1
ISL26104AV28EV1Z Evaluation Board User Guide
General Description
The ISL26104AV28EV1ZA provides a means to evaluate the
functionality and performance of the ISL26104 A/D converter.
The board includes an AT90USB162 microcontroller with a
USB interface. The microcontroller interfaces to the ISL26104
ADC via a galvanically-isolated interface and provides serial
communication via USB between the board and the PC.
Software for the PC provides a GUI (graphical user interface)
that allows the user to configure the ISL26104 device and to
perform data capture, and to then process and plot the results
in the time domain, as a histogram, and/or to perform
frequency domain analysis on the captured data. The GUI also
enables the user to save conversion data from the ADC to a
file, or to save the results of the analyzed conversion data.
Key Features
• ADC is galvanically-isolated from USB connection
• On-board microcontroller
• On-board voltage reference
• Evaluation software
- Time domain analysis
- Noise histogram analysis
- FFT analysis
Ordering Information
PART
NUMBER
PACKAGE
(Pb-free)
ISL26104AV28EV1Z Evaluation Board
FIGURE 1. EVALUATION BOARD FOR THE ISL26104
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
Copyright Intersil Americas Inc. 2012. All Rights Reserved.
1-888-INTERSIL or 1-888-468-3774 |Intersil (and design) is a trademark owned by Intersil Corporation or one of its subsidiaries.
All other trademarks mentioned are the property of their respective owners.
December 18, 2012
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Hardware
The ISL26104AV28EV1Z evaluation board provides the user a
means of evaluating the ISL26104 Analog-to-Digital Converter
(ADC). The ISL26104 is a high performance 24-bit ADC that
includes a very low noise programmable gain amplifier. The
ISL26104 offers multiple gain selections: 1x, 2x, 4x, 8x, 16x, 32x,
64x and 128x. It offers 20 word rate selections from 2.5Sps to
4000Sps (clock = 4.9152 MHz). Gain and word rate selections
are made by writing into on-chip registers.
The board comes with an ISL26104 soldered in place. This can
be removed and an ISL26102 soldered in its place if desired.
Evaluation Board Overview
The ISL26104AV28EV1ZA evaluation board is segmented into
two sections. These sections are galvanically-isolated with a
multi-channel isolation chip. The two different sections of the
board can be readily identified in Figure 1, which shows an image
of the board. The ISL26104 ADC and its associated circuitry
(voltage reference and input signal components) are on the left
side of the image. The ADC and its associated circuitry are
powered by a laboratory supply. The microcontroller with its USB
interface is on the right side of the image in Figure 1. This
circuitry is powered from the USB connection. See Figure 2 for a
block diagram of the circuitry. The microcontroller provides the
USB interface to the PC. A software GUI is available to
communicate with the microcontroller and provides the means
to collect and analyze data from the ADC.
FIGURE 2. BLOCK DIAGRAM OF THE EVALUATION BOARD FOR THE ISL26104
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Galvanic Isolation
Galvanic isolation is not necessary in every application. The
purpose of the isolation on the evaluation board is to prevent
noise from the USB ground connection from affecting the
sensitive measurements made by the ADC when used in the 64X
or 128X gain settings. The ground connection of the USB cable in
most computers is referenced directly to the power supply
ground of the computer. This ground can be especially noisy in
notebook PCs powered from an external power module.
Operating the ADC on a power system that is galvanically
isolated from the USB ground ensures that the performance of
the ADC on the evaluation board will not be affected by ground
noise from the PC being used to collect data from the board.
ADC Section
The ADC section of the evaluation board has three banana jack
power connections that enable this portion of the board to be
powered from a low noise laboratory supply. The banana jack
labeled AGND serves as the power supply ground connection for
the ADC segment of the board. The DVDD jack supplies the
digital portion of the ADC (3.3V to 5V) and the section of the
galvanic isolation chip that interfaces to the ADC. The AVDD jack
supplies the analog portion of the ADC and the voltage reference.
The voltage reference used in the ADC circuitry is an Intersil
ISL21009BFZ25 2.5V reference. A header is provided to also
allow the use of an external voltage reference for the ADC. The
ADC portion of the circuitry on the board is illustrated in Figure 3.
