19-3080 Rev 2; 12/06
MAX1272 Evaluation Kit/Evaluation System
General Description
The MAX1272 evaluation system (EV system) is a com-
plete, 12-bit, multirange, single-channel, data-acquisi-
tion system consisting of a MAX1272 evaluation kit (EV
kit), Maxim 68HC16MODULE-DIP microcontroller (µC)
module, and USBTO232.
Order the complete EV system (MAX1272EVC16) for a
comprehensive evaluation of the MAX1272 using a per-
sonal computer (PC). Order the EV kit (MAX1272EVKIT)
separately if the 68HC16MODULE-DIP module has
already been purchased with a previous Maxim EV sys-
tem or for custom use in other µC-based systems.
The MAX1272 EV kit can also be used to evaluate the
MAX1273CPA (8-pin DIP).
♦
Proven PC Board Layout
♦
Convenient On-Board Test Points
♦
Fully Assembled and Tested
♦
EV Kit Software Supports Windows
®
98/2000/XP
with RS-232/COM Ports
♦
EV Kit Software Supports Windows 2000/XP with
USB Ports
Features
Evaluate: MAX1272/MAX1273
Ordering Information
PART
MAX1272EVKIT
MAX1272EVC16
TEMP RANGE
0°C to +70°C
0°C to +70°C
INTERFACE TYPE
User supplied
Windows software
MAX1272EVKIT Software
PROGRAM
INSTALL.EXE
KIT1272.C16
MAX1272.EXE
FUNCTION
Installs the EV kit files on your
computer.
Software loaded into 68HC16
µC module.
Application program.
Note:
The MAX1272 EV kit software is designed for use with
the complete EV system. It includes the µC module,
USBTO232, and the EV kit. If the Windows software is not
used, the EV kit board can be purchased by itself, without the
µC module.
Note:
To evaluate the MAX1273, request a free sample of the
MAX1273CPA when ordering the MAX1272 EV kit.
MAX1272EVKIT Component List
DESIGNATION
C1, C3
C2
J1
TB0
TP1
U1
—
—
QTY
2
1
1
1
1
1
1
1
DESCRIPTION
1µF ceramic capacitors (0805)
TDK C2012X5R1C105M
0.1µF ceramic capacitor (0603)
2 x 20 right-angle female connector
Two-circuit terminal block
6-pin header
MAX1272CPA (8-pin DIP)
MAX1272 EV kit PCB
MAX1272 EV kit software, CD-ROM
Quick Start
USB Port PC Connection Option
Note:
In the following section(s), software-related
items are identified by bolding. Text in
bold
refers to
items directly from the EV kit software. Text in
bold
and underlined
refers to items from the Windows
98SE/2000/XP operating system.
• MAX1272EVC16
(MAX1272EVKIT
board,
USBTO232, and 68HC16MODULE-DIP)
• A DC power supply (+8V to +20V)
• A PC running Windows 2000/XP with an available
standard USB port to connect to the USBTO232
• USB cable included with the USBTO232
1) Visit the Maxim website (www.maxim-ic.com) to
download the latest version of the USBTO232 user
guide. Follow the steps in the USBTO232 user
guide quick start section and return to step 2 of this
Quick Start
section when finished.
2) Carefully connect the boards by aligning the 40-pin
connector of the MAX1272EVKIT with the 40-pin
header of the 68HC16MODULE-DIP module.
Gently press them together. The two boards should
be flush against one another.
1
MAX1272EVC16 System
PART
MAX1272EVKIT
68HC16MODULE-DIP
USBTO232+
QTY
1
1
1
DESCRIPTION
MAX1272 EV kit
68HC16 µC module
USB-to-RS-232 converter
board
Windows is a registered trademark of Microsoft Corp.
________________________________________________________________
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.
MAX1272 Evaluation Kit/Evaluation System
Evaluate: MAX1272/MAX1273
3) Ensure that the 68HC16MODULE-DIP module’s
SW1 switch is in the OFF position.
4) Connect the +8V to +20V power supply to the
68HC16MODULE-DIP module’s terminal block (J2)
located next to SW1. Observe the polarity marked
on the board.
5) Connect the USBTO232 board to the
68HC16MODULE-DIP module if you have not done
so already.
