DATASHEET

X4043, X4045
4k, 512 x 8 Bit
Data Sheet
December 9, 2015
CPU Supervisor with 4kbit EEPROM
FN8118.3
DESCRIPTION
The X4043/45 combines four popular functions,
Power-on Reset Control, Watchdog Timer, Supply
Voltage Supervision, and Block Lock Protect Serial
EEPROM Memory in one package. This combination
lowers system cost, reduces board space requirements, and increases reliability.
FEATURES
• Selectable watchdog timer
• Low VCC detection and reset assertion
—Five standard reset threshold voltages
—Adjust low VCC reset threshold voltage using
special programming sequence
—Reset signal valid to VCC = 1V
• Low power CMOS
—<20µA max standby current, watchdog on
—<1µA standby current, watchdog OFF
—3mA active current
• 4kbits of EEPROM
—16-byte page write mode
—Self-timed write cycle
—5ms write cycle time (typical)
• Built-in inadvertent write protection
—Power-up/power-down protection circuitry
—Protect 0, 1/4, 1/2, all or 16, 32, 64 or 128 bytes
of EEPROM array with Block Lock™ protection
• 400kHz 2-wire interface
• 2.7V to 5.5V power supply operation
• Available packages
—8 Ld SOIC
—8 Ld MSOP
—8 Ld PDIP
• Pb-free plus anneal available (RoHS compliant)
Applying power to the device activates the power-on
reset circuit which holds RESET/RESET active for a
period of time. This allows the power supply and oscillator to stabilize before the processor can execute code.
The Watchdog Timer provides an independent protection
mechanism for microcontrollers. When the microcontroller fails to restart a timer within a selectable time
out interval, the device activates the RESET/RESET
signal. The user selects the interval from three preset
values. Once selected, the interval does not change,
even after cycling the power.
The device’s low VCC detection circuitry protects the
user’s system from low voltage conditions, resetting the
system when VCC falls below the minimum VCC trip
point. RESET/RESET is asserted until VCC returns to
proper operating level and stabilizes. Five industry standard VTRIP thresholds are available, however, Intersil’s
unique circuits allow the threshold to be reprogrammed
to meet custom requirements or to fine-tune the threshold for applications requiring higher precision.
BLOCK DIAGRAM
Watchdog Transition
Detector
WP
Data
Register
Command
Decode &
Control
Logic
VCC Threshold
Reset logic
VCC
+
VTRIP
1
RESET (X4043)
RESET (X4045)
Status
Register
EEPROM Array
2Kbits 1Kb 1Kb
SCL
Protect Logic
Block Lock Control
SDA
Watchdog
Timer Reset
-
Reset &
Watchdog
Timebase
Power-on and
Low Voltage
Reset
Generation
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Copyright Intersil Americas LLC 2005, 2006, 2015. All Rights Reserved
Intersil (and design) and XDCP are trademarks owned by Intersil Corporation or one of its subsidiaries.
All other trademarks mentioned are the property of their respective owners.
X4043, X4045
Ordering Information
PART NUMBER RESET
(ACTIVE LOW)
PART
MARKING
PART NUMBER RESET
(ACTIVE HIGH)
PART
MARKING
VCC
VTRIP
TEMP
RANGE RANGE RANGE
(°C)
(V)
(V)
PACKAGE
X4043S8Z-4.5A (Note)
X4043 Z AL
X4045S8Z-4.5A (Note)
X4045 Z AL
4.5-5.5 4.5-4.75 0 to 70 8 Ld SOIC (Pb-free)
X4043S8IZ-4.5A (Note)
X4043 Z AM
X4045S8IZ-4.5A (Note)
X4045 Z AM
-40 to 85 8 Ld SOIC (Pb-free)
X4043M8Z-4.5A (Note)
DAZ
DBH
X4045M8Z-4.5A (Note)
(No longer available,
recommended replacement:
X4045S8Z-4.5A)
0 to 70 8 Ld MSOP (Pb-free)
X4043M8IZ-4.5A (Note)
DAU
DBE
X4045M8IZ-4.5A (Note)
(No longer available,
recommended replacement:
X4045S8IZ-4.5A)
-40 to 85 8 Ld MSOP (Pb-free)
X4043P Z AL
X4043PZ-4.5A (Note)
(No longer available,
recommended replacement:
X4043M8Z-4.5A)
X4045P Z AL
X4045PZ-4.5A (Note)
(No longer available,
recommended replacement:
X4045S8Z-4.5A)
0 to 70 8 Ld PDIP (Pb-free)
X4043P Z AM
X4043PIZ-4.5A (Note)
(No longer available,
recommended replacement:
X4043M8IZ-4.5A)
X4045P Z AM
X4045PIZ-4.5A (Note)
(No longer available,
recommended replacement:
X4045S8IZ-4.5A)
-40 to 85 8 Ld PDIP (Pb-free)
X4043S8Z* (Note)
X4043 Z
X4045S8Z* (Note)
X4045 Z
X4043S8IZ* (Note)
X4043 Z I
X4045S8IZ (Note)
X4045 Z I
X4043M8Z* (Note)
DAW
DBD
X4045M8Z (Note)
(No longer available,
recommended replacement:
X4045S8Z)
0 to 70 8 Ld MSOP (Pb-free)
X4043M8IZ (Note)
DAR
DBA
X4045M8IZ (Note)
(No longer available,
recommended replacement:
X4045S8IZ)
-40 to 85 8 Ld MSOP (Pb-free)
4.5-5.5 4.25-4.5 0 to 70 8 Ld SOIC (Pb-free)
-40 to 85 8 Ld SOIC (Pb-free)
X4043P
X4043PZ (Note)
(No longer available,
recommended replacement:
X4043M8Z)
X4045P Z
X4045PZ (Note)
(No longer available,
recommended replacement:
X4045S8Z)
0 to 70 8 Ld PDIP (Pb-free)
X4043P Z I
X4043PIZ (Note)
(No longer available,
recommended replacement:
X4043M8IZ)
X4045P Z I
X4045PIZ (Note)