The ISL26104 offers several sample rate, gain, and input
channel options. These options are selected using on-chip
registers that can be written by the PC GUI software. When a
command to change the gain, the rate, or the multiplexer
channel is issued by the GUI, the command is sent over the USB
connection to the microcontroller on the evaluation board. The
microcontroller then writes into the proper ADC register via the
serial port using the CS/, SDI, SDO/RDY and SCLK signals which
are connected to the ADC from the µC through the isolation chip
as shown in Figure 4.
FIGURE 3. ISL26104 ANALOG-TO-DIGITAL CONVERTER
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FIGURE 4. GALVANIC ISOLATOR CHIP
SDI
SCLK
CS
SDO/RDY
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The ADC uses a 4.9152MHz crystal operating with an on-chip
amplifier for its clock source. This can be disconnected and an
external clock can be sourced to drive the clock input to the chip.
Alternately, the XTALIN/CLOCK pin can be grounded and the ADC
will operate from an on-chip RC type oscillator.
The board provides a 2.5V reference IC as the voltage reference
for the ADC, as shown in Figure 5 or, an external voltage can be
connected to input terminals on the board (VREF+ and VREF-)
and selected through jumpers on headers J25 and J26 to provide
a reference voltage for the ADC as shown in Figure 6. These
headers also provide the option of selecting AVDD and AGND as
inputs to the VREF+ and VREF- on the ADC.
FIGURE 5. 2.5V REFERENCE
FIGURE 6. VOLTAGE REFERENCE SELECTION OPTIONS
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The evaluation board provides separate terminal connections for
each of the differential signals into the ADC. These terminals are
in shown in Figure 7. Be attentive of the labeling of the
connections and their polarities when connecting external
signals. The channel numbers on the terminal blocks are not in
numeric order and some have their polarities labeled opposite of
others.
FIGURE 7. ANALOG INPUTS
FIGURE 8. COMMON MODE SELECTIONS
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Header connector J17 in Figure 8 allows the user to select one of
the following options for the common mode bias (CMB) voltage:
the 2.5V voltage reference output, ground (AGND), a voltage
generated by a resistor divider (RDIV) that divides the AVDD
supply using two 1kΩ resistors, or a voltage determined by the
user which must be connected to the hole next to the header
connection labeled FLT (Floating Input). The voltage source which
is selected by header J17 is provided to the analog input
channels as a common mode bias voltage (CMB).
Each of the input channels has jumpers (for example, J9 and J10
for input AIN1 in Figure 7) to allow the user to connect the
common mode bias (CMB) voltage to either the AIN+ or the AIN-
input of the channel. This enables the external signal source to
be biased to a common mode value supplied by the board. If
both jumpers are put in place, and the analog inputs to the
terminals are left disconnected, the inputs to this particular AIN
channel of the ADC will be shorted to the common mode voltage.
This provides a means for testing the noise performance of the
ADC with both of its inputs (AIN+ and AIN-) shorted to a common
mode voltage.
The ADC interfaces to the microcontroller through the galvanic
isolators. The ADC side of the isolator chip is powered by the
same supply that powers the DVDD supply of the ADC.
The Microcontroller Section
Figure 9 illustrates the microcontroller circuitry. There is a reset
button provided but it is seldom necessary to use it. The
microcontroller has its own power-on reset which will initialize
the microcontroller when the USB interface is connected to a
powered PC. Power for the microcontroller section comes from
the USB interface. The microcontroller circuit includes a DIP
switch, some LEDs and two header connectors.
The board is shipped from the factory with the four switches of
the DIP switch set to the OFF position. This is required for normal
operation. Other switch positions are used at the factory to
troubleshoot the isolator interface if the board is not functioning
properly. These switch positions are not useful for normal board
application, therefore all the switches should be kept in the OFF
position.
The three LEDs will illuminate when the USB interface is plugged
in and actively powered. Some of the LEDs blink when the
microcontroller is passing a command to the ADC or when data
is being collected from the ADC.
