Intersil ISL1208 Installation and operating instructions

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®
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CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
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Real Time Clock USB Evaluation Board
Introduction
This evaluation board provides a platform for testing the
ISL1208 and ISL1209 Real Time Clock (RTC) devices.
Device features include a crystal oscillator, clock and date
counters, and an alarm. The ISL1209 device includes an
event-detection feature for recording the time of an event.
The evaluation board provides a platform to test all of these
functions, as well as evaluate device performance criteria,
such as long-term clock accuracy. Hardware options such as
battery and crystal types can also be tested. The software is
designed to allow easy setup and monitoring of all major
device functions. The two-piece construction utilizing a
motherboard and a daughtercard enables the board and
software to operate the RTC device residing on a remote
board.
FIGURE 1.
Operation of the RTC Evaluation Board
Hookup and Power
CONNECTIONS
The eval board consists of a motherboard and daughtercard
and these need to be connected together. The evaluation
board uses hardware and software from FTDI for USB
communications and these drivers must be installed on each
PC that talks to the RTC eval board. A USB cable, with type
A and B connectors on the ends, is required to hook up the
board to a PC. The cable should be connected to the PC first
and then to the eval board. Once connected, LED1 will
illuminate indicating +5V power is available from the USB
cable.
POWERING DOWN
The daughter card contains backup power, consisting of a
battery or supercap. When powering down, the
daughtercard will operate off the backup source determined
by JP2 (after the VCC voltage discharges from the VCC
supply capacitors). If the user wishes to totally power down
the RTC device once VCC is removed, then either remove
the daughtercard from the motherboard or set JP2 to GND.
Keep in mind there is a decoupling capacitor on the
daughtercard (0.1µF) which must discharge fully before the
RTC device stops operating. This discharge time can be up
to one second when using a VCC of 5V. Note that when
powered down, the RTC board cannot be monitored by the
RTC software.
Installing the RTC Software and USB Drivers
USB DRIVERS AND COM PORT SETUP
Insert the Intersil RTC_USB CDROM in the PC to be used.
Open the folder “Install USB”. Then open the ZIP file
“FTDI.zip”. Extract this set of files to a separate folder on
your main hard drive. For example, create a folder titled
“FTDI” on your C: drive, then extract the contents of the ZIP
file to that folder. In the “Install USB” folder, there is a pdf file
titled “Windows Drivers Installation Guide”. Open that file
and follow the instructions for the FTDI 232 device (you will
need to connect the RTC_USB Eval Board to your PC’s USB
port, this will bring up a prompt to install the USB hardware
and software drivers).
Note that both a hardware AND a software driver need to be
installed for correct USB operation. These are two
procedures that are best done sequentially per the FTDI
Installation Guide.
Once the USB drivers are loaded, locate the RTC program,
titled “Intersil 12xx_2.exe” on the CD. This program can be
placed anywhere on the PC, or may be run from the CD.
Double-click to execute the program (note that the “.._2”
may be changed as the program is updated and the revision
changes).
After starting the program, an error window may appear
indicating that a certain COM port is not available. Dismiss
this window by clicking “OK”. A timeout error may follow and
this should be dismissed as well.
On the Intersil RTC Data Analyzer main window, click on the
“Setup” pulldown menu. Click on “Autodetect” and the
program will search each COM port to find which is
connected to the USB device on the eval board. A small
“COM Auto Detect” window will appear and monitor the
polling process. Once the correct COM port is detected, it is
noted in the “COM Auto Detect” window and that window will
close. If you wish to review which COM port is being used,
just click again on the “Setup” pulldown menu.
If no COM port is detected, make sure the board is
connected to the PC with a USB cable and that the board
jumpers are in the appropriate places (see hardware
section). If there is still no COM port detected after any
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corrections, see the troubleshooting section at the end of
this document.
If the COM port number is known in advance (it may be
located by looking in the Hardware Device Manager on your
PC while the board is plugged in), it may be selected
manually by using the setup menu. The software may then
be used normally.
Software Time/Date Operation
After opening the RTC program, you will be viewing the RTC
Data Analysis Screen. The RTC device requires an initial
write to the clock/calendar registers to begin keeping time.
