DESCRIPTION
The CAT1026 and CAT1027 are complete memory and
supervisory solutions for microcontroller-based systems.
A 2k-bit serial EEPROM memory and a system power
supervisor with brown-out protection are integrated
together in low power CMOS technology. Memory
interface is via a 400kHz I
2
C bus.
The CAT1026 and CAT1027 provide a precision V
CC
sense circuit with five reset threshold voltage options
that support 5V, 3.3V and 3V systems. The power
supply monitor and reset circuit protects memory and
systems controllers during power up/down and against
brownout conditions. If power supply voltages are out of
tolerance reset signals become active preventing the
system microcontroller, ASIC, or peripherals from
operating.
The CAT1026 features two open drain reset outputs:
one (RESET) drives high and the other (
RESET
) drives
low whenever V
CC
falls below the threshold. Reset
outputs become inactive typically 200 ms after the
supply voltage exceeds the reset threshold value. With
both active high and low reset signals, interface to
microcontrollers and other ICs is simple. CAT1027 has
only a
RESET
output. In addition, the
RESET
pin can be
CAT1026, CAT1027
Dual Voltage Supervisory Circuits with I
2
C Serial 2k-bit CMOS EEPROM
FEATURES
s
Precision V
CC
power supply voltage monitor
-- 5V, 3.3 V and 3 V systems
-- Five threshold voltage options
s
Additional voltage monitoring
-- Externally adjustable down to 1.25 V
s
Watchdog timer (CAT1027 only)
s
Active high or low reset
-- Valid reset guaranteed to V
CC
= 1 V
s
400 kHz I
2
C bus
s
2.7 V to 5.5 V operation
s
Low power CMOS technology
s
16-Byte page write buffer
s
Built-in inadvertent write protection
s
1,000,000 Program/Erase cycles
s
Manual reset capability
s
100 year data retention
s
8-pin DIP, SOIC, TSSOP, MSOP or TDFN
(3 x 4.9 mm & 3 x 3 mm foot-print) packages
-- TDFN max height is 0.8mm
s
Industrial and extended temperature ranges
2004 by Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
Doc No. 3010, Rev. H
used as an input for push-button manual reset capability.
The CAT1026 and CAT1027 provide an auxiliary voltage
sensor input, V
SENSE
, which is used to monitor a second
system supply. The auxiliary high impedance comparator
drives the open drain output, V
LOW
, whenever the sense
voltage is below 1.25V threshold.
The CAT1027 is designed with a 1.6 second watchdog timer
circuit that resets a system to a known state if software or a
hardware glitch halts or "hangs" the system. The CAT1027
features a watchdog timer interrupt input, WDI.
The on-chip 2k-bit EEPROM memory features a 16-byte
page. In addition, hardware data protection is provided by a
V
CC
sense circuit that prevents writes to memory whenever
V
CC
falls below the reset threshold or until V
CC
reaches the
reset threshold during power up.
Available packages include 8-pin DIP and surface mount,
8-pin SO, 8-pin TSSOP, 8-pin TDFN and 8-pin MSOP
packages. The TDFN package thickness is 0.8mm
maximum. TDFN footprint options are 3x3mm or 3x4.9mm
(MSOP pad layout).