The microcontroller section includes two headers. Header J1 is a
six pin connection used to program the flash in the
microcontroller. Header J22 provides access to the four signals
that are used by the microcontroller to interface to the ADC. If
desired, the customer could remove the isolator chip from the
board and use header J22 to connect into his own circuitry to his
ADC. This enables the customer to use the PC GUI software to
evaluate the ADC in the customer's system. An alternate method
of connection is to remove the ISL26104 device from the board
and connect into the customer circuit via the signals on header
J20. If this method is chosen, the customer would need to power
the ADC side of the isolator chip from his system (3V to 5V).
The microcontroller communicates with the ADC via the galvanic
isolator chip. The microcontroller side of the isolator is powered
by the voltage from the USB connection.
FIGURE 9. MICROCONTROLLER WITH USB INTERFACE
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Note on Power Supply Sequencing
There are two galvanically isolated sections to the board. The
ADC portion is powered by a laboratory supply. The
microcontroller section is powered by the USB connection.
Proper voltages from an external supply must be provided to the
DVDD (3.3V to 5V), AVDD (5V) and the AGND banana plug
connectors for the ADC portion of the board to function. LEDs, as
shown in Figure 3, will be illuminated by DVDD and AVDD when
they are powered. Note that these supplies, AVDD and DVDD, can
be applied and removed in any sequence without regard to each
other or with regard to whether the USB interface is connected
and powered or not. The USB interface can also be disconnected
and reconnected without consequence with regard to whether
the power supply to the ADC section of the board is powered or
not. In other words, there is no power supply sequencing
requirement for any of the supplies to the board, whether it be
from the laboratory supply powering the ADC section, or whether
it be the microcontroller section powered from the USB
connection.
Software
The evaluation board has GUI software available that runs on the
PC. The software is designed to operate under Windows XP or
later.
See “Appendix #1 How to Obtain and Install the GUI Software” on
page 19 to obtain the internet link to download the GUI software.
Once the PC GUI software is copied onto the PC, click on the
setup.exe file and follow the on screen instructions to load the
software. Note that the software uses the USB interface to
communicate with the evaluation board. The software uses the
USB HID driver that is part of the Windows operating system so it
is not necessary to load any other drivers for the USB interface.
Running the GUI
Before starting the GUI software the evaluation board should be
connected to the PC by means of a USB cable
With the board connected via USB, run the GUI program by
selecting Start ->All Programs->ISL261XX->ISL26XX Evaluation
Software.
If the software is started before the connection to the board is
made, the GUI will indicate that the USB interface is not
connected with the message: USB Status: Not Connected as
shown in Figure 10.
If this occurs, connect the evaluation board to the PC with the
USB cable. The USB status should change to Connected as shown
in Figure 11.
FIGURE 10.
FIGURE 11.
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The screen shows File, which is a pull down menu, and four
different window tabs, Configuration, Time Domain, Histogram,
and Frequency Domain. With the screen shown as in Figure 12,
the software has the Configuration window as the currently
active window. The first step of configuration is to select the
appropriate part number that represents the evaluation board to
be tested using the Device Selection window.
Associated with the Device Selection window is a pull down
menu with various part numbers as shown in Figure 12. The
ISL26104 option should be selected and the Initialize button
clicked to configure the GUI software to operate with this
particular evaluation board.
Before the Initialize button is clicked, the ADC section of the
board should be powered by the laboratory power supply if the
GUI software is to communicate properly with the ISL26104.
Once the Initialize button is clicked with the ISL26104 selection,
the screen will change and illustrate a block diagram of the
ISL26104 ADC with windows inside the block diagram to select
various options, such as the Input Mux channel and the Gain
options available in the ADC as shown in Figure 13.
The ISL26104 device uses on-chip registers as the means for it to
be configured. The user of the GUI software can use the
Configuration window to set up the various options in the
ISL26104 device. Some of these options are (1) Input channel
(Input Mux) selection, (2) Sample Rate selection, and (3) Gain
selection. The ISL26104 allows the user to configure the various
settings for the ISL26104 via the Configuration window of the
GUI as shown in Figure 13. The Sample Rate can be set by using
the Sample Rate pull down menu as shown in Figure 14. Sample
rates from 2.5 to 4000 samples per second can be selected. The
Input Mux can be changed via a pull down menu as shown in
Figure 15. The Gain can be changed via a pull down menu as
shown in Figure 16. Any time a menu option is changed the Write
Values button should be clicked. This instructs the GUI software
to send a command to the chip to change the appropriate
on-chip register. Note that multiple items (Sample Rate, Input
Mux, Gain, etc.) can be changed and the Write Values button
need only be clicked once for all the selections to be sent to the
evaluation board.