Open the “Set RTC date and time” window and by clicking
on the clock icon in the menu bar. The easiest way to set the
current time is to click the “Set date and time from PC clock”
button, although the time and date can be manually entered
using the calendar and time windows. Also choose the time
format, either 12- or 24-hour. When complete, click on
“Done”, bringing you back to the RTC data analyzer window.
Next, click on the “Poll RTC” button. The PC Time, RTC
Time, and RTC Deviation windows should constantly update
with their respective information. This is the normal mode for
RTC operation/monitoring. If the RTC Time fails to update or
is not set correctly, use the following troubleshooting steps.
1. RTC time stuck at 12:00:00 and not advancing The
proper time was not initially written to the RTC registers.
Go back to the “Set RTC Time and Date” window and set
the time again. Also, be sure to check the USB cable
hookup and daughtercard connections to insure these
are correct.
2. RTC time is showing widely varying readings, not
consistent and advancing Most likely the eval board
was plugged in after the software was started, which
causes issues. Exit the software program (File > Exit, or
the X in the upper right corner), and re-open the program.
It should detect the board and function correctly.
As the program polls the RTC and updates time, there will be
a difference between the RTC time and the PC time due to
finite PC communications delays. This should be a constant
+1 or -1 second difference, and the window will alternately
display between zero and one-second error.
As the RTC or the PC clock drifts, the RTC time window will
change color. If the RTC time is faster than PC time, the
window will turn red, first light red then dark red, as the error
increases. If the RTC time is slower than PC time, the
window will turn blue, first light blue then dark blue, as the
error increases.
During Polling the temperature of the daughtercard is
displayed and updated once per second as well. The ATR
register is also displayed, but will likely not change unless
Temperature Compensation feature has been enabled
(discussed later).
The Polling can be turned off by clicking on the polling button
again. The RTC device will still be keeping time, and when
Polling is turned on again, it will display the RTC current
time.
Modifying RTC Registers
Open the RTC Register screen using the shortcut key in the
menu bar (the group of 1s and 0s). The RTC Registers are
available using the pulldown menu on the left. Using these
registers, the functions of the RTC device can be enabled,
modified, or monitored, including:
• Frequency output
• Alarm settings
• Analog Trimming Registers (ATR)
• Digital Trimming Registers (DTR)
• Event-Detection (ISL1209 only)
The clock/calendar registers are available also, but are more
easily modified by using the clock/calendar window.
Once the correct register is located, the byte is displayed in
the horizontal window along with its hex value. Changes to
the individual bits can be made by clicking on a location. A
zero is indicated with a white background, and a one is
indicated by yellow background. Once the value of the byte
is set, the byte is written to non-volatile memory by clicking
on “Write”. A register value can be read by clicking on
“Read”.
Using the RTC Deviation/Temperature Recorder
The program is able to record continuous time
measurements of the RTC deviation from PC Clock and the
board temperature and create a plot of the results. Time
frames from a few minutes to many days are possible. From
the RTC Data Analysis screen, first select the deviation
range from the lower right set of pulldown windows. The
Temperature Range and Time Base should also be set as
desired from their pulldown windows.
Set the RTC time from the PC time as described above (see
Software Time/Date Operation section). This will insure the
PC time is close to the RTC time to begin recording.
To begin recording, select “Start” from the “Record Data”
pulldown menu (or click on the right arrow in the menu bar).
Data will be recorded periodically until the end of the time
frame selected or until the Stop function is selected. Note
that multiple samples are recorded and averaged before
being plotted on the chart recorder.
The status of the recorder is shown in the windows at the
bottom of the RTC Data Analysis screen. These windows will
continually update with information on the data recording.
Recorded data can be saved to a file, as well as imported
from a saved data file.
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Note that for long recordings of deviation, it is advisable to
use a PC program that automatically updates the PC time,
such as that available from NIST:
http://www.boulder.nist.gov/timefreq/service/its.htm
Temperature Compensation
Compensation for crystal frequency variation over
temperature is accomplished using the Temperature
Compensation Settings window. Click on the thermometer
icon in the menu bar to open this window. There are six
different ranges of temp control available from 0°C to 60°C.
Slide the control bar up or down to change the setting for a
particular range. To save settings, click the Write button.
