Renesas ISL94202EVKIT1Z User manual

USER’S MANUAL
UG106
Rev.1.0
Apr 13, 2021
ISL94202EVKIT1Z
Evaluation Kit
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Apr 13, 2021
The ISL94202EVKIT1Z is a kit that facilitates testing of the
ISL94202 Li-ion battery pack monitor and control ICs. The
ISL94202 monitors cell voltage, current, and temperature. It
converts the cell voltages, pack current, and temperatures to
12-bit digital values, provides cell balance control, and
provides complete stand-alone battery pack operation.
Default stand-alone operation of the ISL94202 can be
overridden by an external microcontroller. The PC based
Graphical User Interface (GUI) includes functions to monitor
stand-alone operation and to demonstrate operation with an
external microcontroller.
Specifications
This board has been configured and optimized for the following
operating conditions:
• Configurable to 3 to 8 cells, default 3 cells
• Standard cell voltage range 2.699V to 4.250V
• OV/UV delay times 1 and 4 seconds respectively
• CB maximum delta voltage 0.501
• CB maximum/minimum voltage 4.032V and 3.100V
NOTE: Consult programming options for full listing of programmable
parameters and ranges.
Key Features
• Status LEDs monitor RGO, EOC, SD, and PSD conditions
• Jumper configuration single or split path applications
• Wakeup push button for “Exit Sleep” control
• FETs off push button for quick all FETs off condition
• Cell balance LEDs for MCB process observation
• PCB layout accommodates “solder braid” addition for high
current evaluation
• Software enables real time observation and data collection
of 14 analog measurements and 27 digital status indicators
Ordering Information
PART NUMBER DESCRIPTION
ISL94202EVKIT1Z Evaluation kit for the ISL94202
FIGURE 1. BASIC EVALUATION TEST SETUP BLOCK DIAGRAM
DC POWER
SUPPLY
-
+
MCB_PS_Z ISL94202EVAL1Z
ISL94203INTFACE2Z PC
USB 2.0
ISLI2CCABLE1Z
CABLE
ISL94202IRZ
P+
GND
CELL BALANCE CIRCUITS
TEMP
SENSE

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ISL94202EVKIT1Z
What is Inside
The evaluation kit contains:
• ISL94202EVAL1Z evaluation board
• MCB_PS_Z multicell power supply test board
• ISL94202INTFACEKIT1Z USB to I2C interface kit, includes a
PCB and I2C cable
• USB cable, connects PC to USB-I2C interface board
What is Needed
The following instruments will be needed to perform testing:
• 30V/1A adjustable power supply
• Wires to connect power supply to MCB_PS_Z board
• Precision multimeter (optional)
• Oscilloscope (optional)
• Cables and wires (optional)
Software Installation
Step 1: Connect the ISLUSBI2C USB to the PC. The board
should automatically enumerate in the device control
panel under Human Interface Devices. The vendor ID
will be 0x09AA and the product ID will be 0x2036.
Because it is a HID device, no special driver is needed.
Step 2: Copy the isl94203evkit1z-software.exe program to the
PC (any desired location). Double-click to run the
installation file. Note you may need to use the “Run as
Administrator” option when performing the
installation.file.
Quick Hardware Setup Guide
Step 1: Check the jumpers and switches on the board. The
board should be configured as follows:
• ADDR jumper set to “0”.
• xT2 Select jumper on either “CELL” or “FET”.
• FET jumpers set for either one path or two path.
Start with one path.
• J4 jumper is set to “1 Path”.
J9 jumper is set to “1 Path”.
Step 2: Connect the power supply to the MCB_PS_Z board. The
positive terminal is J5/J11 and the negative terminal is
J8/J12. There should be a jumper on JP2/8CELL.
Step 3: Set the power supply voltage to 28V (3.5V per cell).
(Optional: check that the voltages at terminal J1 or J3
are 3.5V per cell).
Step 4: Turn off the power to the power supply.
Step 5: Connect the ISL94202 board directly to the MCB_PS_Z
board at connector J1. Make sure the board is
connected on the ground side of J1 (see Figure 4).
Step 6: Turn on the power to the supply. If no LEDs light, press
the “WakeUp” button. Notice that there is one green
LED (RGO), indicating the LDO regulator on the
ISL94202 is operating.
The voltages at various points should be:
RGO = 2.5V ±3%
VREF = 1.80V ±0.5%
Step 7: Connect the USB port of the PC to the USB port of the
ISL94202INTFACEKIT1Z interface board.
Step 8: Connect the I2C cable from the
ISL94202INTFACEKIT1Z board to the
ISL94202EVKIT1Z board (J13).
Step 9: Open the ISL94202 GUI software. Use the software to
read the cell voltages.
Step 10: Compare the voltages at the board input (use a meter
to measure each input voltage, because the MCB_PS_Z
board may not accurately divide the voltages into equal
3.5V steps) with the readings provided by the GUI.
These voltages should closely match.
Step 11: See other operations described later in this document.
PCB Layout Guidelines
The AC performance of this circuit depends greatly on the care
taken in designing the PC board. The following are
recommendations to achieve optimum high performance from
your PC board.
• The use of low inductance components, such as chip resistors
and chip capacitors, is strongly recommended.
• Minimize signal trace lengths. This is especially true for the
VDD, charge pump decoupling, CS1, CS2, and VC0-VC8 inputs.
Trace inductance and capacitance can easily affect circuit
performance. Vias in the signal lines add inductance at high
frequency and should be avoided.
• Match channel-to-channel analog I/O trace lengths and layout
symmetry. This is especially true for the CS1 and CS2 lines,
since their inputs are normally very low voltage.
• Maximize use of AC decoupled PCB layers. All signal I/O lines
should be routed over continuous ground planes (i.e., no split
planes or PCB gaps under these lines). Avoid vias in the signal
I/O lines.
• When testing, use good quality connectors and cables,
matching cable types and keeping cable lengths to a
minimum.