FIGURE 12.
FIGURE 13.
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FIGURE 14.
FIGURE 15.
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Offset calibration can be performed by clicking the Offset
Calibration button. This issues a command for the ISL26104 to
execute its offset calibration operation. If offset calibration is
performed, the value of the on-chip offset registers will be
displayed in the O/S window in the lower left portion of the block
diagram of the chip shown in the Configuration window. Note
that there are three 8-bit offset registers (high, mid and low)
inside the ISL26104 which make up the entire 24-bit offset
value. The decimal value of this 24-bit word is what is displayed
in the O/S window as shown in Figure 17.
FIGURE 16.
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At the bottom of the configuration window, there is an SPI
Communications window as depicted in Figure 18.
After writing Hex values into the Address text box and into the
Data text box the user can then click the SPI WR button to write
an 8-bit value into the on-chip register associated with that
address. Or, if the Data text window is empty and a Hex value is
entered into the Address window, the SPI RD button can be
clicked. This will cause the 8-bit value of the selected register to
be read from the chip and written into the Data text window. For
example, if the user selects '128' in the Gain pull down menu
and then clicks the Write Values button, this will set the gain
register in the chip for a gain of 128X. One can then use the SPI
Comm feature to read the register back. Enter 17 [this is the
address to read the on-chip gain register] (do not enter the letter
h or H as the text window will automatically interpret what is
typed as a hex value) into the Address window and the click the
SPI RD button, the value '7' will be returned and displayed in the
Data window. Hex '7' indicates that the binary value in the
register was set to '00000111', gain = 128.
Signal Processing Windows
From the Configuration window one can see three other Window
selection options: Time Domain, Histogram, and Frequency
Domain. These window selection options are seen in Figure 19.
Each of these windows will be discussed in the following sections
in detail. All three allow the user to collect and process data from
the ADC on the evaluation board.
Time Domain Window
The Time Domain window allows the user to collect samples
from the ADC on the evaluation board and display them in the
time domain. The number of samples is initially defaulted to 64,
but can be set in a pull down window from 1 to 1048576 (220). If
a large number of samples is requested on an ADC with a slow
FIGURE 17.
FIGURE 18.
FIGURE 19.
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sample rate, one should be aware of the amount of time required
for data collection. When the Acquire button is clicked, the
samples will be collected and transferred to the PC. The main
graphing window can graph up to 256 samples. If more than
256 samples are collected, the time plot of the entire sample set
can be displayed by clicking on the Pop Out button. Figures 20
and 21 illustrate the capture of 4096 samples. The window in
Figure 20 displays only the first 256 samples. Figure 21
illustrates the results when the Pop Out button has been
selected.
Buttons at the top of the plot provide several user graph tool
functions as follows:
The button options shown in Figure 22 are also available in the
Histogram and Frequency Domain windows.
House: Zooms to the original zoom scale factor.
Left/Right: Goes back/forward 1 zoom command. So if you
zoom in twice and want to go back to the first zoom, you'd click
the left arrow.
Four Points: Moves the axes around.
Magnifying Glass: Zoom box.
Scaling Icon (Up/down/left/right): Changes the size of the plot in
the window. You can scale the graph as large as the border.
Check Box (customize): Allows customization of axis labels/plot
title as shown in the Figure 23.
Disk (Save): Saves the plot as an image. When selected, a
window will open that offers several image format options.
Once the data from the ADC has been captured, it can be saved
to a file. The histogram and the spectrum analysis can also be
saved. See “Appendix #2 Data File Formats” on page 19 for a
discussion of the formats of the saved files. Note that the raw
data (conversion words from the ADC) files can also be read back
into the GUI once saved. Or data collected from another source
can be read into the GUI software for analysis if the proper data
format is used. See “Appendix #2 Data File Formats” on page 19
for details.
FIGURE 20.
FIGURE 21.
FIGURE 22.
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The About selection will be discussed first.