6) The MAX1272 EV kit software should have already
been downloaded and installed in the USBTO232
user guide quick start.
7) Start the MAX1272 program by opening its icon in
the
Start | Programs
menu.
8) Slide SW1 to the ON position. Click OK, the
Windows program automatically downloads
KIT1272.C16 to the module.
9) Apply an input signal (0 to 10V) between AIN and
GND. Observe the readout on the running Windows
program.
4) Ensure that the 68HC16MODULE-DIP module’s
SW1 switch is in the OFF position.
5) Connect the +8V to +20V power supply to the
68HC16MODULE-DIP module’s terminal block (J2)
located next to SW1. Observe the polarity marked
on the board.
6) Connect a standard serial cable from the comput-
er’s serial port to the 68HC16MODULE-DIP module.
If the PC’s standard serial port has a 9-pin connec-
tor, use a straight-through, 9-pin female-to-male
cable. If the PC’s only available standard serial port
has a 25-pin connector, a standard 25-pin to 9-pin
adapter is required. The EV kit software checks the
modem status lines (CTS, DSR, DCD) to confirm
that the correct port has been selected.
7) Start the MAX1272 program by opening its icon in
the
Start | Programs
menu.
8) Turn on the power supply and slide SW1 to the ON
position on the 68HC16MODULE-DIP module. Click
the OK button to automatically connect and down-
load the file KIT1272.C16 to the module.
9) Apply an input signal (0 to 10V) between AIN and
GND. Observe the readout on the running Windows
program.
RS-232/COM Port PC Connection Option
• MAX1272EVC16 (MAX1272EVKIT board and
68HC16MODULE-DIP)
• A DC power supply (+8V to +20V)
• A PC running Windows 98/2000/XP with an available
standard serial port, preferably with a 9-pin plug
• A standard serial cable to connect the PC’s stan-
dard serial port to the 68HC16MODULE-DIP module
1) Visit the Maxim website (www.maxim-ic.com/evkit-
software) to download the latest version of the EV kit
software. Save the EV kit software to a temporary
folder and uncompress the file (if it is a .zip file).
2) Install the MAX1272 EV kit software on your com-
puter by running the INSTALL.EXE program. The
program files are copied and icons are created for
them in the Windows
Start | Programs
menu.
3) Carefully connect the boards by aligning the 40-pin
connector of the MAX1272EVKIT with the 40-pin
header of the 68HC16MODULE-DIP module. Gently
press them together. The two boards should be
flush against one another.
Detailed Description
MAX1272 Stand-Alone EV Kit
The MAX1272EVKIT provides a proven PCB layout to
evaluate the MAX1272. It must be interfaced to appropri-
ate timing signals for proper operation. Connect +5V to
V
DD
and connect ground return to GND. See Figure 2
(MAX1272 EV Kit Schematic) and refer to the MAX1272
data sheet for timing requirements.
MAX1272 EV System
The MAX1272EVC16 operates from a user-supplied +8V
to +20V DC power supply. Windows 98-/2000-/XP-com-
patible software interfaces to the EV system board
through the PC’s standard serial port (virtual COM port).
See the
Quick Start
section for setup and operating
instructions.
2
_______________________________________________________________________________________
MAX1272 Evaluation Kit/Evaluation System
Evaluate: MAX1272/MAX1273
Figure 1. MAX1272 Evaluation Software Main Window
Detailed Description
of Software
The evaluation software’s main window is shown in
Figure 1. It controls the serial clock speed and sample
rate. It also displays the voltage and output code as
well as some statistics relating to the input signal. A
separate graph shows the data changing in real time.
The update rate is limited to about 10 samples per sec-
ond, due to COM port (virtual COM port) bandwidth
limitations.
Part Selection
The
Choose Part
pulldown menu allows the user to
evaluate the MAX1272CPA or the MAX1273CPA. The
default part is the MAX1272CPA.
Control Byte Pulldown Menus
The pulldown menus at the top of the main program win-
dow allow the user to select the control byte. The first
field represents the start bit and is always one. The sec-
ond field controls the input range and polarity. The third
field sets the power-down mode. The fourth field sets the
external clock. The last field selects either the internal or
an external reference.