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ISL94202EVKIT1Z
FIGURE 2. ISL94202EVAL1Z TOP OF BOARD
FIGURE 3. ISL94202EVAL1Z BOTTOM OF BOARD

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FIGURE 4. ISL94202EVKIT1Z BOARD SETUP
MCB_PS_Z BOARD
SET I2C ADDR
SET xT2 THERMISTOR
TO FET OR TO CELL
CELL BALANCE
LEDs
TO PC USB PORT
WAKE UP
CONTROL
TO USB-I2C
BOARD
I2C PORT
FETSOFF
MANUAL
CONTROL
ISL94202EVKIT1Z BOARD
I2C PORT TO
SETS CHMON
TO 1 PATH OR
2 PATH
6V TO 38V
SETS POWER PATH
(CHARGE/DISCHARGE)
1 PATH OR 2 PATH)

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Quick GUI Setup Guide
Step 1: Once the board is powered up and connected to the PC
through the USB cable, start the GUI program. Then
click on the dropdown box.
FIGURE 5. MAIN GUI START-UP WINDOW

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Step 2: Click on “Read Voltages (Single).” This updates all the
cell voltage, temperature and current readings, and
updates the status indicators.
Step 3: Click on “Read Pack Settings.” This returns the
configuration parameters set in the device.
Step 4: Review the operation of the GUI features in the
following sections.
FIGURE 6. MAIN GUI WINDOW SHOWING PACK SETTINGS

