MAX186EVKIT-DIP Maxim Integrated, MAX186EVKIT-DIP Datasheet - Page 5

• Manufacturer Part Number: MAX186EVKIT-DIP
• Description: Data Conversion IC Development Tools Programmers, Development Systems
• Manufacturer: Maxim Integrated
• Series: MAX186, MAX188r

Specifications of MAX186EVKIT-DIP

• Interface Type: 4-Wire (SPI, Microwire, QSPI, TMS320)
• Factory Pack Quantity: 1

The MAX186 software assumes a reference voltage of
4.096V. This value is used for calculating the displayed
results after each conversion. The value can be altered
to reflect the exact reference voltage of the MAX186 or
to scale the displayed readings. Changing the indicated
value does not alter the MAX186’s reference voltage.
The MAX186’s internal 4.096V reference voltage can be
adjusted over a ±1.5% range by adding resistors R10
through R13, shown on the schematic. Refer to the
MAX186 data sheet for detailed information about the
reference voltage.
The evaluation software’s main window controls the
active control word bits, serial clock speed, and sam-
ple rate. It displays the voltage and output code for
each active channel, as well as some statistics of the
input signal. A separate graph window shows the data
changing in real time. The update rate is limited to
about 10 samples per second due to COM port band-
width limitations.
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.
The Minimum and Maximum fields show the highest and
lowest readings acquired. The Average field shows a run-
ning mean based on the equation a
(a
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.
Choose the desired sampling rate (QSPI Clock), sam-
pling size (Sample! menu item), click Begin Sampling!
(in Sample! pop-up window). Sample size is restricted
to a power of 2 to permit FFT processing once the data
is saved to a file. After the samples have been collect-
ed, the data is automatically uploaded to the host and
is graphed. Once displayed, the data can optionally be
saved to a file.
i
-
1
). The Clear button resets the statistics. To remove
MAX186 Evaluation System/Evaluation Kit
Description of Software
_______________________________________________________________________________________
Reference Adjustment
i
= (k)(x
Statistics
Sampling
Controls
i
) + (1 - k)
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.
To scan through all channels, select SCAN from the
INPUT menu.
The evaluation software assumes a 4.096V reference
voltage, unless otherwise specified. Refer to the
MAX186 IC data sheet for more information. To override
this value, type the new reference voltage into the Vref
edit box and click the Set Vref button.
The 186RAM.MAX program is an 80C32 program that is
transferred from disk to the static RAM on the 80C32
module. It receives conversion commands from the
186EVKIT program running on the personal computer,
controls the conversion cycle, and returns the results. Its
operation is transparent to the user.
In addition to the two programs supplied with the
MAX186 EV kit, a small 80C32 bootstrap program is
stored in the EPROM located on the 80C32 board. The
EPROM resident program initializes the 80C32, estab-
lishes communications over the RS-232 link, checks the
static RAM, and downloads the 186RAM program. Its
operation starts on power-up and whenever the reset
button is pressed. It transmits an identification banner
after receiving the first character and then tests the on-
board static RAM.
The last operation performed by the EPROM resident
program is downloading the 186RAM program and
storing it in the static RAM. Once the program is fully
loaded, control of the 80C32 is transferred to the RAM
resident 186RAM program.
EPROM Resident Program
RAM Resident Program
Scanning All Channels
Saving Graphs to Disk
Reference Voltage
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