(No longer available,
recommended replacement:
X4045S8IZ)
-40 to 85 8 Ld PDIP (Pb-free)
2
FN8118.3
December 9, 2015
X4043, X4045
Ordering Information
PART NUMBER RESET
(ACTIVE LOW)
PART
MARKING
PART NUMBER RESET
(ACTIVE HIGH)
PART
MARKING
VCC
VTRIP
TEMP
RANGE RANGE RANGE
(°C)
(V)
(V)
PACKAGE
X4043S8Z-2.7A* (Note)
X4043 Z AN
X4045S8Z-2.7A (Note)
X4045 Z AN
2.7-5.5 2.85-3.0 0 to 70 8 Ld SOIC (Pb-free)
X4043S8IZ-2.7A* (Note)
X4043 Z AP
X4045S8IZ-2.7A (Note)
X4045 Z AP
-40 to 85 8 Ld SOIC (Pb-free)
X4043M8Z-2.7A (Note)
DAY
DBG
X4045M8Z-2.7A (Note)
(No longer available,
recommended replacement:
X4045S8Z-2.7A)
0 to 70 8 Ld MSOP (Pb-free)
X4043M8IZ-2.7A (Note)
DAT
DBC
X4045M8IZ-2.7A (Note)
(No longer available,
recommended replacement:
X4045S8IZ-2.7A)
-40 to 85 8 Ld MSOP (Pb-free)
X4043P Z AN
X4043PZ-2.7A (Note)
(No longer available,
recommended replacement:
X4043M8Z-2.7A)
X4045P Z AN
X4045PZ-2.7A (Note)
(No longer available,
recommended replacement:
X4045S8Z-2.7A)
0 to 70 8 Ld PDIP (Pb-free)
X4043P Z AP
X4043PIZ-2.7A (Note)
(No longer available,
recommended replacement:
X4043M8IZ-2.7A)
X4045P Z AP
X4045PIZ-2.7A (Note)
(No longer available,
recommended replacement:
X4045S8IZ-2.7A)
-40 to 85 8 Ld PDIP (Pb-free)
X4043S8Z-2.7* (Note)
X4043 Z F
X4045S8Z-2.7* (Note)
X4045 Z F
2.7-5.5 2.55-2.7 0 to 70 8 Ld SOIC (Pb-free)
X4043S8IZ-2.7 (Note)
X4043 Z G
X4045S8IZ-2.7 (Note)
X4045 Z G
-40 to 85 8 Ld SOIC (Pb-free)
X4043M8Z-2.7 (Note)
DAX
DBF
X4045M8Z-2.7 (Note)
(No longer available,
recommended replacement:
X4045S8Z-2.7)
0 to 70 8 Ld MSOP (Pb-free)
X4043M8IZ-2.7(Note)
DAS
DBB
X4045M8IZ-2.7 (Note)
(No longer available,
recommended replacement:
X4045S8IZ-2.7)
-40 to 85 8 Ld MSOP (Pb-free)
X4043P Z F
X4043PZ-2.7 (Note)
(No longer available,
recommended replacement:
X4043M8Z-2.7)
X4045P Z F
X4045PZ-2.7 (Note)
(No longer available,
recommended replacement:
X4045S8Z-2.7)
0 to 70 8 Ld PDIP (Pb-free)
X4043P Z G
X4043PIZ-2.7 (Note)
(No longer available,
recommended replacement:
X4043M8IZ-2.7)
X4045P Z G
X4045PIZ-2.7 (Note)
(No longer available,
recommended replacement:
X4045S8IZ-2.7)
-40 to 85 8 Ld PDIP (Pb-free)
*Add "T1" suffix for tape and reel.
NOTE: Intersil Pb-free plus anneal products employ special Pb-free material sets; molding compounds/die attach materials and 100% matte tin plate
termination finish, which are RoHS compliant and compatible with both SnPb and Pb-free soldering operations. Intersil Pb-free products are MSL
classified at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.
3
FN8118.3
December 9, 2015
X4043, X4045
The memory portion of the device is a CMOS Serial
EEPROM array with Intersil’s block lock protection.
The array is internally organized as x 8. The device
features an 2-wire interface and software protocol
allowing operation on an I2C bus.
Write™
The device utilizes Intersil’s proprietary Direct
cell, providing a minimum endurance of 1,000,000
cycles and a minimum data retention of 100 years.
Pin
(SOIC/MSOP/DIP)
Name
1
NC
No internal connections
2
NC
No internal connections
3
RESET/RESET
PIN CONFIGURATION
8-Pin JEDEC SOIC, MSOP
(PDIP no longer available or supported)
NC
NC
RESET
VSS
1
2
3
4
8
7
6
5
VCC
WP
SCL
SDA
Function
Reset Output. RESET is an active LOW, open drain output which goes active
whenever VCC falls below VTRIP. It will remain active until VCC rises above the
VTRIP for tPURST. RESET/RESET goes active if the Watchdog Timer is enabled
and SDA remains either HIGH or LOW longer than the selectable Watchdog time
out period. RESET/RESET goes active on power-uppower-up and remains
active for 250ms after the power supply stabilizes. RESET is an active high open
drain output. An external pull up resistor is required on the RESET/RESET pin.
4
VSS
Ground
5
SDA
Serial Data. SDA is a bidirectional pin used to transfer data into and out of the
device. It has an open drain output and may be wire ORed with other open drain
or open collector outputs. This pin requires a pull up resistor and the input buffer
is always active (not gated).
6
SCL
Serial Clock. The Serial Clock input controls the serial bus timing for data input and
output.
7
WP
Write Protect. WP HIGH prevents writes to any location in the device (including
the control register). Connect WP pin to VSS when it is not used.
8
VCC
Supply Voltage
4
FN8118.3
December 9, 2015
X4043, X4045
PRINCIPLES OF OPERATION
Power-on Reset
Application of power to the X4043/45 activates a
Power-on Reset Circuit that pulls the RESET/RESET
pin active. This signal provides several benefits.
nonvolatile control bits in the status register determine
the watchdog timer period. The microprocessor can
change these watchdog bits, or they may be “locked”
by tying the WP pin HIGH.