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Using the GUI
Common Screen
The right side of the GUI shows the status of the ISL94202. At the
top are voltage, current, and temperature readings. The bottom
are the status bits.
At the bottom of the screen are several controls for temperature
settings and memory access.
CELL VOLTAGE SCANS
The voltage readouts (Figure 7) show the values for each cell,
plus CELLMAX and CELLMIN values. The CELLMAX and CELLMIN
values are returned from the ISL94202 registers. To properly
implement this operation, the GUI stops the internal voltage scan
of the ISL94202 (using the µCSCAN bit). It then reads the cell
voltages and CELLMAX and CELLMIN values and restarts the
automatic scan of the device. The values are read
asynchronously, so without stopping the scan there is not
sufficient time to read all the values prior to the next internal
scan. For this reason the CELLMIN and CELLMAX values are often
reported from a different scan than the rest of the cell voltages.
Also, during the scan, the cell balance operation is stopped. So
that the cell balance currents do not cause false readings of the
cell voltages due to external voltage drops.
To the right of the cell voltages, there is a graphic indication of
the capacity of the cell that is based on the voltage of the cell. In
this graphic depiction, the scale shows no bar when the voltage is
less than or equal to the undervoltage threshold. It shows 100%,
or maximum, when the cell voltage is equal to or greater than the
overvoltage threshold. See the overvoltage and undervoltage
thresholds in the Pack Settings tab on the left of the screen.
The GUI highlights the specific cells that equal the CELLMAX and
CELLMIN voltages. This helps to identify which cells are high or
low on quick inspection.
When any cell voltage is lower than the undervoltage level, or
higher than the overvoltage level, the background color of that
voltage readout changes to red. When the voltage rises above the
UV recovery voltage or drops below the OV recovery voltage, the
background color returns to white. These color changes are GUI
representations of the cell voltage conditions, the actual
indication from the device is shown by the UV and OV status
indicators (bottom right of the screen). These indicators come
directly from the device status bits.
Below the CellMIN and CellMAX readings are three boxes that
show additional voltage values. The top box contains the sum of
the individual cell readings. The middle box shows the voltage
reading of the total battery pack as derived from an internal
divide by 16 voltage divider and converted by the ADC.
Comparing these two values allows a gross determination if
there is a cell voltage failure.
The bottom box shows the voltage of the 2.5V regulator. The
regulator voltage is internally divided by 2, then converted by the
ADC and multiplied by 2 prior to display.
Pressing the “Read Voltages (Single)” button completes one read
of the values in the device (see Figure 8). This includes all of the
voltages and the status bits. Between presses of this button, the
device continues to scan the voltage, current, and temperature
values at the rate of 32ms (or 256ms if in IDLE mode, or 512ms
if in DOZE mode).
Pressing the “Auto Scan START” button starts a repetitive update
of the values. The rate of update is set by the “Rate (sec)”
dropdown box. As shown, the GUI updates the voltages and
status every 1 second. Autoscan is stopped by pressing the
autoscan “STOP” button. While the autoscan is operating, all
other memory accesses are prohibited. To read the pack settings
or change a register value, first stop the automatic scan.
To log the data, press “Logging START” prior to clicking on the
“Auto Scan START” button. The data will be stored as a text
document in a file location specified by the user. When all data
has been captured, stop the auto scan and stop logging.
TEMPERATURE READINGS
To the right of the pack voltage values are the temperature
readings (see Figure 9). In the default state, these boxes report
the voltage on the temperature inputs. There are two boxes for
each temperature.
The internal temperature reading (at the top) has two boxes. The
left box shows the voltage reading from the internal temperature
sensor. This voltage is dependent on the setting of the
temperature gain bit (TGAIN). The temperature gain can be
FIGURE 7. VOLTAGE READOUTS
FIGURE 8. MEASURE OPTIONS
FIGURE 9. TEMPERATURE READINGS