HA
LOGEN FREE
TM
LEAD FREE
2
CAT1026, CAT1027
Doc. No. 3010, Rev. H
Part Dash Minimum
Maximum
Number Threshold
Threshold
-45
4.50
4.75
-42
4.25
4.50
-30
3.00
3.15
-28
2.85
3.00
-25
2.55
2.70
RESET Threshold Options
BLOCK DIAGRAM
PIN CONFIGURATION
(Bottom View)
TDFN Package: 3mm x 4.9mm
0.8mm maximum height - (RD2, ZD2)
(Bottom View)
TDFN Package: 3mm x 3mm
0.8mm maximum height - (RD4, ZD4)
VLOW
VCC
RESET
SCL
SDA
RESET
VSENSE
VSS
CAT1026
1
2
3
4
8
7
6
5
VCC
WDI
SCL
SDA
CAT1027
1
2
3
4
8
7
6
5
VLOW
RESET
VSENSE
VSS
1
2
3
4
8
7
6
5
VCC
RESET
SCL
SDA
CAT1026
VLOW
RESET
VSENSE
VSS
1
2
3
4
8
7
6
5
VCC
WDI
SCL
SDA
CAT1027
VLOW
RESET
VSENSE
VSS
1
2
3
4
8
7
6
5
VCC
RESET
SCL
SDA
VLOW
RESET
VSENSE
VSS
CAT1026
1
2
3
4
8
7
6
5
VCC
WDI
SCL
SDA
CAT1027
VLOW
RESET
VSENSE
VSS
2kbit
DOUT
ACK
SENSE AMPS
SHIFT REGISTERS
CONTROL
LOGIC
WORD ADDRESS
BUFFERS
START/STOP
LOGIC
EEPROM
VCC
EXTERNAL LOAD
COLUMN
DECODERS
XDEC
DATA IN STORAGE
HIGH VOLTAGE/
TIMING CONTROL
VSS
SDA
RESET
Controller
STATE COUNTERS
SLAVE
ADDRESS
COMPARATORS
SCL
RESET
RESET
(CAT1026)
WDI
(CAT1027)
-
+
VCC
VSENSE
-
+
VREF
VLOW
VREF
Auxiliary Voltage Monitor
VCC Monitor
DIP Package (P, L)
SOIC Package (S, V)
TSSOP Package (U, Y)
MSOP Package (R, Z)
3
CAT1026, CAT1027
Doc No. 3010, Rev. H
PIN DESCRIPTION
RESET/
RESET
RESET
RESET
RESET
RESET:
RESET OUTPUTS
(RESET CAT1026 Only)
These are open drain pins and
RESET
can be used as a
manual reset trigger input. By forcing a reset condition on
the pin the device will initiate and maintain a reset condition.
The RESET pin must be connected through a pull-down
resistor, and the
RESET
pin must be connected through a
pull-up resistor.
SDA:
SERIAL DATA ADDRESS
The bidirectional serial data/address pin is used to transfer
all data into and out of the device. The SDA pin is an open
drain output and can be wire-ORed with other open drain
or open collector outputs.
SCL:
SERIAL CLOCK
Serial clock input.
V
SENSE
:
AUXILIARY VOLTAGE MONITOR INPUT
The V
SENSE
input is a second voltage monitor which
is compared against CAT1026 and CAT1027 internal
reference voltage of 1.25V typically. Whenever the
input voltage is lower than 1.25V, the open drain
VLOW output will be driven low. An external resistor
divider is used to set the voltage level to be sensed.
Connect V
SENSE
to V
CC
if unused.
V
LOW
:
AUXILIARY VOLTAGE MONITOR OUTPUT
This open drain output goes low when V
SENSE
is less
than 1.25V and goes high when V
SENSE
exceeds the
reference voltage.
WDI (CAT1027 Only):
WATCHDOG TIMER INTERRUPT
Watchdog Timer Interrupt Input is used to reset the
watchdog timer. If a transition from high to low or low to
high does not occur every 1.6 seconds, the RESET
outputs will be driven active.
CAT10XX FAMILY OVERVIEW
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2
For supervisory circuits with embedded 16k EEPROM, please refer to the CAT1161, CAT1162 and CAT1163
data sheets.
PIN FUNCTIONS
Pin Name
Function
RESET
Active Low Reset Input/Output
V
SS
Ground
SDA
Serial Data/Address
SCL
Clock Input
RESET
Active High Reset Output (CAT1026 only)
V
CC
Power Supply
V
SENSE
Auxiliary Voltage Monitor Input
V
LOW
Auxiliary Voltage Monitor Output
WDI
Watchdog Timer Interrupt (CAT1027 only)
OPERATING TEMPERATURE RANGE
Industrial
-40C to 85C
Extended
-40C to 125C
4
CAT1026, CAT1027
Doc. No. 3010, Rev. H
ABSOLUTE MAXIMUM RATINGS
Temperature Under Bias ................. 55
C to +125
C
Storage Temperature ....................... 65
C to +150
C
Voltage on any Pin with
Respect to Ground
(1)
........... 2.0 V to V
CC
+ 2.0 V
V
CC
with Respect to Ground ............ 2.0 V to + 7.0 V
Package Power Dissipation
Capability (T
A
= 25
C) .................................. 1.0 W
DC OPERATING CHARACTERISTICS
V
CC
= 2.7 V to 5.5 V and over the recommended temperature conditions unless otherwise specified.