Figure 1. Watchdog Restart
.6µs
– It prevents the system microprocessor from starting
to operate with insufficient voltage.
SCL
– It prevents the processor from operating prior to stabilization of the oscillator.
SDA
– It allows time for an FPGA to download its configuration prior to initialization of the circuit.
When VCC exceeds the device VTRIP threshold value
for
200ms
(nominal)
the
circuit
releases
RESET/RESET allowing the system to begin operation.
Low Voltage Monitoring
During operation, the X4043/45 monitors the VCC level
and asserts RESET/RESET if supply voltage falls
below a preset minimum VTRIP. The RESET/RESET
signal prevents the microprocessor from operating in a
power fail or brownout condition. The RESET/RESET
signal remains active until the voltage drops below 1V.
It also remains active until VCC returns and exceeds
VTRIP for 200ms.
Watchdog Timer
The Watchdog Timer circuit monitors the microprocessor activity by monitoring the SDA and SCL pins. A
standard read or write sequence to any slave address
byte restarts the watchdog timer and prevents the
(RESET/RESET) signal going active. A minimum
sequence to reset the watchdog timer requires four
microprocessor intructions namely, a Start, Clock Low,
Clock High and Stop. (See Page 18) The state of two
1.3µs
Start
WDT Reset
Stop
EEPROM Inadvertent Write Protection
When RESET/RESET goes active as a result of a low
voltage condition (VCC < VTRIP), any in-progress communications are terminated. While VCC < VTRIP, no new
communications are allowed and no nonvolatile write
operation can start. Nonvolatile writes in-progress when
RESET/RESET goes active are allowed to finish.
Additional protection mechanisms are provided with
memory block lock and the Write Protect (WP) pin.
These are discussed elsewhere in this document.
VTRIP Programming
The X4043/45 is shipped with a standard VCC threshold (VTRIP) voltage. This value will not change over
normal operating and storage conditions. However, in
applications where the standard VTRIP is not exactly
right, or if higher precision is needed in the VTRIP
value, the X4043/45 threshold may be adjusted. The
procedure is described below, and uses the application of a high voltage control signal.
Figure 2. Set VTRIP Level Sequence (VCC = desired VTRIP values WEL bit set)
VP = 15-18V
WP
0 1 2 3 4 5 6 7
0 1 2 3 4 5 6 7
0 1 2 3 4 5 6 7
SCL
SDA
A0h
5
01h
00h
FN8118.3
December 9, 2015
X4043, X4045
Setting a VTRIP Voltage
CASE B
There are two procedures used to set the threshold
voltages (VTRIP), depending if the threshold voltage to
be stored is higher or lower than the present value. For
example, if the present VTRIP is 2.9 V and the new
VTRIP is 3.2 V, the new voltage can be stored directly
into the VTRIP cell. If however, the new setting is to be
lower than the present setting, then it is necessary to
“reset” the VTRIP voltage before setting the new value.
Now if the VTRIP (actual), is higher than the VTRIP
(desired), perform the reset sequence as described in
the next section. The new VTRIP voltage to be applied to
VCC will now be: VTRIP (desired) - (VTRIP (actual) - VTRIP
(desired)).
Setting a Higher VTRIP Voltage
Setting a Lower VTRIP Voltage
To set a VTRIP threshold to a new voltage which is
higher than the present threshold, the user must apply
the desired VTRIP threshold voltage to the VCC. Then,
a programming voltage (Vp) must be applied to the
WP pin before a START condition is set up on SDA.
Next, issue on the SDA pin the Slave Address A0h,
followed by the Byte Address 01h for VTRIP and a 00h
Data Byte in order to program VTRIP . The STOP bit
following a valid write operation initiates the programming sequence. WP pin must then be brought LOW to
complete the operation.
To check if the VTRIP has been set, first power-down
the device. Slowly ramp up VCC and observe when the
output, RESET (4043) or RESET (4045) switches. The
voltage at which this occurs is the VTRIP (actual) (see
Figure 2).
Note: This operation does not corrupt the memory
array.
In order to set VTRIP to a lower voltage than the present value, then VTRIP must first be “reset” according to
the procedure described below. Once VTRIP has been
“reset”, then VTRIP can be set to the desired voltage
using the procedure described in “Setting a Higher
VTRIP Voltage”.
Resetting the VTRIP Voltage
To reset a VTRIP voltage, apply the programming voltage (Vp) to the WP pin before a START condition is
set up on SDA. Next, issue on the SDA pin the Slave
Address A0h followed by the Byte Address 03h followed by 00h for the Data Byte in order to reset VTRIP.
The STOP bit following a valid write operation initiates
the programming sequence. Pin WP must then be
brought LOW to complete the operation.
After being reset, the value of VTRIP becomes a nominal value of 1.7V or lesser.
CASE A
Now if the desired VTRIP is greater than the VTRIP
(actual), then add the difference between VTRIP
(desired) - VTRIP (actual) to the original VTRIP desired.
This is your new VTRIP that should be applied to VCC
and the whole sequence should be repeated again
(see Figure 5).
6
Note: This operation does not corrupt the memory
array.
FN8118.3
December 9, 2015
X4043, X4045
Figure 3. Reset VTRIP Level Sequence (VCC > 3V. WP = 15-18V, WEL bit set)
VP = 15-18V
WP
0 1 2 3 4 5 6 7
0 1 2 3 4 5 6 7
0 1 2 3 4 5 6 7
03h
00h
SCL
SDA
A0h
Figure 4. Sample VTRIP Reset Circuit
VP
Adjust
4.7K
RESET
VTRIP
Adj.
1
8
2
3 X4043
7
6
4
5
µC
Run
SCL
SDA
7
FN8118.3
December 9, 2015
X4043, X4045
Figure 5. VTRIP Programming Sequence
VTRIP Programming
No
Let: MDE = Maximum Desired Error
Desired
VTRIP <
Present Value ?