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changed using the GUI by clicking the “TGAIN” button in the
temperature box in the bottom left of the screen (below the tabs).
The box on the right shows the conversion of the internal
temperature to °C. This conversion uses Equations 1 and 2:
For the external temperatures, the left box shows the digital
reading from the ADC. The right box shows the applied input
voltage. The value on the left is dependent on the setting of the
TGAIN bit. If TGAIN = 0, then the temperature input voltage is
multiplied by 2 prior to being read by the ADC. If TGAIN = 1, then
the temperature input voltage is multiplied by 1. The left box of
the external temperature readings simply translates the voltage
readout by the ADC. The right box calculates the input voltage,
based on the setting of the TGAIN bit.
The temperature readings can also be displayed in °C
(see Figure 10). The conversion to °C depends on several items.
First is the gain setting, so the actual input voltage is known.
Second is the external resistor divider components. Third is the
conversion of the thermistor value to °C.
The gain setting is important only for determining the voltage
applied at the input xTn pin.
Next, the conversion depends on the external resistor divider, and
assumes that the external circuit is implemented as shown in the
Thermistor tab drawing, Figure 11.
There is a 10k resistor parallel to the thermistor. There are two
reasons for this. First, it makes the conversion curve more linear.
Second, the thermistor voltage range better matches the default
2 times gain on the temperature input amplifier. The thermistors
are from Murata (XH103F). If an external thermistor replaces the
thermistors on the board, the conversion can be changed by
changing the values in the Thermistor tab of the GUI. The values
in the table are the voltages applied to the xTn input pins. The
voltage depends on the resistance of the Thermistor at each
temperature and the voltage on the TEMPCO pin. The TEMPCO
voltage is 2.5V.
Based on calculations, the voltage/temperature curve for this
circuit is shown in Figure 12 on page 9. The GUI uses the
Thermistor table for this conversion and performs a linear
interpolation between points.
For calculations of the external temperature, the Thermistor tab
contains a value for the external divider resistor. This can be
changed by the user, but not saved.
(EQ. 1)
TGAIN 0=intTemp mV
1.8527
---------------------------------------273.15–ICTemp C=
(EQ. 2)
TGAIN 1=intTemp mV
0.92635
---------------------------------------273.15–ICTemp C=
FIGURE 10. TEMPERATURE READINGS DISPLAYED IN °C
FIGURE 11. ISL94202 GUI THERMISTOR TAB

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CURRENT READINGS
The current readout consists of four boxes (see Figure 13). The
top box shows the voltage across the sense resistor, as reported
by the device and converted to volts. The next box shows the
current reading in milliamps. This value depends on the value of
the current resistor, which can be entered into the third current
box. The default value is 1Ω, because that is the value on the
ISL94202EVKIT1Z board. If the resistor value changes, then this
value can be changed in the GUI (but the default cannot be
changed in this revision of the GUI). The bottom box simply
relates the current amplifier gain setting in the device. In
automatic scans, there is an automatic gain control. The gain
setting is most useful when forcing a current read by the GUI.
STATUS BITS
The status indicators on the lower right of the GUI screen (see
Figure 14) reflect the status of the bits in the device. If an
indicator is red, it shows a fault or out-of-bounds condition. If an
indicator is green, it is showing an operating condition, such as
current direction or power mode.
The status indicators are automatically updated when doing a
voltage read operation. However, refreshing only the status bits is
much quicker. So, clicking the “Read Status bits” updates only
the status.
FET INDICATORS
Above the voltage readings are the FET indicators (see
Figure 15). These show the status of the PCFET, CFET, and DFET
control bits. If the bit is “1” indicating that the FET should be on,
the indicator is green. If the bit is “0” indicating that the FET
should be off, then the indicator is red.
The FET indicators are more than just readouts. Clicking on the
indicators can also set or clear the bits to turn on or turn off the
FETs. However, the GUI does not have control over the FETs when
the device is operating in stand-alone mode. Controlling the FETs
through the GUI requires that the µCFET bit is set first. This bit is
set or reset using the “µC Controls FET” button in the µC Control
Tab.
FIGURE 12. VOLTAGE TO TEMPERATURE CONVERSION
0.000
0.100
0.200
0.300
0.400
0.500
0.600
0.700
0.800
-50 0 50 100 150
TEMPERATURE (°C)
INPUT VOLTAGE (V)
FIGURE 13. CURRENT READOUT
FIGURE 14. STATUS INDICATORS
FIGURE 15. FET INDICATORS