When the GUI is first started it sends a command to the
evaluation board and tells the microcontroller to send back the
version number of the firmware code that is in the
microcontroller. If File => About is selected, the GUI will open a
window that indicates the version number of the microcontroller
firmware, and the GUI software version as shown in Figure 25.
Click the OK button to close the window.
The File =>Exit selection is a means to exit and close the GUI
program.
The File =>Save selection is meaningful only after data has been
collected using the functions on the Time Domain, Histogram, or
Frequency Domain windows. Figure 26 shows that the options
under the File => Save selection are Raw Data (text), Histogram
Data (text), Spectrum Data (text), All Data (Excel), and
Configuration. These options allow the user to save data to a file.
The file formats for each of the options are discussed in
“Appendix #2 Data File Formats” on page 19. Note that the Excel
format is for Excel 2003 and supports only 65k cells, which limits
the number of samples that can be saved in this format.
The File =>Load Data option allows the user to read back into the
GUI raw data (conversion words for the ADC) once saved or, data
collected from another source can be read into the GUI software
for analysis if the proper data format is used. See “Appendix #2
Data File Formats” on page 19 for more information.
The File =>Configuration option allows the user to save the
register configuration of the ADC that is being used to collect
data. See “Appendix #2 Data File Formats” on page 19 for an
example configuration file format.
FIGURE 25.
FIGURE 26.
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Histogram Window
If one clicks on the histogram window after collecting data using
the Time Domain window the histogram of the time domain data
will be plotted. Alternatively, the Histogram window provides the
user options to set the number of samples to be collected and to
acquire a new sample set based upon this selection. The Bin
Width window allows the user to set the number of converter
codes that are counted in one bin of the histogram. This number
is defaulted to "1".
When the histogram is plotted, the plot includes markers for the
mean value (red vertical line) and for one standard deviation
from the mean on each side (green dashed lines). Signal
statistics are listed in the plot itself and in the text boxes below
the graph as shown in Figure 27. The Pop Out button shows the
graph without the statistics listed.
FIGURE 27.
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Frequency Domain Window
If the user has collected data in either the Time Domain window
or the Histogram window, and then clicks on the Frequency
Domain menu option, the data will be processed with the FFT
algorithm and the resulting spectral information will be
displayed, as shown in Figure 28. The red lines mark harmonics.
If no signal is present, the software assumes the highest point in
the spectrum is the fundamental. If the log(freq) check box is
checked, the spectral plot will be graphed with the frequency axis
on a Log scale, as shown in Figure29. If the Grounded Input Test
check box is checked, and data is collected with the input of the
converter shorted, the GUI software will calculate the various
parameters such as SNR (signal to noise ratio) by computing the
ration of an artificial full scale sine wave to the total noise in the
bandwidth. The Grounded Input Test check box should only be
checked if there is no actual signal input into the converter (The
board provides a means to short both differential inputs to an
ADC channel to a common mode voltage for this test). Note that
if the Grounded Input Test check box is not checked, the software
will compute parameters such as SNR, by calculating the ratio of
the largest magnitude component in the spectrum (other than
the DC offset) to the noise.
FIGURE 28.
FIGURE 29.
FIGURE 30.
FIGURE 31.
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There are several different selectable options in the Frequency
Domain window. The number of samples can be set up to
1048576 (220) using a pull down menu as shown in Figure 30.
Note that the frequency domain software (FFT computation)
must have at least 1024 samples to compute a proper spectral
plot. The software allows a number of different window functions
to be used. The different windowing options can be selected in
the Windowing menu as shown in Figure 31. These are normally
used when testing is performed with a sine wave as the input
signal. This same software GUI supports other ADC platforms
(higher speed SAR ADCs) where these windowing options are
more commonly used.
Figure 32 illustrates the spectral plot of one data set of 4096
samples. For this data collection, the ADC had its gain set to 1X
and its sample rate set to 1000Sps.
The results of the FFT can be averaged by setting the Mode radio
button to Ave. and then using the window next to the Ave. button
to set the number of data sets to be averaged. When averaging is
performed, the output results of many FFTs are averaged and are
used to produce a spectral plot with a smoothed (averaged)
spectrum as shown in Figure 33.
Recall that the spectrum plot data can be saved by clicking on
the File=>Save=>Spectrum Data option at the top of the window.