MDE+
Acceptable
Desired Value
YES
Error Range
Execute
VTRIP Reset Sequence
MDE–
Error = Actual – Desired
Set VCC = desired VTRIP
New VCC applied =
Old VCC applied + | Error |
Execute
Set Higher VTRIP Sequence
New VCC applied =
Old VCC applied – | Error |
Power-down
the Device
Execute Reset VTRIP
Sequence
Ramp VCC
NO
Output Switches?
(RESET)
YES
Error < MDE–
Error > MDE+
Actual VTRIP –
Desired VTRIP
= Error
| Error | < | MDE |
DONE
Control Register
The control register provides the user a mechanism for
changing the block lock and watchdog timer settings.
The block lock and watchdog timer bits are nonvolatile
and do not change when power is removed.
The user must issue a stop after sending this byte to
the register to initiate the nonvolatile cycle that stores
WD1, WD0, BP2, BP1, and BP0. The X4043/45 will
not acknowledge any data bytes written after the first
byte is entered.
The control register is accessed with a special preamble in the slave byte (1011) and is located at address
1FFh. It can only be modified by performing a byte
write operation directly to the address of the register
and only one data byte is allowed for each register
write operation. Prior to writing to the control register,
the WEL and RWEL bits must be set using a two step
process, with the whole sequence requiring 3 steps.
See "Writing to the Control Register".
8
FN8118.3
December 9, 2015
X4043, X4045
The state of the control register can be read at any time
by performing a random read at address 1FFh, using
the special preamble. Only one byte is read by each
register read operation. The X4043/45 resets itself after
the first byte is read. The master should supply a stop
condition to be consistent with the bus protocol, but a
stop is not required to end this operation.
WD1, WD0: Watchdog Timer Bits
The bits WD1 and WD0 control the period of the
watchdog timer. The options are shown below.
WD1
WD0
Watchdog Time Out Period
0
0
1.4 seconds
0
1
600 milliseconds
7
6
5
4
3
2
1
0
1
0
200 milliseconds
0
WD1
WD0
BP1
BP0
RWEL
WEL
BP2
1
1
Disabled (factory setting)
RWEL: Register Write Enable Latch (Volatile)
Writing to the Control Register
The RWEL bit must be set to “1” prior to a write to the
Control Register.
Changing any of the nonvolatile bits of the control register requires the following steps:
WEL: Write Enable Latch (Volatile)
– Write a 02H to the control register to set the write
enable latch (WEL). This is a volatile operation, so
there is no delay after the write. (Operation preceeded by a start and ended with a stop).
The WEL bit controls the access to the memory and to
the Register during a write operation. This bit is a volatile latch that powers up in the LOW (disabled) state.
While the WEL bit is LOW, writes to any address,
including any control registers will be ignored (no
acknowledge will be issued after the Data Byte). The
WEL bit is set by writing a “1” to the WEL bit and
zeroes to the other bits of the control register. Once
set, WEL remains set until either it is reset to 0 (by
writing a “0” to the WEL bit and zeroes to the other bits
of the control register) or until the part powers up
again. Writes to the WEL bit do not cause a nonvolatile
write cycle, so the device is ready for the next operation immediately after the stop condition.
BP2, BP1, BP0: Block Protect Bits (Nonvolatile)
BP2
BP1
BP0
The block protect bits, BP2, BP1 and BP0, determine
which blocks of the array are write protected. A write to
a protected block of memory is ignored. The block protect bits will prevent write operations to one of eight
segments of the array.
Protected Addresses
(Size)
0
0
0
None (factory setting)
None
0
0
1
180h - 1FFh (128 bytes)
Upper 1/4 (Q4)
0
1
0
100h - 1FFh (256 bytes)
Upper 1/2 (Q3,Q4)
0
1
1
000h - 1FFh (512 bytes)
Full Array (All)
1
0
0
000h - 00Fh (16 bytes)
First Page (P1)
1
0
1
000h - 01Fh (32 bytes)
First 2 pgs (P2)
1
1
0
000h - 03Fh (64 bytes)
First 4 pgs (P4)
1
1
1
000h - 07Fh (128 bytes)
First 8 pgs (P8)
9
Array Lock
– Write a 06H to the control register to set both the
register write enable latch (RWEL) and the WEL bit.
This is also a volatile cycle. The zeros in the data
byte are required. (Operation preceeded by a start
and ended with a stop).
– Write a value to the control register that has all the
control bits set to the desired state. This can be represented as 0xys t01r in binary, where xy are the
WD bits, and rst are the BP bits. (Operation preceeded by a start and ended with a stop). Since this
is a nonvolatile write cycle it will take up to 10ms to
complete. The RWEL bit is reset by this cycle and
the sequence must be repeated to change the nonvolatile bits again. If bit 2 is set to ‘1’ in this third step
(0xys t11r) then the RWEL bit is set, but the WD1,
WD0, BP2, BP1 and BP0 bits remain unchanged.
Writing a second byte to the control register is not
allowed. Doing so aborts the write operation and
returns a NACK.
– A read operation occurring between any of the previous operations will not interrupt the register write
operation.
– The RWEL bit cannot be reset without writing to the
nonvolatile control bits in the control register, power
cycling the device or attempting a write to a write
protected block.
To illustrate, a sequence of writes to the device consisting of [02H, 06H, 02H] will reset all of the nonvolatile bits in the control register to 0. A sequence of [02H,
06H, 06H] will leave the nonvolatile bits unchanged
and the RWEL bit remains set.
FN8118.3
December 9, 2015
X4043, X4045
SERIAL INTERFACE
Serial Interface Conventions
The device supports a bidirectional bus oriented protocol. The protocol defines any device that sends data
onto the bus as a transmitter, and the receiving device
as the receiver. The device controlling the transfer is
called the master and the device being controlled is
called the slave. The master always initiates data
transfers, and provides the clock for both transmit and
receive operations. Therefore, the devices in this family operate as slaves in all applications.
Serial Clock and Data
Data states on the SDA line can change only during
SCL LOW. SDA state changes during SCL HIGH are
reserved for indicating start and stop conditions. See
Figure 6.
