19-1462; Rev 0; 6/99
MAX618 Evaluation Kit
General Description
The MAX618 evaluation kit (EV kit) is a constant-fre-
quency, PWM, step-up switching regulator with an
internal 2A, 28V n-channel MOSFET. The EV kit accepts
a +3V to V
OUT
input and converts it to a 12V output for
currents up to 500mA. Conversion efficiency is greater
than 90%. The EV kit operates at 250kHz, allowing the
use of small external components.
The MAX618 EV kit is a fully assembled and tested sur-
face-mount circuit board.
o
+3V to V
OUT
Input Voltage Range
o
12V or Adjustable Output Voltage
o
Up to 500mA Output Current
o
Internal 2A, 28V MOSFET Switch
o
3µA Shutdown Current
o
250kHz Switching Frequency
o
Surface-Mount Components
o
Fully Assembled and Tested
Features
Evaluates: MAX618
Component List
DESIGNATION QTY
C1, C2
C3
C4
C5
C6, C7
C8
2
1
1
1
2
1
DESCRIPTION
68µF, 20V low-ESR tantalum caps
AVX TPSE686M020R0150 or
Sprague 593D686X0020E2W
0.1µF ceramic capacitor
4.7µF, 10V X5R ceramic capacitor
Taiyo Yuden LMK316BJ475ML
0.047µF ceramic capacitor
1µF, 25V X5R ceramic capacitors
Taiyo Yuden TMK316BJ105KL
68pF ceramic capacitor
2A Schottky diode
SGS-Thomson STPS2L25U,
Nihon EC21QS03L, or
Central Semiconductor CMSH2-40M
15µH power inductor
Sumida CDRH6D38-150 (shielded),
Sumida CR75-150 (unshielded), or
Sumida CDH74-150 (unshielded)
715kΩ ±1% resistor
100kΩ ±1% resistor
MAX618EEE
3-pin header
Shunt
MAX618 PC board
MAX618 data sheet
PART
MAX618EVKIT
Ordering Information
TEMP. RANGE
0°C to +70°C
IC PACKAGE
16 QSOP
_________________________Quick Start
The MAX618 EV kit is fully assembled and tested.
Follow these steps to verify board operation.
Do not
turn on the power supply until all connections are
completed.
1) Connect a +5V supply to the VIN pad. Connect
ground to the GND pad.
2) Connect a voltmeter and load, if any, to the VOUT
pad.
3) Place the shunt across JU1 pins 2 and 3.
4) Turn on the power supply to the board and verify
that the output voltage is 12V.
5) For other output voltages, refer to the
Output
Voltage Selection
section in the MAX618 data sheet
for instructions on selecting feedback resistors R1
and R2, inductor L1, output capacitor C2, and com-
pensation capacitors C5 and C8.
Note:
Input (C1)
and output (C2) capacitors are rated at 20V.
D1
1
L1
1
R1
R2
U1
JU1
None
None
None
1
1
1
1
1
1
1
Jumper Selection
The 3-pin header JU1 selects shutdown mode. Table 1
lists the selectable jumper options in shutdown mode.
Table 1. Jumper JU1 Shutdown Function
SHUNT
LOCATION
1&2
2&3
SHDN
PIN
Connected to
GND
Connected to
VL
MAX618 OUTPUT
Shutdown mode,
V
OUT
= V
IN
- V
DIODE
MAX618 enabled,
V
OUT
= 12V
1
________________________________________________________________
Maxim Integrated Products
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