Click on the Temperature Compensation Enabled button
start using the temp compensation. Note that when using the
data recorder is functioning, temp compensation is
automatically enabled.
DEVIATION STATISTICS
Click the Bell curve icon in the menu bar. The time and
temperature statistics are presented here for the current
chart recorder data.
DAUGHTERCARD ON/OFF CONTROL
The normally open switch icon in the menu bar controls
whether VCC power is applied to the daughtercard. Click on
the icon once to shut off VCC power and the icon will turn
from black to grey. Click again on the icon to reapply VCC
power and the icon will turn black. Note that when VCC
power is turned off, the RTC device will operate from backup
power selected by JP2 on the motherboard. No
communication with the device is possible in backup mode.
Event-Detection Software
The Event-Detection window (shown here) is opened by
clicking on the pushbutton switch icon in the menu bar. The
button functions are defined as follows:
FIGURE 2. EVENT-DETECTION WINDOW
ENABLE EVENT MODE
This will enable the event detection function (set EVEN bit to
“1”) and put it into a standard mode with input debouncing
enabled (ESYSx set to 01) and sampling enabled (ESMPx
set to 01). The Event Register is set to 00010101b. The
software will poll the Status Register once per second to test
the EVT bit. If the EVT bit is set to “1”, then the software will
read and display the time of the event.
DISABLE EVENT MODE
Disables the Event Mode. Resets the EVEN, EVENx, and
ESMPx bits to “0”and stops polling of the Event Register.
CLEAR EVENT
Resets the EVT bit to “0”. The Event Input will ignore any
activity on the Event Input pin while the EVT bit is set to 1.
CLEAR EVENT LOG
This will clear the window display of all recorded times of
events. The window display will retain the list of events, even
when closed, until the Clear Event Log button is selected.
Hardware and Software Detailed
Descriptions
USB RTC Evaluation Board - General Description
The evaluation board consists of the motherboard and
daughtercard. The motherboard contains all the main
support functions for the RTC device, including:
• Microcontroller for communicating with the PC and the
RTC using serial interfaces.
• USB interface IC for translating the PC USB interface to
the microcontroller serial port interface.
• Regulator to produce 3.3V from the 5V board supply.
• Connectors for the USB interface and the daughtercard.
• A 0.22F supercapacitor and a 3V CR2032 lithium battery
for backup power.
• Jumpers for selecting the backup battery or
supercapacitor, and also for selecting the VCC voltage of
5V or 3.3V.
• A MOSFET switch for disconnecting the VCC supply to the
daughtercard for backup testing.
• EEPROM and microprocessor reset (X40411) for storing
temperature data.
The daughtercard contains the Intersil RTC device, crystal,
temperature sensor IC, decoupling capacitor, and pullup
resistor for the open drain output.
Evaluation Board - Functional Description (see
Figure 3 and schematic file RTC_USB_schem.pdf)
POWER SUPPLY
The motherboard draws its power from the USB +5V ±5%
supply. If the eval board is used to provide power for other
circuitry, care must be taken to keep the current draw on this
supply well below 500mA which is the maximum for a USB
hub-type device. There is an on-board regulator (ICL7663,
U2) which produces 3.3V. The VCC for the Intersil RTC chip
as well as the serial interface pullup resistors is selectable
using JP1 for either 3.3V or 5V. VCC power can be obtained
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by clipping a test lead to the JP1 shunt, or if an external VCC
supply is used it should be connected to the center pin of
JP1 (shunt is removed). A ground connection is available at
J3.
BACKUP SUPPLY
There are two sources of backup supply available. A 0.22µF
supercapacitor (C10) is on the board. It will provide enough
backup power for the typical RTC chip to last many days at
room temperature when VCC is set to 5V. There is also a
CR2032 battery included in a socket to allow removal/
replacement without soldering. This battery will last up to ten
years in normal backup operation. The backup supply is
selectable via jumper JP2 as shown in Figure 3. One row of
JP2 is connected to the device VBACK, and the other row to
the power sources. There are three positions possible on
JP2, Supercap, Battery, and Ground. If no backup is used
the Ground position should be used. The jumper may be
removed altogether and an alternative source for VBACK can
be attached to the board via the exposed header.