Sample Rate
The SPI™ SCLK frequency area allows the user to vary
the analog-to-digital converter (ADC)-to-µC sample
rate. The PC is not capable of retrieving the data that
SPI is a trademark of Motorola, Inc.
was stored in the memory of the µC as fast as the µC
can obtain the data from the ADC, because the µC’s
SPI interface is much faster than the PC’s standard ser-
ial port. Hence, the ADC-to-µC sample rate refers to the
sample rate at which data is being sampled by the
ADC and stored in the µC’s memory. Use the pulldown
menu to select the desired SCLK frequency. The first
two digits are the divisors for the µC’s internal clock.
The next floating point number is the corresponding
SCLK frequency. The ADC-to-µC sample rate is dis-
played in the ADC-to-µC sample rate field located on
the right side of the main window.
The other sample rate of interest is the rate at which data
is being sampled from the µC’s memory to the PC. This
µC-to-PC sample rate is controlled using the field in the
lower right hand corner of the main window and can be
controlled in two different ways. Pressing the
Read
button
allows the user to manually obtain a sample from the µC’s
memory. Checking the
Read Every
checkbox allows the
user to automatically read samples from the µC’s memory
at a rate selectable in milliseconds.
To retrieve a block of consecutively sampled data to
the PC, click on the
Sample
menu located at the top
left-hand corner of the main window. The data block
length is selectable and the data can be saved to a file.
_______________________________________________________________________________________
3
MAX1272 Evaluation Kit/Evaluation System
Evaluate: MAX1272/MAX1273
TP1
J1-1
VDD
3
C1
1µF
C2
0.1µF
U1
AIN
5
1
2
3
4
5
VDD
V
DD
CS
SCLK
DIN
DOUT
6
J1-2
J1-3
J1-38
J1-37
J1-36
J1-35
VDD
REF
6
C3
1µF
2
1
J1-7
J1-8
TB0
J1-4
7
1
2
8
AIN
MAX1272
GND
GND
4
Figure 2. MAX1272 EV Kit Schematic
Statistics
The Minimum and Maximum fields in the statistics area
show the highest and lowest readings acquired. The
Average field shows a running mean. When reading
data manually by pressing the
Read
button, the
Average and RMS fields require approximately five
samples until they are accurately represented. The
Clear Statistics
button resets the statistics. To remove
offset errors, first apply 0V to the active input channel,
press the
Clear Statistics
button, acquire some sam-
ples, and then check the
Null Offset
checkbox. Once
checked, the label next to the
Null Offset
checkbox
shows the sampled offset error. This value is subtracted
from all subsequent measurements until the checkbox
is unchecked.
Detailed Description
of Hardware
The MAX1272 is a 12-bit, multirange, serial ADC. When
the MAX1272EVKIT board is connected to the
68HC16MODULE-DIP module, power is provided by the
module. See Figure 2 (MAX1272 EV Kit Schematic).
The MAX1272 has a software-selectable internal
+4.096V reference. The terminal block (TB0) on the
MAX1272EVKIT board is for applications requiring an
external reference.
Evaluating the MAX1273
The MAX1272EVKIT board can also be used to evalu-
ate the MAX1273. The MAX1272 and the MAX1273 dif-
fer only in analog input voltage range. The MAX1272
has a software-selectable input voltage range of 0 to
+5V, 0 to +10V, ±5V and ±10V. The MAX1273 has a
software-selectable input voltage range of 0 to V
REF
/ 2,
0 to V
REF
, ±V
REF
/ 2, and ±V
REF
. Simply replace the
MAX1272CPA with the MAX1273CPA.
Reference Voltage
The evaluation software assumes a +4.096V reference
voltage, unless otherwise specified. To override the
+4.096V reference value, apply the new reference volt-
age at the terminal block (TB0) on the board, type in
the new reference voltage (without the volt unit), and
press the
Set V
ref
button.
4
_______________________________________________________________________________________
MAX1272 Evaluation Kit/Evaluation System
Evaluate: MAX1272/MAX1273
Figure 3. MAX1272 EV Kit Component Placement Guide—
Component Side
Figure 4. MAX1272 EV Kit PCB Layout—Component Side
Figure 5. MAX1272 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
© 2006 Maxim Integrated Products
is a registered trademark of Maxim Integrated Products, Inc.
ARM技术
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
