General Description
The MAX1282 evaluation system (EV system) is a com-
plete four-channel data-acquisition system consisting of
a MAX1282 evaluation kit (EV kit) and a Maxim
68HC16MODULE-DIP microcontroller (C) module. The
MAX1282 is a high-speed, 12-bit data-acquisition sys-
tem. Windows
95/98 software provides a handy user
interface to exercise the MAX1282's features.
Order the complete EV system (MAX1282EVC16) for
comprehensive evaluation of the MAX1282 using a PC.
Order the EV kit (MAX1282EVKIT) if the 68HC16MOD-
ULE-DIP module has already been purchased with a
previous Maxim EV system, or for custom use in other
C-based systems.
Features
o Proven PC Board Layout
o Convenient On-Board Test Points
o Data-Logging Software
o Fully Assembled and Tested
Evaluates: MAX1282
MAX1282 Evaluation System
________________________________________________________________ Maxim Integrated Products
1
19-1688; Rev 0; 8/00
For free samples and the latest literature, visit www.maxim-ic.com or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
Ordering Information
PART
TEMP. RANGE
INTERFACE
MAX1282EVKIT
0
C to +70C
User supplied
MAX1282EVC16
0
C to +70C
Windows software
Note: MAX1282 software is designed for use with the complete
EV system, MAX1282EVC16 (includes 68HC16MODULE-DIP
module and MAX1282EVKIT). If the MAX1282 evaluation soft-
ware will not be used, the MAX1282EVKIT board can be pur-
chased by itself, without the C.
MAX1282EVC16 System
PART
QTY
DESCRIPTION
MAX1282EVKIT
1
MAX1282 EV kit
68HC16MODULE-DIP
1
68HC16
C module
MAX1282EVKIT
Component List
MAX1282EVKIT Files
FILE
DESCRIPTION
INSTALL.EXE
Installs the EV kit files on your computer
MAX1282.EXE
Application program
KIT1282.C16
Software loaded into 68HC16
C
Recommended Equipment
Maxim MAX1282EVC16 (contains MAX1282EVKIT
board and 68HC16MODULE-DIP)
A small DC power supply, such as a 12VDC 0.25A
plug-in transformer or a 9V battery
An IBM PC-compatible computer running Windows
95/98
A spare serial communications port, preferably a 9-
pin plug
A serial cable to connect the computer's serial port
to the 68HC16MODULE-DIP
Quick Start
1) Carefully connect the boards by aligning the 40-pin
header of the MAX1282 EV kit with the 40-pin con-
nector of the 68HC16MODULE-DIP module. Gently
press them together. The two boards should be
flush against one another.
DESIGNATION
QTY
DESCRIPTION
C1
-C4, C10
5
0.01
F ceramic capacitors
C9
1
4.7
F tantalum capacitor
C11, C13
2
0.1
F ceramic capacitors
C12, C14
2
10
F, 10V tantalum capacitors
J1
1
2x20 right-angle socket
JU1
1
2-pin header
JU2
1
3-pin header
R1
-R4
4
300
5% resistors
R9, R10
2
10
1% resistors
TP1
1
8-pin header
U1
1
Maxim MAX1282BCUE (16-pin
TSSOP)
None
1
PC board, MAX1282 EV kit
None
1
3-1/2in software disk, MAX1282
None
1
MAX1282 EV kit data sheet
None
1
MAX1282 data sheet
Windows 95/98 is a registered trademark of Microsoft Corp.
2) Ensure that JU1 is closed and JU2 is in the 1-2
position (Table 1).
3) Connect a 7VDC to 20VDC power source to the C
module at the terminal block located next to the
on/off switch, along the top edge of the C module.
Observe the polarity marked on the board.
4) Connect a cable from the computer's serial port to
the C module. If using a 9-pin serial port, use a
straight-through, 9-pin female-to-male cable. If the
only available serial port uses a 25-pin connector, a
standard 25-pin to 9-pin adapter will be required.
The EV kit software checks the modem status lines
(CTS, DSR, DCD) to confirm that the correct port
has been selected.
5) Install the MAX1282 EV kit software on your com-
puter by running the INSTALL.EXE program on the
floppy disk. The program files are copied and icons
are created for them in the Windows Start menu.
6) Start the MAX1282 program by opening its icon in
the Start menu.
7) The program will prompt you to connect the C
module and turn its power on. Slide SW1 to the ON
position. Select the correct serial port, and press
OK. The program will automatically download
KIT1282.C16 to the module.
8) Apply input signal between CH0 and COM.
Observe the readout on the screen.
Detailed Description
MAX1282 Stand-Alone EV Kit
The MAX1282EVKIT provides a proven PC board layout
to evaluate the MAX1282. It must be interfaced to
appropriate timing signals for proper operation.
Connect +5V to VDD, and connect ground return to
GND (Figure 1). Refer to the MAX1282 data sheet for
timing requirements.
MAX1282 EV System
The MAX1282EVC16 EV system operates from a user-
supplied 7VDC to 20VDC power supply. Windows
95/98 software running on an IBM PC interfaces to the
EV system board through the computer's serial commu-
nications port. See the Quick Start section for set-up
and operating instructions.
Description of Software
The evaluation software's main window controls the ser-
ial clock speed and sample rate. It displays the voltage
and output code, as well as some input signal statis-
tics. A separate graph window shows the data chang-
ing in real time. The update rate is limited to about 10
samples per second, due to COM port bandwidth limi-
tations.