MICROCONTROLLER
The microcontroller used is the PIC16C63A. It has a
dedicated serial interface which connects to the FDTI USB
device. There is a dedicated I2C serial interface connected
to the Intersil RTC device, EEPROM, and the temperature
sensor. The power for the microcontroller comes from the
USB 5V input, so the microcontroller will always be powered
from 5V. Note that the RB1 to RB4 I/O pins for the
microcontroller are available at the daughtercard connector,
J3. This is to enable identification of the RTC daughtercard
and thus enable functions for a particular device family. The
device is socketed to allow removal or replacement for
development activity and software upgrades with a newly-
programmed device.
DAUGHTERCARD CONNECTOR (J3)
This connector provides power and interface signals to the
daughtercard containing the Intersil RTC device as follows:
Pin 1: VCC
Pin 2: RB4
Pin 3: RB3
Pin 4: RB2
Pin 5: RB1
Pin 6: RB0 or Event Input
Pin 7: SDA
Pin 8: SCL
Pin 9: VBAT
Pin 10: GND
This configuration allows these signals to control the Intersil
device on an external board by connecting the serial
interface and ground, available at the connector. Also
available are the RB0 to RB4 I/O signals from the
microcontroller (see Microcontroller section).
SUPERCAP
BACKUP
BATTERY
SOCKET
VCC SELECT
DAUGHTERBOARD
CONNECTOR
SHUNT
FOR VBACK
SELECT
FIGURE 3. RTC-USB MOTHERBOARD LAYOUT
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USB connector (CN1). This connector is a standard USB
type B connector which goes to the USB port of a PC using a
USB type A-B cable.
LEDs
There are three surface-mounted LEDs on the board. LED2
and LED3 monitor the TX and RX functions of the serial port.
They should be observed to insure that communication is
taking place with the serial port. LED1 monitors the power
supply and will light when the +5V power is applied from the
USB cable.
ISL1208 Daughtercard - Functional Description
(see Figure 4)
The ISL1208 daughtercard contains the ISL1208 device,
crystal, decoupling capacitor, temp-sensor, and an LED
(D1), for monitoring the open drain output.
FIGURE 4. ISL1208 DAUGHTERCARD
POWER
Jumper JP1 connects to the VCC pin of the ISL1208 device
and must have a shunt in place for the device to function in
normal mode.
OPEN DRAIN OUTPUT
The open drain output of the ISL1208 is the IRQ-FOUT
signal. There is a jumper (JP2) which connects D1 when a
shunt is in place, and also enables hooking up an external
pullup resistor if it is desired to use the logic signal. The
pullup resistor should terminate to a voltage that is less than
or equal to VCC.
CRYSTAL
A standard 32.768kHz surface-mounted crystal is supplied
on the daughtercard. A through-hole device can only be
attached by surface mounting the leads after the surface
mount device is removed.
TEMPERATURE SENSOR
There is an LM76 temperature sensor on the board which
measures ambient temperature, digitizes it, and provides it
to the microcontroller when prompted. Mounting on the
daughtercard enables remote sensing of temperature should
the daughtercard be placed in a temp chamber and wired to
the motherboard.
MEASUREMENTS
The VCC supply current may be monitored by adding a
series ammeter to JP1. D1 provides visual indication of IRQ-
FOUT status, and at low frequencies it will indicate that FOUT
is enabled. At higher FOUT frequencies it is possible to
monitor the pin with an oscilloscope. This allows good
monitoring of the crystal frequency, up to 32kHz. It is
possible to probe the X2 oscillator output with a scope
probe, but this is not recommended as it alters the oscillator
frequency or possibly stop it momentarily due to introduction
of a transient. If it is absolutely necessary to monitor the
oscillator output, use a low-capacitance probe (<2pF) or an
active probe and note that the absolute frequency monitored
will be higher than that without the probe.
ISL1209 Daughtercard - Functional Description
(see Figure 5)
The ISL1209 daughtercard contains the ISL1209 device,
crystal, decoupling capacitor, temp-sensor, and an LED
(D1), for monitoring the open drain output, similar to the
ISL1208 daughtercard. In addition there is a microswitch,
S1, and a connection block, J3, for the event-detect function.