Figure 6. Valid Data Changes on the SDA Bus
SCL
SDA
Data Stable
Data Change
Data Stable
Serial Start Condition
Serial Stop Condition
All commands are preceded by the start condition,
which is a HIGH to LOW transition of SDA when SCL
is HIGH. The device continuously monitors the SDA
and SCL lines for the start condition and will not
respond to any command until this condition has been
met. See Figure 7.
All communications must be terminated by a stop condition, which is a LOW to HIGH transition of SDA when
SCL is HIGH. The stop condition is also used to place
the device into the standby power mode after a read
sequence. A stop condition can only be issued after the
transmitting device has released the bus. See Figure 6.
Figure 7. Valid Start and Stop Conditions
SCL
SDA
Start
Serial Acknowledge
Acknowledge is a software convention used to indicate successful data transfer. The transmitting device,
either master or slave, will release the bus after transmitting eight bits. During the ninth clock cycle, the
receiver will pull the SDA line LOW to acknowledge
that it received the eight bits of data. Refer to Figure 8.
The device will respond with an acknowledge after
recognition of a start condition and if the correct device
identifier and select bits are contained in the slave
address byte. If a write operation is selected, the
device will respond with an acknowledge after the
receipt of each subsequent eight bit word. The device
10
Stop
will acknowledge all incoming data and address bytes,
except for the slave address byte when the device
identifier and/or select bits are incorrect.
In the read mode, the device will transmit eight bits of
data, release the SDA line, then monitor the line for an
acknowledge. If an acknowledge is detected and no
stop condition is generated by the master, the device
will continue to transmit data. The device will terminate
further data transmissions if an acknowledge is not
detected. The master must then issue a stop condition
to return the device to standby mode and place the
device into a known state.
FN8118.3
December 9, 2015
X4043, X4045
Figure 8. Acknowledge Response From Receiver
SCL from
Master
1
8
9
Data Output
from Transmitter
Data Output
from Receiver
Start
Acknowledge
Operational Notes
X4043/45 ADDRESSING
The device powers-up in the following state:
Slave Address Byte
Following a start condition, the master must output a
slave address byte. This byte consists of several parts:
– a device type identifier that is ‘1010’ to access the
array and ‘1011’ to access the control register.
– The WEL bit is set to ‘0’. In this state it is not possible to write to the device.
– SDA pin is the input mode.
– RESET signal is active for tPURST.
– two bits of ‘0’.
– one bit that becomes the MSB of the address.
– one bit of the slave command byte is a R/W bit. The
R/W bit of the slave address byte defines the operation to be performed. When the R/W bit is a one,
then a read operation is selected. A zero selects a
write operation. Refer to Figure 8.
– After loading the entire slave address byte from the
SDA bus, the device compares the input slave byte
data to the proper slave byte. Upon a correct compare,
the device outputs an acknowledge on the SDA line.
Word Address
The word address is either supplied by the master or
obtained from an internal counter. The internal counter
is undefined on a power-up condition.
Slave Address Byte
Slave Byte
1
0
1
0
SERIAL WRITE OPERATIONS
Byte Write
For a write operation, the device requires the slave
address byte and a word address byte. This gives the
master access to any one of the words in the array.
After receipt of the word address byte, the device
responds with an acknowledge, and awaits the next
eight bits of data. After receiving the 8 bits of the data
byte, the device again responds with an acknowledge.
The master then terminates the transfer by generating a
stop condition, at which time the device begins the internal write cycle to the nonvolatile memory. During this
internal write cycle, the device inputs are disabled, so the
device will not respond to any requests from the master.
The SDA output is at high impedance. See Figure 10.
A write to a protected block of memory will suppress
the acknowledge bit.
Figure 9. X4043/45 Addressing
Array
Control Reg.
– The device is in the low power standby state.
1
1
0
1
0
0
A8
R/W
A5
A4
A3
A2
A1
A0
Word Address
A7
A6
11
FN8118.3
December 9, 2015
X4043, X4045
Figure 10. Byte Write Sequence
Signals from
the Master
S
t
a
r
t
Byte
Address
Slave
Address
SDA Bus
S
t
o
p
Data
0
A
C
K
Signals from
the Slave
Page Write
The device is capable of a page write operation. It is
initiated in the same manner as the byte write operation; but instead of terminating the write cycle after the
first data byte is transferred, the master can transmit
an unlimited number of 8-bit bytes. After the receipt of
each byte, the device will respond with an acknowledge, and the address is internally incremented by
one. The page address remains constant. When the
counter reaches the end of the page, it “rolls over” and
A
C
K
A
C
K
goes back to ‘0’ on the same page. This means that
the master can write 16 bytes to the page starting at
any location on that page. If the master begins writing
at location 10, and loads 12 bytes, then the first 5
bytes are written to locations 10 through 15, and the
last 7 bytes are written to locations 0 through 6. Afterwards, the address counter would point to location 7 of
the page that was just written. If the master supplies
more than 16 bytes of data, then new data over-writes
the previous data, one byte at a time.
Figure 11. Page Write Operation
S
t
a
r
t
Signals from
the Master
SDA Bus
(1  n 16)
Slave
Address
S
t
o
p
Data
(n)
Data
(1)
Byte
Address
0
A
C
K
Signals from
the Slave
A
C
K
A
C
K
A
C
K
Figure 12. Writing 12-bytes to a 16-byte page starting at location 10
5 Bytes
7 Bytes
Address
=6
Address Pointer
Ends Here
Addr = 7
The master terminates the data byte loading by issuing a stop condition, which causes the device to begin
the nonvolatile write cycle. As with the byte write operation, all inputs are disabled until completion of the internal write cycle. See Figure 11 for the address,
acknowledge, and data transfer sequence.
12
Address
10
Address
n-1
Stops and Write Modes
Stop conditions (that terminate write operations) must
be sent by the master after sending at least 1 full data
byte, plus the subsequent ACK signal. If a stop is
issued in the middle of a data byte, or before 1 full data
byte plus its associated ACK is sent, then the device
will reset itself without performing the write. The contents of the array will not be effected.