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Above the FET control bits are some controls to change the
operation of the device. These controls are “PCFET enable”,
“CFET on during OV”, and “DFET on during UV”.
Setting the “PCFET enable” to active causes the PCFET to turn on,
instead of the CFET, when the voltage is below the Low V Charge
threshold voltage (see the Pack Settings tab).
Setting the “CFET on during OV” to active means that the charge
FET will turn on when there is an overvoltage condition, if the
device detects a discharge current. This reduces heat generated
in the CFET during discharge, which is more important when
there is a single charge/discharge path configuration.
Similarly, setting the DFET on during UV to active means that the
discharge FET will turn on when there is an undervoltage
condition, if the device detects a charge current. This reduces
heat generated in the DFET during charge, which is more
important when there is a single charge/discharge path
configuration.
OTHER MAIN SCREEN CONTROLS
Communication to the device requires an I2C bus. The I2C bus
uses a Slave byte to determine the specific device on bus that is
being addressed. In the GUI, this is set by the “I2C Addr” box
(see Figure 16), which is located in the lower left of the screen.
By default, the Slave Byte is 50H (0101 000x), which addresses
the device having the ADDR pin pulled low. In a cascade
configuration (or an application that does not need current sense
or FET control, where the ADDR pin is tied high,) write the I2C
Address as 52.
Temperature measurement options are selected in this box
(Figure 17) below the tabs. The pack settings and temperature
outputs can be shown as either volts or °C. Changing the setting
initiates a voltage scan and an update of the Pack Settings. The
calculations are made in the GUI as described in previous. The
device simply maintains the voltage value associated with the
temperature.
This box also has the selection for the TGAIN bit. Clicking on the
TGAIN box changes the TGAIN bit in the device, updates all of the
RAM settings for temperature limits and initiates an update of
the Pack Settings tab. It does not do a voltage scan. The caption
shows the current status of the temperature gain. Figure 17
indicates that the temperature gain is set to 2 times.
Access to EEPROM requires an access control bit to be set prior
to a read or write operation. In all of the screens where a button
initiates multiple read or write operations, the memory access is
automatically set to the correct access code and automatically
reverts to RAM access. However, for individual memory read or
write, it may be necessary to change the access code. These
buttons allow this access code change. Simply click on the
desired memory area button, prior to the actual read or write
operation.
The ISL94202 Internal AD Utility screen enables the user to view
and record AD readings in real time. By using the I2C interface,
the GUI enables a user to select any of the internal Mux channels
and view/capture the results in real time.
To bring up the AD form, click on the “Internal AD Utility”
selection on the menu bar of the main form.
When first loaded, the new form will appear as in Figure 20 on
page 11.
FIGURE 16. I2C ADDRESS BOX
FIGURE 17. TEMPERATURE MEASUREMENT OPTIONS
FIGURE 19. INTERNAL AD UTILITY LOCATION
FIGURE 18. MEMORY ACCESS

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An important first step is to select an internal Mux Channel that
is going to be measured. By making a selection (clicking on a
Mux selection button, see Figure 21), data collection/graphing
will automatically start and after a few seconds, “Auto Range”
will take place.
Essentially, clicking in the frame selection selects the value
written to register 0x85. The user can consult the datasheet for
specifics related to each Mux Input connection.
FIGURE 20. INTERNAL MUX AND AD FORM
FIGURE 21. MUX SELECTION BUTTONS

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A real-time display of the register contents is displayed in
Figure 23.
Therefore, this selection programs the “MUX” blocks connected
to the input of the internal AD.
FIGURE 22. REGISTER 0x85
FIGURE 23. REGISTER CONTENT
FIGURE 24. ANALOG MUX

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1. Actual Dual Byte Hex value of AD reading
2. Calculated value based on channel selected
3. Active channel being measured
4. GO Starts and STOP ends data collection. Click “Stop” to save
collected readings to file.
5. Enable Plot, speeds up data collection by disabling real-time
graphing
6. Highest reading – lowest reading
7. Display of most recent reading
8. Peak/Maximum value recorded
9. Minimum value recorded
10. Clears items 6, 8, 9
11. Resets graphing scale to max default
12. Recalculate Maximum and Minimum values of graphing area
13. Decreases volts per division (visual only does not affect
collected readings)
14. Increase voltages per division (visual only does not affect
collected readings)
15. Recenters midrange scale and moves graphing range
16. Actual time in milliseconds to capture and graph a
measurement
17. Hex value of Mux control register
18. Internal Mux selection
19. PGA gain selected when making a current measurement
20. Checking will append latest collection of readings to a file
21. Browse to directory location where captured readings will be
saved
22. Perform actual write operation
The Internal AD Utility form is a separated form that can be
closed or minimized independent of the main screen
(see Figure 26 on page 14).
MAIN AD FORM TOOLS
FIGURE 25. MEASUREMENT SCREEN
123
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20 21
22

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FIGURE 26. INTERNAL AD UTILITY
To quit the program, click on “Quit”.