FIGURE 32.
FIGURE 33.
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Appendix #1 How to Obtain and
Install the GUI Software
The following is the address for the ISL26104 product page on
the Intersil web site.
http://www.intersil.com/products/ISL26104
Go to this link and find the “Documents” tab. The PC GUI
software installer can be downloaded from this location. Note
that the software installer does have a license agreement that
will be presented when the software is loaded onto your PC.
Appendix #2 Data File Formats
The GUI software allows the user to save data from the time
domain (raw data), data from the histogram processing, and
data from the spectrum processing segments of the software. It
also allows raw data (time domain data) files to be read back
into the GUI if they have the proper header and format.
Raw Data
As an example, a time domain collection of only 8 samples has
been collected and saved to a file. The content of the file that is
saved has the following format:
ISL26104
10.0
24
8
‐214
‐226
‐241
‐234
‐219
‐213
‐224
‐224
The file has a header that consists of the part number
(ISL26104), the sample rate (10), the number of bits in the
conversion word (24), and the number of samples in the file (8).
The header is followed by the 8 conversions words in signed
decimal format.
Histogram Data
A data collection of 1024 data words was collected and the
histogram performed. The histogram data was then saved into a
file. The content of the file has the following format. The
histogram statistics are listed first, followed by the converter
codes and their respective histogram counts.
SignalStatistics
Min:23
Max:35
Range:13
Mean:29.356
StDv:1.976
Code Hits
21 0
22 0
23 1
24 2
25 8
26 58
27 103
28 179
29 229
30 164
31 129
32 89
33 34
34 21
35 7
36 0
Spectrum Data
A data set of 1024 points was collected at a sample rate of
100Sps. The FFT output will produce a spectrum plot with 512
Bins of magnitude data. Only the beginning and ending portion of
the data file has been reproduced here to save space. Note that
the Bins start at 0 frequency and increase to one half the sample
rate (50Hz). Note that the magnitude in dB is the magnitude of
the noise in dB below full scale rms but it is scaled based upon
magnitude/√BIN, not magnitude/√Hz.
Freq Magnitude(dB)
0.0 ‐127.490860112
0.09765625 ‐130.138393031
0.1953125 ‐139.550586747
0.29296875 ‐132.866111959
0.390625 ‐127.884217984
0.48828125 ‐126.538951953
0.5859375 ‐126.769048076
0.68359375 ‐131.31820625
0.78125 ‐149.352655015
0.87890625 ‐134.478247602
0.9765625 ‐139.032099632
1.07421875 ‐133.269604586
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
48.92578125 ‐144.77615475
49.0234375 ‐154.371891495
49.12109375 ‐142.708481612
49.21875 ‐138.531922503
49.31640625 ‐138.378824752
49.4140625 ‐142.563086329
49.51171875 ‐158.690364592
49.609375 ‐144.250894284
49.70703125 ‐142.996812327
49.8046875 ‐144.030316874
49.8046875 ‐144.707081022
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Excel Data Format
If the File=>Save=>Excel option is used, the Time Domain,
Histogram and Frequency Domain data will be saved into an
Excel file with each of the three data sets on a different sheets as
shown in Figure 34.
Note that the Excel format is for Excel 2003 and supports only
65k cells which limits the number of samples that can be saved
in this format.
Configuration Data
Load Data Function
The GUI allows raw (time domain) data to be loaded back into the
GUI. Alternately, the user might collect data in another system
and import the conversion word data into the GUI to perform
analysis. To be able to read the data the file must have the proper
header (as discussed previously in the “Raw Data” on page 19 of
this appendix).
The header must have a header with a part number (this can be
something other than a chip number), sample rate, number of
bits in the converter, and the number of samples, followed by the
data in decimal format. The largest value of any reading cannot
exceed one half 2(number of bits in the converter). For example, if
the number of bits in the converter is 12, then the largest reading
can be no greater than (212)/2 or 2048.
TABLE 1.
ISL26104
REG. NAME REG. ADDR REG VALUE (HEX)
Word Rate 0x85 0xb
Input Mux 0x87 0x0
Channel Ptr 0x88 0x0
PGA Gain 0x97 0x0
Delay Timer 0xc2 0x0
FIGURE 34.FIGURE 28.