Notes:
1.
V
IL
min and V
IH
max are reference values only and are not tested.
2.
This parameter is tested initially and after a design or process change that affects the parameter. Not 100% tested.
Lead Soldering Temperature (10 seconds) ...... 300
C
Output Short Circuit Current
(2)
........................ 100 mA
Stresses above those listed under "Absolute Maximum Ratings" may cause permanent damage
to the device. These are stress ratings only, and functional operation of the device at these or
any other conditions outside of those listed in the operational sections of this specification is not
implied. Exposure to any absolute maximum rating for extended periods may affect device
performance and reliability.
Note:
(1)
The minimum DC input voltage is 0.5V. During transitions, inputs may undershoot to
-2.0V for periods of less than 20 ns. Maximum DC voltage on output pins is
V
CC
+0.5 V, which may overshoot to V
CC
+2.0V for periods of less than 20 ns.
(2)
Output shorted for no more than one second. No more than one output shorted at a
time.
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CAT1026, CAT1027
Doc No. 3010, Rev. H
CAPACITANCE
T
A
= 25
C, f = 1.0 MHz, V
CC
= 5V
Symbol
Test
Test Conditions
Max
Units
C
OUT
(1)
Output Capacitance
V
OUT
= 0 V
8
pF
C
IN
(1)
Input Capacitance
V
IN
= 0 V
6
pF
AC CHARACTERISTICS
V
CC
= 2.7 V to 5.5 V and over the recommended temperature conditions, unless otherwise specified.
Notes:
1.
This parameter is characterized initially and after a design or process change that affects the parameter. Not 100% tested.
2.
Test Conditions according to "AC Test Conditions" table.
3.
The write cycle time is the time from a valid stop condition of a write sequence to the end of the internal program/erase cycle. During the
write cycle, the bus interface circuits are disabled, SDA is allowed to remain high and the device does not respond to its slave address.
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6
CAT1026, CAT1027
Doc. No. 3010, Rev. H
VOLTAGE MONITOR AND RESET CIRCUIT AC CHARACTERISTICS
Notes:
1.
Test Conditions according to "AC Test Conditions" table.
2.
Power-up, Input Reference Voltage V
CC
= V
TH
, Reset Output Reference Voltage and Load according to "AC Test Conditions" Table.
3.
Power-Down, Input Reference Voltage V
CC
= V
TH
, Reset Output Reference Voltage and Load according to "AC Test Conditions" Table.
4.
V
CC
Glitch Reference Voltage = V
THmin
; Based on characterization data.
5.
0 < V
SENSE
V
CC
, V
LOW
Output Reference Voltage and Load according to "AC Test Conditions" Table.
6.
This parameter is characterized initially and after a design or process change that affects the parameter. Not 100% tested.
7.
t
PUR
and t
PUW
are the delays required from the time V
CC
is stable until the specified memory operation can be initiated.
8.
Latch-up protection is provided for stresses up to 100mA on input and output pins from -1 V to V
CC
+ 1 V.
AC TEST CONDITIONS
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RELIABILITY CHARACTERISTICS
Symbol
Parameter
Reference Test Method
Min
Max
Units
N
END
(6)
Endurance
MIL-STD-883, Test Method 1033
1,000,000
Cycles/Byte
T
DR
(6)
Data Retention
MIL-STD-883, Test Method 1008
100
Years
V
ZAP
(6)
ESD Susceptibility
MIL-STD-883, Test Method 3015
2000
Volts
I
LTH
(6)(8)
Latch-Up
JEDEC Standard 17
100
mA
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7
CAT1026, CAT1027
Doc No. 3010, Rev. H
Data Protection
The CAT1026 and CAT1027 devices have been designed
to solve many of the data corruption issues that have long
been associated with serial EEPROMs. Data corruption
occurs when incorrect data is stored in a memory location
which is assumed to hold correct data.