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Tab Controls
ISL94202 Memory Access
RAM
The ISL94202 has two main memory areas, RAM and
Configuration Memory. The RAM area contains the transient
values, such as cell voltages, status bits, and microcontroller
override conditions. The RAM registers relate to the part of the
GUI already described, and the GUI reads and writes these
registers as needed. The user also has direct access to the RAM
memory through the RAM tab. See Figure 27.
To update the values in the GUI with the values in the ISL94202,
press the “Read All RAM” button. The display now shows the hex
values of the RAM registers. Alternatively, each individual
location can be updated by clicking on the “R” to the right of the
register location.
There are only six registers that can be changed by the user.
These are addresses 84H to 89H. These locations have a “W”
next to the register. To change the register contents, write a new
hex value in the desired location and press the “W” button (or the
“Write All RAM” button). Until a write occurs, the contents of the
ISL94202 RAM are not changed.
As shown in Figure 27, hovering the mouse pointer over the
address of a register returns a description of the register. Also,
the registers are color coded to match the datasheet and to
group like registers. For example, in Figure 27, registers 80H to
84H are cyan color. These are the status registers. Also, registers
8EH through ABH are blue. These registers hold the voltage
readings for the cells, current, and temperature.
When pressing the “Read All RAM” or “Write All RAM” buttons,
the color of the button changes and the caption changes to
“Busy”. During this time the GUI is performing the specified
operation and other operations are prohibited until the read or
write completes and the color and caption return to normal. This
sequence occurs on all controls.
The main screen shows the “real world” contents of the
ISL94202 registers, converting hex values to volts, current, or
temperature and indicating individual status bits. The GUI
performs this update when the “Read Voltages (Single)” or
automatic scan executes. The update operation begins with a
Read All RAM operation. This brings in values from the ISL94202
(see Figure 28 on page 16). The GUI then converts the hex values
in RAM to the proper voltage, current, or temperature value.
The GUI controls for the writable RAM registers are located in the
µC Control tab. These tab operations will be discussed in more
detail in the following sections.
FIGURE 27. ISL94202 GUI RAM ACCESS TAB

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FIGURE 28. ISL94202 GUI RAM UPDATE OPERATION (READ OPERATION NUMBERED)
ISL94202
RAM MEMORY
ISL94202
GUI RAM TAB
ISL94202
MAIN SCREEN
2
3
1
NOTE: “Read Voltages (Single)” or “Read Status Bits” operation execution steps are numbered. “Write All RAM” writes to the ISL94202 RAM memory,
then updates the Main Screen.

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CONFIGURATION MEMORY
The Configuration Memory consists of two parts, the EEPROM
cells and Configuration RAM. On power-up, the contents of the
EEPROM is copied to the Configuration RAM. The device operates
out of Configuration RAM.
Reading and writing the EEPROM does not automatically go
through the Configuration RAM. Writes made to the EEPROM
locations will go into effect when the device power cycles or
when the EEPROM contents are read from the EEPROM and
rewritten to the Configuration RAM.
In the normal course of developing an application, a change is
made to the Configuration RAM, which changes the operation of
the device. For example, changing the overvoltage setting in the
Configuration RAM changes the voltage at which the device
detects a fault condition. However, the value has not yet changed
in the EEPROM, so a power cycle returns the old OV threshold. To
make the value permanent requires that the value also be
written to the EEPROM.
The EEPROM tab (see Figure 29) of the GUI shows only one set of
registers. This could be the values read from the Configuration
RAM or from the EEPROM. Which values it displays is dependent
on the access code. The access code is set in Register 89H, but
the GUI automatically sets this bit when the “Read EEPROM” or
“Write EEPROM” buttons are pressed. The Access code is also
settable by clicking the Memory Access button as described
previously.
To write to individual bytes of the RAM part of the Configuration
Memory, set the “RAM Access” in the Memory access box. Each
byte in RAM can be written separately.
Writing to individual bytes to the EEPROM part of the
Configuration Memory is limited. Each EEPROM write needs to
write all four bytes on a page. For this reason, the GUI has a
different (larger) button for writing to EEPROM. As previously
mentioned, in order to write to a page of EEPROM, it is necessary
to set the “EEPROM Access” in the Memory access box prior to
the write.
As with the RAM tab, hovering over an address box brings up a
dialog showing a simple description of the register contents.
Also, the various registers are color coded as shown in the
datasheet and are grouped by function.
The EEPROM tab has three other buttons. The first is a “Load
Factory Default” button, which fills the GUI EEPROM locations
with the factory default values (as defined at the time of the GUI
release) and lets the user recover to a known good operating
point. Again, use of this button simply fills the GUI registers. To
change the operation of the device or the contents of the
EEPROM requires a separate write for each memory location.
The other two buttons are “Save User Default to File” and “Load
User Default from File.” These commands allow the user
Configuration Memory to be saved and recalled. The values
saved are locations 0H through 4BH.
FIGURE 29. ISL94202 GUI - EEPROM ACCESS TAB