FN8118.3
December 9, 2015
X4043, X4045
Figure 13. Acknowledge Polling Sequence
Acknowledge Polling
The disabling of the inputs during nonvolatile cycles
can be used to take advantage of the typical 5kHz
write cycle time. Once the stop condition is issued to
indicate the end of the master’s byte load operation,
the device initiates the internal nonvolatile cycle.
Acknowledge polling can be initiated immediately. To
do this, the master issues a start condition followed by
the slave address byte for a write or read operation. If
the device is still busy with the nonvolatile cycle then
no ACK will be returned. If the device has completed
the write operation, an ACK will be returned and the
host can then proceed with the read or write operation.
Refer to the flow chart in Figure 13.
Byte Load Completed
by Issuing STOP.
Enter ACK Polling
Issue START
Issue Slave Address
Byte (Read or Write)
ACK
Returned?
Serial Read Operations
Read operations are initiated in the same manner as
write operations with the exception that the R/W bit of
the slave address byte is set to one. There are three
basic read operations: Current Address Reads, Random Reads, and Sequential Reads.
NO
YES
Nonvolatile Cycle
Complete. Continue
Command
Current Address Read
NO
Issue STOP
YES
Internally the device contains an address counter that
maintains the address of the last word read incremented by one. Therefore, if the last read was to
address n, the next read operation would access data
from address n+1. On power-up, the address of the
address counter is undefined, requiring a read or write
operation for initialization.
Upon receipt of the slave address byte with the R/W bit
set to one, the device issues an acknowledge and then
transmits the eight bits of the data byte. The master terminates the read operation when it does not respond
with an acknowledge during the ninth clock and then
issues a stop condition. Refer to Figure 13 for the
address, acknowledge, and data transfer sequence.
Issue STOP
Continue Normal Read
or Write Command
Sequence
PROCEED
It should be noted that the ninth clock cycle of the read
operation is not a “don’t care.” To terminate a read
operation, the master must either issue a stop condition during the ninth cycle or hold SDA HIGH during
the ninth clock cycle and then issue a stop condition.
Figure 14. Current Address Read Sequence
Signals from
the Master
SDA Bus
Signals from
the Slave
13
S
t
a
r
t
S
t
o
p
Slave
Address
1
A
C
K
Data
FN8118.3
December 9, 2015
X4043, X4045
Random Read
Random read operation allows the master to access
any memory location in the array. Prior to issuing the
slave address byte with the R/W bit set to one, the
master must first perform a “dummy” write operation.
The master issues the start condition and the slave
address byte, receives an acknowledge, then issues
the word address bytes. After acknowledging receipts
of the word address bytes, the master immediately
issues another start condition and the slave address
byte with the R/W bit set to one. This is followed by an
acknowledge from the device and then by the eight bit
word. The master terminates the read operation by not
responding with an acknowledge and then issuing a
stop condition. Refer to Figure 15 for the address,
acknowledge, and data transfer sequence.
Figure 15. Random Address Read Sequence
S
t
a
r
t
Signals from
the Master
SDA Bus
S
t
a
r
t
Byte
Address
Slave
Address
1
0
A
C
K
Signals from
the Slave
S
t
o
p
Slave
Address
A
C
K
There is a similar operation, called “Set Current
Address” where the device does no operation, but
enters a new address into the address counter if a
stop is issued instead of the second start shown in Figure 14. The device goes into standby mode after the
stop and all bus activity will be ignored until a start is
detected. The next current address read operation
reads from the newly loaded address. This operation
could be useful if the master knows the next address it
needs to read, but is not ready for the data.
Sequential Read
Sequential reads can be initiated as either a current
address read or random address read. The first data
byte is transmitted as with the other modes; however,
A
C
K
Data
the master now responds with an acknowledge, indicating it requires additional data. The device continues to
output data for each acknowledge received. The master
terminates the read operation by not responding with an
acknowledge and then issuing a stop condition.
The data output is sequential, with the data from address
n followed by the data from address n + 1. The address
counter for read operations increments through all page
and column addresses, allowing the entire memory contents to be serially read during one operation. At the end
of the address space the counter “rolls over” to address
0000H and the device continues to output data for each
acknowledge received. Refer to Figure 16 for the
acknowledge and data transfer sequence.
Figure 16. Sequential Read Sequence
Signals from
the Master
Slave
Address
SDA Bus
1
A
C
K
A
C
K
Signals from
the Slave
Data
(1)
A
C
K
Data
(2)
S
t
o
p
A
C
K
Data
(n-1)
Data
(n)
(n is any integer greater than 1)
14
FN8118.3
December 9, 2015
X4043, X4045
Symbol Table
Data Protection
The following circuitry has been included to prevent
inadvertent writes:
INPUTS
OUTPUTS
Must be
steady
Will be
steady
May change
from LOW
to HIGH
Will change
from LOW
to HIGH
May change
from HIGH
to LOW
Will change
from HIGH
to LOW
– The WP pin, when held HIGH, prevents all writes to
the array and the control register.
Don’t Care:
Changes
Allowed
Changing:
State Not
Known
– Communication to the device is inhibited as a result
of a low voltage condition (VCC < VTRIP)any in-progress communication is terminated.
N/A
Center Line
is High
Impedance
– The WEL bit must be set to allow write operations.
– The proper clock count and bit sequence is required
prior to the stop bit in order to start a nonvolatile
write cycle.
– A three step sequence is required before writing into
the control register to change watchdog timer or
block lock settings.
WAVEFORM
– Block lock bits can protect sections of the memory
array from write operations.
15
FN8118.3
December 9, 2015
X4043, X4045
ABSOLUTE MAXIMUM RATINGS
COMMENT
Temperature under bias .................... -65°C to +135°C
Storage temperature ......................... -65°C to +150°C
Voltage on any pin with
respect to VSS ...................................... -1.0V to +7V
D.C. output current ............................................... 5mA
Lead temperature (soldering, 10 seconds) ........ 300°C
Stresses above those listed under “Absolute Maximum
Ratings” may cause permanent damage to the device.
This is a stress rating only; the functional operation of the
device (at these or any other conditions above those
listed in the operational sections of this specification) is
not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
RECOMMENDED OPERATING CONDITIONS
Temperature
Commercial
Industrial
Min.