Controls
The control word is divided into several fields. To
change the active control word, drop down the appro-
priate field's combo box and select the desired option.
If the QSPITM clock is set to STOP, then configuration
data will not be sent until the READ button is pressed.
Statistics
The Minimum and Maximum fields show the highest
and lowest readings acquired. The Average field shows
a running mean. The Clear button resets the statistics.
To remove offset errors, first apply 0V to the active
input channel, clear statistics, acquire some samples,
and then check Tare. This average offset voltage will
now be subtracted from all subsequent measurements.
Sampling
Choose the desired sampling rate (QSPI clock), sam-
pling size (Sample! menu item), and press Begin
Sampling! (in Sample! pop-up window). Sample size is
restricted to a power of two to permit FFT processing
once the data is saved to a file. After the samples have
been collected, the data is automatically uploaded to
the host and is graphed. Once displayed, the data can
optionally be saved to a file.
Saving Graphs to Disk
Data in the real-time graph and in sampled data graphs
may be saved to a file. Only the raw output codes are
saved, but voltages may be inferred, based on the ref-
erence voltage and the maximum code value.
Scanning All Channels Input Signal
To scan through all channels, select SCAN from the
Input menu.
Evaluates: MAX1282
MAX1282 Evaluation System
2
_______________________________________________________________________________________
Table 1. Jumper Functions
JUMPER
POSITION
FUNCTION
Closed*
COM tied to GND
JU1
Open
COM must be connected to
analog common
1-2*
Operate
JU2
2-3
Shutdown
*Default configuration
QSPI is a trademark of Motorola, Inc.
Evaluates: MAX1282
MAX1282 Evaluation System
_______________________________________________________________________________________
3
Evaluating Shutdown
The evaluation software configures the 68HC16's QSPI
submodule to continuously read data from the
MAX1282 into the 68HC16. The sample rate is con-
trolled by the QSPI clock. To evaluate power-saving
modes, these automatic updates must be stopped.
First, set the QSPI clock control to STOP. This reconfig-
ures the 68HC16's QSPI submodule to stop driving the
serial clock. Second, in the evaluation software's main
window, uncheck the Read Every...msec check-box.
Next, choose the desired software power-down control
word, and press the Read button to send the new con-
figuration to the MAX1282. If evaluating the hardware
shutdown, move jumper JU2 to the 2-3 position.
Reference Voltage
The evaluation software assumes a 2.5V reference volt-
age, unless otherwise specified. Refer to the MAX1282
data sheet for more information. To override this value,
type the new reference voltage into the V
REF
edit box
and press the Set V
REF
button. Note: This new V
REF
value is used only by the evaluation software and does
not physically change the reference voltage.
Detailed Hardware
Description
U1, the MAX1282, is a high-speed, multichannel, 12-bit
data-acquisition system. Resistors R1R4 and capaci-
tors C1C4 form single-pole, lowpass anti-aliasing fil-
ters with a nominal 3s time constant and a corner fre-
quency of approximately 50kHz. C9 and C10 bypass
the ADC's voltage reference and reference buffer.
When plugged into the 68HC16MODULE, the VDD cir-
cuit is powered by +5V. (See Figure 1 and refer to the
MAX1282 data sheet.)
Troubleshooting
Problem: No output measurement. System seems to
report zero voltage or fails to make a measurement.
Check the VDD supply voltage. Check the reference
voltage using a digital voltmeter (DVM). Use an oscillo-
scope to verify that the conversion-start signal is being
strobed. Verify that SHDN is being driven high.
Problem: Measurements are erratic, unstable; poor
accuracy.
Check the reference voltage using a DVM. Use an
oscilloscope to check for noise. When probing for
noise, keep the oscilloscope ground return lead as
short as possible, preferably less than 1/2in (10mm).
Evaluates: MAX1282
MAX1282 Evaluation System
4
_______________________________________________________________________________________
Figure 1. MAX1282 EV Kit Schematic
MAX1282
U1
1
16
V
DD1
2
CH0
15
V
DD2
3
CH1
14
SCLK
4
CH2
5
CH3
12
DIN
6
SSTRB
7
DOUT
8
9
GND
COM
REFADJ
REF
SHDN
CS
13
11
10
REFADJ
C10
0.01
F
C13
0.1
F
R10
10
1%
C14
10
F
10V
TP1-7
J1-8
VDD2
TP1-6
J1-37
TP1-4
J1-36
TP1-5
J1-31
J1-38
TP1-3
J1-29
TP1-2
J1-35
GND
TP1-1
J1-1
J1-2
J1-3
J1-4
R1
300
C1
0.01
F
CH0
R2
300
C2
0.01
F
CH1
R3
300
C3
0.01
F
CH2
R4
300
C4
0.01
F
CH3
COM
JU1
2
1
21
3
JU2
VDD1
SHDN
REF
C9
4.7
F
10V
J1-7
C11
0.1
F
R9
10
1%
C12
10
F
10V
VDD1
VDD1
Evaluates: MAX1282
MAX1282 Evaluation System
_______________________________________________________________________________________
5
Figure 2. MAX1282 EV Kit Component Placement Guide--
Component Side
Figure 3. MAX1282 EV Kit PC Board Layout--Component Side
Figure 4. MAX1282 EV Kit PC Board Layout--Solder Side
PDF 
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