Whenever the device is in a Reset condition, the embedded
EEPROM is disabled for all operations, including write
operations. If the Reset output(s) are active, in progress
communications to the EEPROM are aborted and no new
communications are allowed. In this condition an internal
write cycle to the memory can not be started, but an in
progress internal non-volatile memory write cycle can not
be aborted. An internal write cycle initiated before the
Reset condition can be successfully finished if there is
enough time (5ms) before VCC reaches the minimum
value of 2 V.
In addition, to avoid data corruption due to the loss of
power supply voltage during the memory internal write
operation, the system controller should monitor the
unregulated DC power. Using the second voltage sensor,
V
SENSE
, to monitor an unregulated power supply, the
CAT1026 and CAT1027 signals an impending power
failure by setting V
LOW
low.
Watchdog Timer
The Watchdog Timer provides an independent protection
for microcontrollers. During a system failure, the CAT1027
device will provide a reset signal after a time-out interval
of 1.6 seconds for a lack of activity. CAT1027 is designed
with the Watchdog timer feature on the WDI pin. If WDI
does not toggle within 1.6 second intervals, the reset
condition will be generated on reset output. The watchdog
timer is cleared by any transition on monitored line.
As long as reset signal is asserted, the watchdog timer
will not count and will stay cleared.
DEVICE OPERATION
Reset Controller Description
The CAT1026 and CAT1027 precision RESET
controllers ensure correct system operation during
brownout and power up/down conditions. They are
configured with open drain RESET outputs.
During power-up, the RESET outputs remain active
until V
CC
reaches the V
TH
threshold and will continue
driving the outputs for approximately 200 ms (t
PURST
)
after reaching V
TH
. After the t
PURST
timeout interval, the
device will cease to drive the reset outputs. At this point
the reset outputs will be pulled up or down by their
respective pull up/down resistors.
During power-down, the RESET outputs will be active
when V
CC
falls below V
TH
. The
RESET
output will be
valid so long as V
CC
is >1.0 V (V
RVALID
). The device is
designed to ignore the fast negative going V
CC
transient
pulses (glitches).
Reset output timing is shown in Figure 1.
Manual Reset Capability
The
RESET
pin can operate as reset output and manual
reset input. The input is edge triggered; that is, the
RESET
input will initiate a reset timeout after detecting
a high to low transition.
When
RESET
I/O is driven to the active state, the 200
msec timer will begin to time the reset interval. If external
reset is shorter than 200 ms, Reset outputs will remain
active at least 200 ms.
Monitoring Two Voltages
The CAT1026 and CAT1027 feature a second voltage
sensor, V
SENSE
, which drives the open drain V
LOW
output low whenever the input voltage is below 1.25 V.
The auxiliary voltage monitor timing is shown in Figure
2.
By using an external resistor divider the sense circuitry
can be set to monitor a second supply in the system.
The circuit shown in Figure 3 provides an externally
adjustable threshold voltage, V
TH_ADJ
to monitor the
auxiliary voltage. The low leakage current at V
SENSE
allows the use of large value resistors, to reduce the
system power consumption. The V
LOW
output can be
externally connected to the RESET output to generate
a reset condition when either of the supplies is invalid.
In other applications, V
LOW
signal can be used to
interrupt the system controller for an impending power
failure notification.
