1, L2
2
10µH, 2.5A inductor
Sumida CD75-10uH (2.3A, 0.07Ω)
R1, R3, R7, R9
0
Open
R2, R4
2
0.050Ω, 1% sense resistor
Dale WSL-2010-0.050Ω ±1% or
IRC LR2010-R050-F
R5
1
165kΩ, 1% resistor
R6, R8
2
100kΩ, 1% resistors
U1
1
Maxim MAX863EEE
U2
1
Dual, logic-level N-channel FET
International Rectifier IRF7301
(VT < 0.70V, RDS(ON) = 0.070Ω at 2.7V)
None
1
PC board
SUPPLIER*
Sprague
Sumida
(603) 224-1961
(603) 224-1430
USA
(847) 956-0666
(847) 956-0702
Japan
81-3-3607-5111
81-3-3607-5144
*Please indicate that you are using the MAX863 when contacting these suppliers.
_________________________Quick Start
This section describes how to operate the MAX863 EV
kit and evaluate its performance. Do not turn on the
power supply until all connections are completed.
1) Configure the jumpers in accordance with Table 1.
2) Connect a 1.5V to 3.3V DC power supply between
the VIN and GND input pads.
3) Turn on the power supply. With no load and the output in regulation, supply current for the board should
be less than a few hundred microamperes.
4) Measure the output voltage at OUT1. With FB1 =
GND (JU3 = 1-2), OUT1 will be preset to 5V.
5) Measure the output voltage at OUT2. The standard
factory setting of R5 = 165kΩ and R6 = 100kΩ sets
OUT2 to 3.3V.
________________________________________________________________ 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: MAX863
_______________General Description
Evaluates: MAX863
MAX863 Evaluation Kit
_Detailed Description of Hardware
Adjustable Output Voltage
OUT2 must be set with a resistor divider. The EV kit
board provides R5 and R6 for this purpose. OUT1 can
be set with a resistor divider (R1 and R3) or configured
for a preset value (JU3). The EV kit board is preset for a
5.0V output.
To configure OUT1 for an adjustable output, open
jumper JU3 and then install resistors at sites R1 and
R3. Select the resistors according to the following formulas:
R1 / R3 = (VOUT1 / VREF) - 1
The EV kit board provides space at C3, C6, C10, and
C11 for optional compensation capacitors. Refer to the
Set Feedback Compensation section in the MAX863
data sheet for more information.
Low-Battery Detector
The EV kit board provides pads at R7 and R8 for an
optional resistor divider for the low-battery voltage
detector. When the voltage at the LBI pin falls below
1.25V, the LBO pin is pulled low. Select the resistors
according to the following formula:
R7 / R8 = (VLOW / VREF) - 1
where VREF = 1.25V.
R5 / R6 = (VOUT2 / VREF) - 1
where VREF = 1.25V.
Note: Output capacitors C1 and C5 are rated for 10V
and 16V, respectively. For higher output voltages,
replace these capacitors.
Table 1. Jumper Settings
FUNCTION
BOOT Pin
VDD Select
OUT1 Set
JUMPER
STATE
DESCRIPTION
1-2*
BOOT = VDD; bootstrapped mode (VIN < 2.7V).
If BOOT is high, VDD must be connected to OUT1.
2-3
BOOT = GND; non-bootstrapped mode (VIN > 2.7V).
When using a non-bootstrapped circuit configuration,
connect BOOT to GND.
1-2*
VDD = OUT1; bootstrapped mode (VIN < 2.7V)
2-3
VDD = VIN; non-bootstrapped mode (VIN > 2.7V)
1-2*
FB1 = GND; OUT1 set to 5V; R1 and R3 should be open.
2-3
FB1 = VDD; OUT1 set to 3.3V; R1 and R3 should be open.
JU1
JU2
JU3
Open
OUT1
Shutdown
JU4
OUT2
Shutdown
JU5
OUT1 determined by R1 and R3
1-2*
SHDN1 = VDD; OUT1 enabled
2-3
SHDN1 = GND; OUT1 disabled; OUT1 and OUT2 can be
independently disabled.
1-2*
SHDN2 = VDD; OUT2 enabled
2-3
SHDN2 = GND; OUT2 disabled
* Indicates default factory settings.
2
_______________________________________________________________________________________
GND
OUT1
GND
1
C9
100µF
16V
C10
OPEN
3
GND
U2B
IRF7301
3
D1
MBRS340T3
L1
10µH
2.5A
C1
330µF
10V
VIN
FB1
C3
OPEN
5
FB1
OPEN
2
JU3
OPEN
1
V DD
R3
2
R1
OUT1
JU2
3
4
R2
0.050Ω
6
V DD
BOOT
3
2
JU1
VDD
SENSE1
MAX863
U1
C7
0.1µF
SHDN2
SHDN1
GND
J2-5
J2-6
LBO
REF
J2-3
J2-4
VDD
9
10
11
12
13
14
15
16
J2-2
EXT2
CS2
SHDN1
FB2
LBI
LBO
REF
SHDN2
C8
0.1µF
J2-1
TEST POINTS
FB1
4 BOOT
5
CS1
6
EXT1
7
GND
8
PGND
3
2
1
C4
10µF
16V
1
R4
0.050Ω
2
8
1
REF
L2
10µH
2.5A
C5
220µF
16V
D2
IRF7301 MBRS340T3
U2A
7
C6
OPEN
3
JU5 1
SHDN2 2
C2
100µF
16V
3
JU4 1
SHDN1 2
VIN
R5
165k
1%
R6
100k
1%
GND
OUT2
R8
100k
1%
R7
OPEN
R9
OPEN
C11
OPEN
LBO
VIN
Evaluates: MAX863
VIN
MAX863 Evaluation Kit
Figure 1. MAX863 EV Kit Schematic Diagram
_______________________________________________________________________________________
3
Evaluates: MAX863
MAX863 Evaluation Kit
1.0"
1.0"
Figure 2. MAX863 EV Kit Component Placement Guide—
Component Side
1.0"
Figure 3. MAX863 EV Kit Component Placement Guide—
Solder Side
1.0"
Figure 4. MAX863 EV Kit PC Board Layout—Component Side
Figure 5. MAX863 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
© 1998 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.