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ISL26104>partnumber
100.0 >samplerate
24 >numberofbitsintheconverter
8>numberofdatasamplesinthefile
‐394 >conversiondatainsigneddecimalformat
‐361
‐405
‐411
‐397
‐416
‐423
‐416
Appendix #3 USB VID and PID
The VID (vendor ID) for Intersil = 09AA) and PID (product ID) = 201C
for the evaluation board can be found by examining the Windows
Systems Information under Components => USB. It will be listed as
a HID Compliant device with the VID and PID indicated as follows:
Appendix #4 Evaluation Board
Factory Jumper Settings
Figure 35 indicates the position of the header shunts when the
board is shipped from the factory.
Header J17 is connected with the 2.5V reference selected as the
common mode voltage.
Headers J9 and J10 are shorted with shunts to connect the
common mode voltage to the AIN1+ and AIN1- signals coming
from the terminal block connector. This effectively shorts both
inputs to Channel 1 on the ADC to the common mode voltage
and enables the ADC to be tested with a shorted input. One or
both of these jumpers must be removed if the ADC is to measure
a signal on this channel.
Headers J25 and J26: the 2.5V_VREF option is selected on J25.
The AGND option is selected on J26. These enable the 2.5V
voltage reference chip to be the voltage reference for the ADC.
DIP switch: Switches S2-1, S2-2, S2-3 and S2-4 must be
positioned in the off position. If the switches are positioned with
any switch in the closed (ON) position, the microcontroller will be
put into a factory test mode, or into a non-functional state. If the
microcontroller is in either of these states, it will not
communicate properly with the PC software GUI.
FIGURE 35.
Application Note 1800
22
Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without notice. Accordingly, the reader is
cautioned to verify that the Application Note or Technical Brief is current before proceeding.
For information regarding Intersil Corporation and its products, see www.intersil.com
AN1800.0
December 18, 2012
Appendix #5 Evaluation Board Layout and Component Placement
FIGURE 36.
FIGURE 37.
Application Note 1800
23 AN1800.0
December 18, 2012
ISL26104AV28EV1Z Schematics
FIGURE 38.
ISL26104A
V
ISL26104 E
V
SHEET TITLE
PART #
VREF+
VREF-
2.5V
GND
RVIV
AVDD
VREF+
2.5V
GND
GND
VREF-
AIN1+
AIN1-
AIN2+
AIN2-
AIN3+
AIN3-
AIN4+
AIN4-
1GND_OR_NC
2VIN
3DNC
4GND 5
TRIM
6
VOUT
7
DNC
8
DNC
U6
ISL21009BFB825
2.500V
C19
1uF
X7R C21
0.1uF
X7R
12
34
56
78
J17
HDR4X2
R19
1K
R20
1K
1
2
J24
C27
0.1uF
X7R
12
34
56
J25
HDR3X2
12
34
56
J26
HDR3X2
R12 10
R13 10
C29
47uF
NO-POP
1
2
J8
C2
4700pF
X7R
C3
0.01uF
X7R
C4
0.01uF
X7R
J9
HDR2X1
J10
HDR2X1
1
2
J11
C5
4700pF
X7R
C7
0.01uF
X7R
C9
0.01uF
X7R
J12
HDR2X1
J13
HDR2X1
1
2
J14
C14
4700pF
X7R
C15
0.01uF
X7R
C16
0.01uF
X7R
J15
HDR2X1
J16
HDR2X1
1
2
J2
C17
4700pF
X7R
C18
0.01uF
X7R
C1
0.01uF
X7R
J5
HDR2X1
J6
HDR2X1
FLT
AGND
AVDD
AGND
2.5V_VREF
CMB 2.5V_VREF
AGND
AGND
AVDD
AVDD
2.5V_VREF
AGND
VREF+
VREF-
AGND
AGND
AIN1+
AIN1-
CMB
AGND
AGND
AIN2-
AIN2+
CMB
AGND
AGND
AIN3+
AIN3-
CMB
AGND
AGND
AIN4-
AIN4+
CMB
AGND
Application Note 1800
24 AN1800.0
December 18, 2012
FIGURE 39.