Also, another LED (D2) is available for event monitoring.
The main functions of this daughtercard are similar to the
ISL1208. The important differences are discussed here.
EVENT-DETECT SWITCH, S1
This is a normally CLOSED switch which is typically
connected to ground. A shunt should be installed on J3 from
the EVT to GND position for this purpose. Depressing the
switch with the event detection software enabled will cause
an event to be recorded.
EVENT-DETECT OUTPUT
The event-detect output is open-drain and can be connected
to LED D2 by placing a shunt on JP3. With this output
enabled, the LED will light when an event occurs.
EVENT CONNECTION BLOCK
J3 contains all signals needed to connect a remote event
generating circuit to the evaluation board. VCC, VBAT
, the
EVIN device input (labeled EVI), Ground, and a high value
pulldown resistor are all brought to this block. The 6th
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position is unused. Default connection is for a shunt to be
placed across the EVI and GND terminals. Note that if VCC
is used to provide power to remote circuitry, that current
should be limited to less than 50mA to prevent loading the
power switch, shunts, and board traces. The VBAT
connection should likewise be limited to less than 10mA to
maintain reasonable battery life.
EVENT INPUT, J2
This can be used as a separate input for event detection. If
the connections on J3 are left open, then a normally closed
switch can be connected across J2 for event detection. Pin 1
(square pad) is the input and the other pin is ground.
Troubleshooting
This section will cover commonly-encountered problems in
both hardware and software/USB connections and how to
solve them.
Hardware Troubleshooting
1. Device doesn’t respond to software commands
Check the VCC select shunt on JP1 on motherboard to
make sure it is in place for either 5V or 3.3V VCC. Check
shunt on JP1 on daughtercard to make sure its installed
or an ammeter is connected across the terminals.
2. Device loses time or resets to zero time in backup
mode Check shunt on JP2 to make sure it is on either
supercap or battery setting. Check to make sure a battery
is installed in BT1 socket if using battery backup power.
3. Power LED doesn’t light when plugging into USB
cable This can happen on older PCs that do not have
sufficient USB +5V power or may have had a that power
fail. Try the board on another PC.
4. Software reads incorrect time when using FREQ
output LED and VCC = 3.3V In this mode it is possible to
get enough noise on the VCC line to cause
communications problems with the microcontroller. If
FREQ output testing is done at VCC = 3.3V, it may be
necessary to disable the FREQ output when doing other
tests, or use an external pullup of value >10kΩconnected
to JP2 of the daughtercard.
5. ISL1209 board - device shows event is detected
immediately after clearing an event This indicates the
event switch is open continuously or the event pin is
open. The event pin needs to be held to ground (normally
closed) in order to detect an event.
Software and USB Troubleshooting
Keep in mind that the RTC_USB board uses a serial to USB
converter to communicate, therefore it needs to have a COM
port assigned to it. Many problems can be solved quickly by
noting the COM port number for the PC your are using and
checking the setup menu in the software for that COM port.
Using the Autodetect function in the setup menu will usually
do this automatically for you.
Also note that the serial USB drivers will only work on
WIN98, WIN2000, and EXP machines. WIN NT and earlier
operating systems will not work with the drivers.
1. Software doesn’t communicate with the evaluation
board (Error message “timeout waiting for a
response from device”)
a. First make sure all connections are secure, USB
cable at PC and eval board, and also the
daughtercard connector. If no daughtercard is
connected then there will be an error message. Also
check VCC shunts on the motherboard (JP1) and
daughtercard (JP1) are installed.
b. Check COM port used. Although there are 256
possible COM port addresses, the RTC software will
only use the first eight. COM ports 1 and 2 are used
for serial port communications and should be avoided
if the serial port is used. In the FTDI Windows
installation guide and app note, it shows a simple
procedure to change COM ports. Make sure the COM
port selected for the FTDI device is the same as that
selected by the PC. If one COM port is not working,
change to another and try again.
c. The software was opened before the board was
plugged into the USB cable. This will cause setup
problems. Close the software (exit program) and
reopen. If still not working, close software, unplug
board, wait a few seconds, then plug the board in and
open the software.
d. Multiple USB drivers in system. Check the Hardware
Uninstall window (WIN98, WIN2000) and see if there
are multiple serial USB devices shown. Uninstall any
extra ones. Also, check the number of other USB
devices shown. There may be other multiple USB
drivers and some may need to be uninstalled to
resume correct communications.