0°C
-40°C
Max.
70°C
+85°C
Option
-2.7 and -2.7A
Blank and -4.5A
Supply Voltage Limits
2.7V to 5.5V
4.5V to 5.5V
D.C. OPERATING CHARACTERISTICS (Over the recommended operating conditions unless otherwise specified.)
VCC = 2.7 to 5.5V
Max.
Unit
Active supply current read
1.0
mA
Active supply current write
3.0
mA
Standby current AC (WDT off)
1
µA
VIL = VCC x 0.1, VIH = VCC x 0.9
fSCL= 400kHz, SDA = open
VCC = 1.22 x VCC min
ISB2(2)
Standby current DC (WDT off)
1
µA
VSDA = VSCL = VSB
Others = GND or VSB
ISB3(2)
Standby current DC (WDT on)
20
µA
VSDA =VSCL = VSB
Others = GND or VSB
ILI
Input leakage current
10
µA
VIN = GND to VCC
ILO
Output leakage current
10
µA
VSDA = GND to VCC
device is in standby
-0.5
VCC x 0.3
V
VCC + 0.5
V
Symbol
ICC1
(1)
ICC2
(1)
(2)
ISB1
Parameter
Min.
VIL(3)
Input LOW voltage
VIH(3)
Input nonvolatile
VCC x 0.7
VHYS
Schmitt trigger input hysteresis
Fixed input level
VCC related level
0.2
.05 x VCC
VOL
Output LOW voltage
Test Conditions
VIL = VCC x 0.1, VIH = VCC x 0.9
fSCL = 400kHz
V
V
0.4
V
IOL = 3.0mA (2.7-5.5V)
IOL = 1.8mA (2.0-3.6V)
Notes: (1) The device enters the active state after any start, and remains active until: 9 clock cycles later if the device select bits in the slave
address byte are incorrect; 200ns after a stop ending a read operation; or tWC after a stop ending a write operation.
(2) The device goes into standby: 200ns after any stop, except those that initiate a nonvolatile write cycle; tWC after a stop that initiates a
nonvolatile cycle; or 9 clock cycles after any start that is not followed by the correct device select bits in the slave address byte.
(3) VIL min. and VIH max. are for reference only and are not tested.
16
FN8118.3
December 9, 2015
X4043, X4045
CAPACITANCE (TA = 25°C, f = 1.0 MHz, VCC = 5V)
Symbol
COUT
(4)
CIN(4)
Parameter
Max.
Unit
Test Conditions
Output capacitance (SDA, RESET/RESET)
8
pF
VOUT = 0V
Input capacitance (SCL, WP)
6
pF
VIN = 0V
Notes: (4) This parameter is periodically sampled and not 100% tested.
EQUIVALENT A.C. LOAD CIRCUIT
A.C. TEST CONDITIONS
5V
5V
1533
For VOL= 0.4V
and IOL = 3 mA
SDA
4.6k
Input pulse levels
0.1 VCC to 0.9 VCC
Input rise and fall times
10ns
Input and output timing levels
0.5 VCC
Output load
Standard output load
RESET
100pF
100pF
A.C. CHARACTERISTICS (Over recommended operating conditions, unless otherwise specified)
100kHz
Symbol
fSCL
Parameter
SCL clock frequency
400kHz
Min.
Max.
Min.
Max.
Unit
0
100
0
400
kHz
tIN
Pulse width suppression time at inputs
n/a
n/a
50
tAA
SCL LOW to SDA data out valid
0.1
0.9
0.1
tBUF
Time the bus free before start of new transmission
4.7
1.3
µs
tLOW
Clock LOW time
4.7
1.3
µs
tHIGH
Clock HIGH time
4.0
0.6
µs
tSU:STA
Start condition setup time
4.7
0.6
µs
tHD:STA
Start condition hold time
4.0
0.6
µs
tSU:DAT
Data in setup time
250
100
ns
tHD:DAT
Data in hold time
5.0
0
µs
tSU:STO
Stop condition setup time
0.6
0.6
µs
Data output hold time
50
50
ns
tDH
ns
0.9
µs
.1Cb(6)
300
ns
300
ns
tR
SDA and SCL rise time
1000
20 +
tF
SDA and SCL fall time
300
20 + .1Cb(6)
tSU:WP
WP setup time
0.4
0.6
s
tHD:WP
WP hold time
0
0
s
Cb
Capacitive load for each bus line
400
400
pF
Notes: (5) Typical values are for TA = 25°C and VCC = 5.0V
(6) Cb = total capacitance of one bus line in pF.
17
FN8118.3
December 9, 2015
X4043, X4045
TIMING DIAGRAMS
Bus Timing
tHIGH
tF
SCL
tLOW
tR
tSU:DAT
tSU:STA
tHD:DAT
tHD:STA
SDA IN
tSU:STO
tAA
tDH
tBUF
SDA OUT
WP Pin Timing
START
SCL
Clk 1
Clk 9
Slave Address Byte
SDA IN
tSU:WP
tHD:WP
WP
Write Cycle Timing
SCL
SDA
8th Bit of Last Byte
ACK
tWC
Stop
Condition
Start
Condition
Nonvolatile Write Cycle Timing
Symbol
tWC
(7)
Parameter
Write cycle time
Min.
Typ.(7)
Max.
Unit
5
10
ms
Notes: (7) tWC is the time from a valid stop condition at the end of a write sequence to the end of the self-timed internal nonvolatile write cycle. It is
the minimum cycle time to be allowed for any nonvolatile write by the user, unless acknowledge polling is used.
18
FN8118.3
December 9, 2015
X4043, X4045
Power-Up and Power-Down Timing
VTRIP
VCC
tPURST
0 Volts
tR
tPURST
tF
tRPD
VRVALID
RESET
(X4043)
VRVALID
RESET
(X4045)
RESET Output Timing
Symbol
Min.
Typ.
Max.