8
CAT1026, CAT1027
Doc. No. 3010, Rev. H
Figure 2. Auxiliary Voltage Monitor Timing
tRPD2
VLOW
tRPD2
tRPD2
tRPD2
VSENSE
VREF
VLOW
VSENSE
VAUX
R1
R2
Externally adjustable
threshold
VTH-ADJ
VTH-ADJ = VREF
R1 + R2
R2
= 1.25V
R1 + R2
R2
CAT1026/27
VCC
Power Fail
Interrupt
Figure 3. Auxiliary Voltage Monitor
Figure 1. RESET Output Timing
GLITCH
t
V
CC
PURST
t
PURST
t
RPD1
t
RVALID
V
V
TH
RESET
RESET
RPD1
t
9
CAT1026, CAT1027
Doc No. 3010, Rev. H
EMBEDDED EEPROM OPERATION
The CAT1026 and CAT1027 feature a 2kbit embedded
serial EEPROM that supports the I
2
C Bus data
transmission protocol. This Inter-Integrated Circuit Bus
protocol defines any device that sends data to the bus to
be a transmitter and any device receiving data to be a
receiver. The transfer is controlled by the Master device
which generates the serial clock and all START and
STOP conditions for bus access. Both the Master device
and Slave device can operate as either transmitter or
receiver, but the Master device controls which mode is
activated.
I
2
C Bus Protocol
The features of the I
2
C bus protocol are defined as
follows:
(1) Data transfer may be initiated only when the bus is
not busy.
(2) During a data transfer, the data line must remain
stable whenever the clock line is high. Any changes in
the data line while the clock line is high will be interpreted
as a START or STOP condition.
START Condition
The START Condition precedes all commands to the
device, and is defined as a HIGH to LOW transition of
SDA when SCL is HIGH. The CAT1026 and CAT1027
monitor the SDA and SCL lines and will not respond until
this condition is met.
STOP Condition
A LOW to HIGH transition of SDA when SCL is HIGH
determines the STOP condition. All operations must end
with a STOP condition.
DEVICE ADDRESSING
The Master begins a transmission by sending a START
condition. The Master sends the address of the particular
slave device it is requesting. The four most significant
bits of the 8-bit slave address are programmable in metal
and the default is 1010.
The last bit of the slave address specifies whether a
Read or Write operation is to be performed. When this bit
is set to 1, a Read operation is selected, and when set
to 0, a Write operation is selected.
After the Master sends a START condition and the slave
address byte, the CAT1026 and CAT1027 monitor the
bus and responds with an acknowledge (on the SDA
line) when its address matches the transmitted slave
address. The CAT1026 and CAT1027 then perform a
Read or Write operation depending on the R/
W
bit.
tHIGH
SCL
SDA IN
SDA OUT
tLOW
tF
tLOW
tR
tBUF
tSU:STO
tSU:DAT
tHD:DAT
tHD:STA
tSU:STA
tAA
tDH
Figure 4. Bus Timing
Figure 5. Write Cycle Timing
tWR
STOP
CONDITION
START
CONDITION
ADDRESS
ACK
8TH BIT
BYTE n
SCL
SDA
10
CAT1026, CAT1027
Doc. No. 3010, Rev. H
ACKNOWLEDGE
After a successful data transfer, each receiving device
is required to generate an acknowledge. The
acknowledging device pulls down the SDA line during
the ninth clock cycle, signaling that it received the 8 bits
of data.
The CAT1026 and CAT1027 respond with an
acknowledge after receiving a START condition and its
slave address. If the device has been selected along
with a write operation, it responds with an acknowledge
after receiving each 8-bit byte.
When the CAT1026 and CAT1027 begin a READ mode
it transmits 8 bits of data, releases the SDA line and
monitors the line for an acknowledge. Once it receives
this acknowledge, the CAT1026 and CAT1027 will
continue to transmit data. If no acknowledge is sent by
the Master, the device terminates data transmission and
waits for a STOP condition.
WRITE OPERATIONS
Byte Write
In the Byte Write mode, the Master device sends the
START condition and the slave address information (with
the R/
W
bit set to zero) to the Slave device. After the Slave
generates an acknowledge, the Master sends a 8-bit
address that is to be written into the address pointers of
the device. After receiving another acknowledge from the
Slave, the Master device transmits the data to be written
into the addressed memory location. The CAT1026 and
CAT1027 acknowledge once more and the Master
generates the STOP condition. At this time, the device
begins an internal programming cycle to non-volatile
memory. While the cycle is in progress, the device will not
respond to any request from the Master device.