ISL26104AV28EV1Z Schematics (Continued)
ISL26104
AVDD DVDD
AVDDAGNDDVDD
PWDN
CS
SDI
SCLK
1
DVDD
2DGND
3
XTALIN/CLOCK
4
XTALOUT
5DGND
6
DVDD
7DGND
8DGND
9CAP
10 CAP
11 AIN1+
12 AIN1-
13 AIN3+
14 AIN3-
15 AIN4-
16 AIN4+
17 AIN2-
18 AIN2+
19 VREF-
20 VREF+
21 AGND
22
AVDD
23
LSPS
24
CS
25
SDI
26
PWDN
27
SCLK
28
RDY
U1
ISL26104
C11
0.1uF
X7R
C12
0.1uF
X7R
C13
2700pF
X7R
R9
10K
J3
HDR2X1
1
VDD1
2
GND1
3
A1 4
A2 5
A3 6
A4
7
EN1/NC
8
GND1
9GND2
10 EN2/NC
11 B4
12 B3
13 B2
14 B1
15 GND2
16 VDD2
U2
SI8441BB
C6
0.1uF
X7R
C8
0.1uF
X7R
LSPS
12
34
56
78
J20
HDR4X2
D1
RED
R1
200
D2
RED
R2
200
Y1
4.9152 MHz
R3
NO-POP
J4
SMA
J19
J21
J23
C10
0.1uF
NO-POP
C28
0.10uF
POLY
R4 200
R36 1K
VREF+
VREF-
AIN1+
AIN1-
AIN2+
AIN2-
AIN3+
AIN3-
AIN4+
AIN4-
AGND
AVDD DVDD
AGND AGND
AGND
DVDD
AGND
AGND
DVDD
USB_5V
AGND DGND
MOSI
SCLK
CS
DGND
MISO
SDO/RDY
AGND
AGND
AGND
AGND
AGND AGND
DVDD AGND AVDD
Application Note 1800
25 AN1800.0
December 18, 2012
FIGURE 40.
ISL26104AV28EV1Z Schematics (Continued)
RESET
USB
SW4
SW3
SW2
SW1
1XTAL1
2XTAL2
3GND
4VCC 5
PC2(PCINT11)
6
PD0(OC.0B/INT0) 7
PD1(AIN0/INT1) 8
PD2(RXD1/AIN1/INT2) 9
PD3(TXD1/INT3) 10
PD4(INT5) 11
PD5(XCK/PCINT12) 12
PD6(RTS/INT6) 13
PD7(CTS/HWB/T0/INT7)
14
PB0(SS/PCINT0) 15
PB1(SCLK/PCINT1) 16
PB2(PDI/MOSI/PCINT2) 17
PB3(PDO/MISO/PCINT3) 18
PB4(T1/PCINT4) 19
PB5(PCINT5) 20
PB6(PCINT6) 21
PB7(PCINT7/OC.0A/OC.1C)
22
PC7(INT4/ICP1/CLKO) 23
PC6(OC.1A/PCINT8)
24 RESET
25
PC5(PCINT9/OC.1B) 26
PC4(PCINT10)
27 UCAP
28 UGND
29 D+/SCK
30 D-/SDATA
31 UVCC
32 AVCC
U3
AT90USB162-16AU
Y2
8.000MHz
C20
22pF
COG
C22
22pF
COG
PC2
PC4
PC5
PC6
PC7
PD3
PB0
PB7
PB6
PB5
1
2
3
45
6
7
8
S2
SW-DIP4
LED1 LED2 LED3
R6
200
R7
200
R8
200
1
PWR 2
D- 3
D+ 4
GND
5
CASE 6
CASE
J18
USB-B
R5 22
R10 22
FB1
C23
1UF
X7R
R11
47K
1
2
3
4
S1
12
34
56
78
J22
HDR4X2
12
34
56
J1
HDR3X2
C24
0.1uF
X7R
C25
0.1uF
X7R
C26
0.01uF
X7R
VBUS
DGNDDGNDDGND
CS
MISO
MOSI
SCLK DGND
USB_5V
DGND
DGND
USB_5V
USB_5V
RESET
USB_5V
DGND
MISO
RESET
SCLK
USB_5V
MOSI
DGND
DGND
USB_5V
DGND
SCLK
MOSI
MISO
CS