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USER MEMORY
The user memory area is different from the Configuration
memory. The user memory does not have a RAM component, so
all reads and writes are to the EEPROM only. Also, the device
ships with the user memory cleared. So, an initial read from user
memory reads 0.
Using the Load User Factory Default tells the GUI to put the
software revision number in the GUI locations for the user
memory. The user can keep these values or load other data in
the GUI boxes. To write the data to the ISL94202 User EEPROM
requires individual writes (click the “EEPROM Memory Access”
first) or a write all, using the “Write User EE” button (this
automatically sets the EEPROM Access bit).
The User EE tab also includes a Load Default from File and a
Save User Default to File. These buttons load and save User EE
data at addresses 50H to 57H only.
FIGURE 30. ISL94202 GUI - USER EEPROM TAB

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ISL94202EVKIT1Z
PACK SETTINGS TAB
The Pack Settings tab (see Figure 31) provides access to the
contents of the Configuration RAM, but with “real world” values.
This provides an easier way to program the operation of the pack
and to monitor the present settings. Values in the Pack Settings
tab are saved in the GUI. When a “Read Pack Settings” button is
pressed, the value is read from the device and loaded into the
Configuration RAM tab of the GUI. The GUI then takes the
contents of the Configuration RAM, calculates the real world
value, and writes it to the Pack Settings tab.
When a value is changed in the Pack Settings tab, nothing
happens until a “Write Pack Settings” button is pressed. The GUI
then takes the value in the Pack Settings tab, converts the value
to hex, and writes the new value to the Configuration RAM tab in
the GUI. These values are then written from the GUI to the RAM
part of the device Configuration memory. If a value is changed in
the GUI, but no write button is pressed, then the device is not
updated with the new value.
As soon as the Write Pack operation completes, the ISL94202
begins operating with the new parameters.
The Pack Settings tab also includes a “Write EEPROM” button.
This is a convenience, since it does the same function as the
button in the EEPROM Tab. However, in the Pack Settings tab, it
is necessary to do a “Write Pack Settings” operation prior to
doing the “Write EEPROM”. Otherwise, the EEPROM would not
get the latest values from the Configuration Memory RAM to
write to EEPROM. This is because the “Write EEPROM” writes
values from the GUI Config Mem tab to the device and the values
in the GUI Config Mem tab are not updated until execution of the
“Write Pack Settings” operation.
Figure 32 on page 20 shows a graphical representation of the
operation of the Pack Settings tab operation, the GUI EEPROM
tab and the ISL94202 internal registers.
The memory operations of the Pack Settings tab was previously
described. The next section covers some additional details about
the calculations and use of the values shown in the Pack Settings
tab.
FIGURE 31. ISL94202 GUI - PACK SETTINGS TAB

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ISL94202EVKIT1Z
FIGURE 32. ISL94202 GUI PACK SETTINGS TAB MEMORY OPERATIONS
(NO USER
SHADOW
RAM)
COPY
COPY
COPY
ISL94202 DEVICE
CONFIGURATION RAM
ISL94202 DEVICE
EEPROM MEMORY
(EEPROM SHADOW MEMORY)
ISL94202 GUI
EEPROM TAB
ISL94202 GUI
PACK SETTINGS TAB
2
1
TRANSLATE
1
2