Unit
VTRIP
Reset trip point voltage, X4043/45-4.5A
Reset trip point voltage, X4043/45
Reset trip point voltage, X4043/45-2.7A
Reset trip point voltage, X4043/45-2.7
4.5
4.25
2.85
2.55
4.62
4.38
2.92
2.62
4.75
4.5
3.0
2.7
V
tPURST
Power-up reset time out
100
200
400
ms
10
20
tRPD
(8)
Parameter
VCC detect to RESET/RESET
µs
tF(8)
VCC fall time
20
mV/µs
tR(8)
VCC rise time
20
mV/µs
Reset valid VCC
1
V
VRVALID
tWDO
Watchdog time out period,
WD1 = 1, WD0 = 0
WD1 = 0, WD0 = 1
WD1 = 0, WD0 = 0
tRSP
Watchdog Time Restart pulse width
tRST
Reset time out
100
450
1
200
600
1.4
300
800
2
1
100
ms
ms
sec
µs
200
400
ms
Notes: (8) This parameter is periodically sampled and not 100% tested.
19
FN8118.3
December 9, 2015
X4043, X4045
Watchdog Time Out For 2-Wire Interface
Start
Clockin (0 or 1)
tRSP
Start
< tWDO
SCL
SDA
tRST
(4043) RESET
tWDO
tRST
WDT
Restart
Start
Minimum Sequence to Reset WDT
SCL
SDA
VTRIP Set/Reset Conditions
VCC
(VTRIP)
tTHD
VP
tTSU
WP
tVPS
tVPH
SCL
7
0
0
7
0
tVPO
7
SDA
A0h
Start
01h* sets VTRIP
03h* resets VTRIP
00h
tWC
* all others reserved
20
FN8118.3
December 9, 2015
X4043, X4045
VTRIP Programming Specifications: VCC = 2.0-5.5V; Temperature = 25°C
Parameter
Description
Min.
Max.
Unit
tVPS
WP Program Voltage Setup time
10
µs
tVPH
WP Program Voltage Hold time
10
µs
tTSU
VTRIP Level Setup time
10
µs
tTHD
VTRIP Level Hold (stable) time
10
µs
tWC
VTRIP Program Cycle
10
ms
tVPO
Program Voltage Off time before next cycle
1
ms
Programming Voltage
15
18
V
VTRIP Set Voltage Range
2.0
4.75
V
Vtv
VTRIP Set Voltage variation after programming (-40 to +85°C).
-25
+25
mV
tVPS
WP Program Voltage Setup time
10
VP
VTRAN
µs
REVISION HISTORY
The revision history provided is for informational purposes only and is believed to be accurate, but not warranted. Please go to the web to make sure that
you have the latest revision.
DATE
REVISION
December 9, 2015
FN8118.3
CHANGE
Updated Ordering Information Table on page 2.
Added Revision History and About Intersil sections.
ABOUT INTERSIL
Intersil Corporation is a leading provider of innovative power management and precision analog solutions. The company's products
address some of the largest markets within the industrial and infrastructure, mobile computing and high-end consumer markets.
For the most updated datasheet, application notes, related documentation and related parts, please see the respective product
information page found at www.intersil.com.
You may report errors or suggestions for improving this datasheet by visiting www.intersil.com/ask.
Reliability reports are also available from our website at www.intersil.com/support
21
FN8118.3
December 9, 2015
X4043, X4045
PACKAGING INFORMATION
8-Lead Plastic Small Outline Gull Wing Package Type S
0.150 (3.80) 0.228 (5.80)
0.158 (4.00) 0.244 (6.20)
Pin 1 Index
Pin 1
0.014 (0.35)
0.019 (0.49)
0.188 (4.78)
0.197 (5.00)
(4X) 7°
0.053 (1.35)
0.069 (1.75)
0.004 (0.19)
0.010 (0.25)
0.050 (1.27)
0.010 (0.25)
X 45°
0.020 (0.50)
0.050" Typical
0.050"
Typical
0° - 8°
0.0075 (0.19)
0.010 (0.25)
0.250"
0.016 (0.410)
0.037 (0.937)
FOOTPRINT
0.030"
Typical
8 Places
NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)
22
FN8118.3
December 9, 2015
X4043, X4045
PACKAGING INFORMATION
8-Lead Miniature Small Outline Gull Wing Package Type M
0.118 ± 0.002
(3.00 ± 0.05)
0.012 + 0.006 / -0.002
(0.30 + 0.15 / -0.05)
0.0256 (0.65) Typ.
R 0.014 (0.36)
0.118 ± 0.002
(3.00 ± 0.05)
0.030 (0.76)
0.0216 (0.55)
0.036 (0.91)
0.032 (0.81)
0.040 ± 0.002
(1.02 ± 0.05)
7° Typ.
0.008 (0.20)
0.004 (0.10)
0.0256" Typical
0.150 (3.81)
Ref.
0.193 (4.90)
Ref.
0.007 (0.18)
0.005 (0.13)
0.025"
Typical
0.220"
FOOTPRINT
0.020"
Typical
8 Places
NOTE:
1. ALL DIMENSIONS IN INCHES AND (MILLIMETERS)
23
FN8118.3
December 9, 2015
X4043, X4045
PACKAGING INFORMATION
8-Lead Plastic Dual In-Line Package Type P
0.430 (10.92)
0.360 (9.14)
0.260 (6.60)
0.240 (6.10)
Pin 1 Index
Pin 1
0.300
(7.62) Ref.
Half Shoulder Width On
All End Pins Optional
0.145 (3.68)
0.128 (3.25)
Seating
Plane
0.025 (0.64)
0.015 (0.38)
0.065 (1.65)
0.045 (1.14)
0.150 (3.81)
0.125 (3.18)
0.110 (2.79)
0.090 (2.29)
.073 (1.84)
Max.
Typ. 0.010 (0.25)
0.060 (1.52)
0.020 (0.51)
0.020 (0.51)
0.016 (0.41)
0.325 (8.25)
0.300 (7.62)
0°
15°
NOTE:
1. ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)
2. PACKAGE DIMENSIONS EXCLUDE MOLDING FLASH
All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9001 quality systems.
Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality
Intersil products are sold by description only. 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 data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and
reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
24
FN8118.3
December 9, 2015