EVENT INPUT
CONTROL BLOCK
EVENT INPUT
SWITCH
EVENT INPUT
(ALTERNATIVE)
FIGURE 5. ISL1209 DAUGHTERCARD
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2. Error Message
3. PC just will not recognize the USB_RTC board If this
happens and all methods described above haven’t
helped, then uninstall the drivers using the FTDI uninstall
program (see the Installation Manual on the CD). Then
install the drivers again and check for proper operation.
Suggested RTC Tests
ISL1208 or ISL1209
1. Set time of day and turn on time and temperature
recorder Board can now be exposed to temperature,
shock, or other environmental influences to determine
effects on time accuracy. Main VCC can be turned on and
off to determine backup mode accuracy. Note that the
motherboard devices are only rated for commercial
temperature range (0°C to 70°C), but the RTC crystal is
good for full -40°C to +85°C. If wide temperature range
testing is desired, then the daughtercard can be placed in
a chamber with remote wiring from the motherboard to
the daughtercard. Consult the schematics for the boards
for any details on the connections.
2. Test the frequency output (FREQ) Go to register 08h
(INT) and set bits 0 to 3. Note that the LED D1 will
illuminate or flash to indicate FREQ is active (or alarm
has occurred). This LED will go off if the VCC is shut
down. The jumper JP2 will allow connection to an
external pullup or separate board for other tests. Note
that a ground connection will be required as well,
available at the motherboard (J3). Be careful with low
external pullup values (<10kΩ) as the decoupling on the
daughtercard may allow large voltage dips when the
open drain output is turned ON.
3. Test the temperature compensation feature Do a
temperature test as in #1, but enable the Temperature
Compensation function as described previously in the
instructions. The sliders can be used to set the value of
the ATR registers, and then those settings are saved by
clicking the Save button, then clicking to Enable
Temperature Compensation button. Note that it will take
many days to see small drifts of time with temperature,
but if a frequency counter is available a frequency test
can be done as the temp changes. Enable the frequency
output as in #2. Add a pullup resistor (10k or higher
advised) from JP2, pin 2 (daughtercard) to VCC
(available at the shunt of JP1, motherboard). The counter
can then be connected to the JP2-2 connection and
ground, and the absolute frequency monitored on the
counter. For best results it is suggested to use the 1.0Hz
frequency selection and use seven or more digits of
counter resolution to get one PPM of accuracy.
4. Test the ICC An ammeter can be connected in series with
the JP1 terminals to monitor the VCC supply current to
the device. Note that when using the software and polling
is enabled, the ICC will increase and vary quite a bit when
the serial interface is communicating.
5. Test the backup supply current, IBAT An ammeter can
be connected between the terminals of the backup
source and the VBAT input on JP2 of the motherboard.
Only one source may be selected at a time, so the shunt
needs to be removed when doing this. Click on the
normally closed switch icon in the menu bar to disconnect
VCC, then monitor the IBAT current.
6. Talk to an RTC device on a remote board Use the
motherboard connector pins and jumper wires to enable
communications with an RTC device on a separate test
board. The SDA, SCL and ground pins are mandatory for
this, and the test board Vcc should match the
motherboard Vcc within 5% for best results.
lSL1209 Only
The ISL1209 eval board provides event-detection functions
and includes special pins for external circuitry.
1. Test the event detection function The on-board switch
can be tested by connecting a shunt from the EVT to the
GND pins on J3 of the ISL1209 daughtercard. Then open
the Event Detection window by clicking on the pushbutton
switch icon in the menu bar, and enable event detection.
Any touch of the event detect switch will result in a
recorded event. Manually setting event-detect function
and options can also be done by writing to register 09h.
Please see the ISL1209 data sheet for details on event
detection options.
2. External event detection switches Since the switch
function is a Normally Closed (NC) function, external
circuits must use a break in the circuit to cause a
recorded event. Such breaks are possible using foil with
wire contacts inside of an enclosure or on a door frame.
Note that a long wire return is required on the door itself.
For simple switch circuits such as these, remove the
shunt from J3, and run wires from J2 to the external
switch.
3. External event detection circuits Since the ISL1209
Event Input is triggered by a low to high transition, and
the internal pullups can be disabled, external comparator
circuits can be used to trigger an event. Such circuits can
detect light or darkness, sound, movement, or
temperature limits. The connector J3 has and event input
pin, as well as VCC and VBAT supply pins, a ground pin
and a 10MΩpulldown to ground. These signals can be
jumpered over to another board to enable event detection
circuits that run from VCC or VBAT
, and can remotely
trigger the event pin.
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Using the RTC-USB Motherboard with
Older X1227 Daughtercards
The RTC-USB board is compatible with and can be used
with the older X1227 daughtercards that were supplied with
the serial-port based evaluation platform, similar to the USB
platform. The USB motherboard will actually detect the
X1227 daughtercard and enable communications with that
register set. Here are the specifics required:
1. Plug the daughtercard into the motherboard then plug
into the USB cable. Then open the software which will run
the detection program.
2. Once the software is running, all functions available on
the eval board can be used. Note that there is no temp
sensor on the X1227 daughtercard, so there is no temp
monitoring available.
3. The X1227 device has a watchdog timer function that can
inhibit communications if it is enabled. To disable it, you
must repeatedly write to the BL register of the X1227 (see
the X1227 data sheet) until the write is accepted by the
device.
RTC Motherboard Bill of Materials
DESIGNATOR PART TYPE FOOTPRINT DESCRIPTION MFR PART # MFR PART NUMBER
BT1 CR2032 Socket BATTX Battery and Socket MPD BS-3-ND Panasonic
or other
CR2032
C1 0.1µF 1206 0.1µF 50v X7R
Ceramic Aurface
Mount
AVX 12065C104KAT2A * *
C10 0.22F SCAP SCAP 0.22F 5.5V Super
Cap - Through Hole
Panasonic EEC-S0HD224H DigiKey P10788-ND
C2 0.1µF 1206 0.1µF 50v X7R
Ceramic Surface
Mount
AVX 12065C104KAT2A * *
C3 18pF 1206 22pF 50v NPO
Ceramic Surface
Mount
AVX 08055A220KAT2A * *
C4 18pF 1206 Capacitor AVX 08055A220KAT2A * *
C5 10µF CAP SMB 10µF 10v Tantalum
Surface Mount
Panasonic ECS-T1AY106R * *
C6 0.01µF 805 Capacitor * *
C7 0.1µF 1206 Capacitor * *
C8 20p 1206 Capacitor * *
C9 20p 1206 Capacitor * *
C11 0.033µF 1206 Capacitor * *
CN1 CN-USB USB_CONN Molex 67068-1000
D1 1N4148 MiniMELF Diode * *
FB1 FERRITE
BEAD
805 DigiKey #
240-1018-1
*
J1 CON2 CONN_2 Connector * *
J3 CON1 CONN_1 Connector * *
J2 CON10 CONN_10 Connector Samtec TSW-110-08-
G-S-RA
JP1 HEADER 3 CONN_3 Single Row Header,
Breakaway, Tin Finish,
Straight
Molex * *
JP2 HEADER 3X2 CONN_3X2 Dual Row Header,
Breakaway, Tin Finish,
Straight
Molex * *
Application Note 1176

9AN1176.0
June 20, 2005
LED1 RED SM LED 1206 LED Red Low Current LED
Surface Mount
Lumex SML-LX23IC-TR * *
LED2 GREEN SM
LED
1206 LED Green Low Current
LED Surface Mount
Lumex SML-LX23GC-TR * *
LED3 YELLOW SM
LED
1206 LED Yellow Low Current
LED Surface Mount
Lumex SML-LX23YC-TR
M1 SI3443BDV TSOP-6 P-channel MOSFET Siliconix SI3443BDV * *
R1 470 1206 1/8W 5% Carbon
Comp. Surface Mount
680Ω**
R10 2.2K 1206 Resistor * *
R11 200K 1206 Resistor * *
R12 130K 1206 Resistor * *
R13 20K 1206 Resistor * *
R14 100K 1206 Resistor * *
R15 100K 1206 Resistor * *
R16 100K 1206 Resistor * *
R17 100K 1206 Resistor * *
R18 47K 1206 Resistor * *
R2 10K 1206 * *
R3 27 1206 * *
R4 27 1206 * *
R5 470 1206 * *
R6 330 1206 470Ω**
R7 330 1206 Resistor * *
R8 1.5K 1206 * *
R9 2.2K 1206 Resistor * *
U1 PIC16C63A SDIP28 PIC 16C63 8-bit
CMOS Microcontroller
Through Hole
Socket 28-DIP x 0.3" Microchip PIC16C63A-04/SP
U2 ICL7663CBA LSOIC8 Dual Mode 5V
Programmable
Micropower Voltage
Regulators
Intersil *
U3 FT232BM QUAD32 USB to Serial
Converter
FTDI FT232BM
U4 X40411-A MSOP8 Dual Supply Monitor
with 4K EEPROM
Intersil X40411IV8-A
X1 CTS
3.57954MHZ
XTAL_1 3.579545MHz 18pF
Crystal Surface Mount
DigiKey CTX400-ND CTS MP036S
Y1 6MHz XTAL_1 Crystal DigiKey CTX405-ND CTS MP060
SH1 - SH4 Shunts 0.1" 0.1" Shunt, Closed
Top, Tin Plated
DigiKey Molex 15-38-1026
RTC Motherboard Bill of Materials (Continued)
DESIGNATOR PART TYPE FOOTPRINT DESCRIPTION MFR PART # MFR PART NUMBER
Application Note 1176

10
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
AN1176.0
June 20, 2005
ISL1208 Bill of Materials
DESIGNATOR PART TYPE FOOTPRINT DESCRIPTION MFR MFR PART NUMBER PART NUMBER
C1 0.1µF 1206 Capacitor * * *
R1 360 1206 Resistor * * *
J1 CON10 CONN_10_A Connector Samtec SSQ-110-02-S-S-RA *
JP1 HEADER 2 CONN2 Molex 0.1" 2-pin header *
JP2 HEADER 2 CONN2 Molex 0.1" 2-pin header *
U2 LM76 LSOIC8 Temperature
Sensor, Digital
National LM76CHM-5 DigiKey LM76CHM-5-ND
D1 LTST-C230KRKT 1206 LED RED LTST-C230KRKT DigiKey #160-1457-2-ND
Y1 MC-206 XTL_206 Crystal Epson SE2406CT-ND MC-206 32.768KA-A2
U1 X1208 SO-8 RTC Intersil ISL1208S8I *
ISL1209 Bill of Materials
DESIGNATOR PART TYPE FOOTPRINT DESCRIPTION MFR MFR PART NUMBER PART NUMBER
C1 0.1µF 1206 Capacitor * * *
D1 LTST-C230KRKT 1206 LiteOn LTST-C230KRKT DigiKey #160-1457-2-ND
D2 LTST-C230KGKT 1206 LiteOn LTST-C230KGKT DigiKey #160-1456-2-ND
J1 CON10 CONN_10_A Connector Samtec SSQ-110-02-S-S-RA *
J2 CON2 CONN2 Connector Molex 0.1" 2-pin header *
J3 HEADER 3X2 CONN3X2 Tyco 534206-3 DigiKey #A26453-ND
JP1 HEADER 2 CONN2 Molex 0.1" 2-pin header *
JP2 HEADER 2 CONN2 Molex 0.1" 2-pin header *
JP3 HEADER 2 CONN2 Molex 0.1" 2-pin header *
R1 360 1206 Resistor * * *
R2 360 1206 Resistor * * *
R5 10M 1206 Resistor * * *
S1 KSM-11310 KSM_3 Tactile momentary
NC switch
ITT-Cannon KSM-11310 DigiKey #401-1092-1-ND
U1 X1209 MSOP10 RTC and Event
Detect
Intersil ISL1209S8I *
U2 LM76 LSOIC8 Temperature
Sensor, Digital
National LM76CHM-5 DigiKey LM76CHM-5-ND
Y1 MC-206 XTL_206 Crystal Epson SE2406CT-ND MC-206 32.768KA-A2
Application Note 1176