Figure 8. Slave Address Bits
CAT
Default Configuration
1
0
1
0
0
0
0
R/W
START BIT
SDA
STOP BIT
SCL
Figure 6. Start/Stop Timing
ACKNOWLEDGE
1
START
SCL FROM
MASTER
8
9
DATA OUTPUT
FROM TRANSMITTER
DATA OUTPUT
FROM RECEIVER
Figure 7. Acknowledge Timing
11
CAT1026, CAT1027
Doc No. 3010, Rev. H
Page Write
The CAT1026 and CAT1027 write up to 16 bytes of data
in a single write cycle, by using the Page Write operation.
The page write operation is initiated in the same manner
as the byte write operation, however instead of terminating
after the initial byte is transmitted, the Master is allowed
to send up to 15 additional bytes. After each byte has
been transmitted, the CAT1026 and CAT1027 will respond
with an acknowledge and internally increment the lower
order address bits by one. The high order bits remain
unchanged.
If the Master transmits more than 16 bytes before sending
the STOP condition, the address counter `wraps around,'
and previously transmitted data will be overwritten.
When all 16 bytes are received, and the STOP condition
has been sent by the Master, the internal programming
cycle begins. At this point, all received data is written to
the CAT1026 and CAT1027 in a single write cycle.
BYTE
ADDRESS
SLAVE
ADDRESS
S
A
C
K
A
C
K
DATA
A
C
K
S
T
O
P
P
BUS ACTIVITY:
MASTER
SDA LINE
S
T
A
R
T
Figure 9. Byte Write Timing
BUS ACTIVITY:
MASTER
SDA LINE
DATA n+15
BYTE
ADDRESS (n)
A
C
K
A
C
K
DATA n
A
C
K
S
T
O
P
S
A
C
K
DATA n+1
A
C
K
S
T
A
R
T
P
SLAVE
ADDRESS
Figure 10. Page Write Timing
12
CAT1026, CAT1027
Doc. No. 3010, Rev. H
Acknowledge Polling
Disabling of the inputs can be used to take advantage of
the typical write cycle time. Once the stop condition is
issued to indicate the end of the host's write opration, the
CAT1026 and CAT1027 initiate the internal write cycle.
ACK polling can be initiated immediately. This involves
issuing the start condition followed by the slave address
for a write operation. If the device is still busy with the
write operation, no ACK will be returned. If a write
operation has completed, an ACK will be returned and
the host can then proceed with the next read or write
operation.
Read Operations
The READ operation for the CAT1026 and CAT1027 is
initiated in the same manner as the write operation with
one exception, the R/
W
bit is set to one. Three different
READ operations are possible: Immediate/Current
Address READ, Selective/Random READ and
Sequential READ.
SCL
SDA
8TH BIT
STOP
NO ACK
DATA OUT
8
9
SLAVE
ADDRESS
S
A
C
K
DATA
N
O
A
C
K
S
T
O
P
P
BUS ACTIVITY:
MASTER
SDA LINE
S
T
A
R
T
Figure 11. Immediate Address Read Timing
13
CAT1026, CAT1027
Doc No. 3010, Rev. H
Immediate/Current Address Read
The CAT1026 and CAT1027 address counter contains
the address of the last byte accessed, incremented by
one. In other words, if the last READ or WRITE access
was to address N, the READ immediately following
would access data from address N + 1. For N = E = 255,
the counter will wrap around to zero and continue to
clock out valid data. After the CAT1026 and CAT1027
receive a slave address (with the R/
W
bit set t o one), an
acknowledge is issued, and the requested 8-bit byte is
transmitted. The master device does not send an
acknowledge, but will generate a STOP condition.
Selective/Random Read
Selective/Random READ operations allow the Master
device to select at random any memory location for a
READ operation. The Master device first performs a
`dummy' write operation by sending the START condition,
slave address and byte addresses of the location it
wishes to read. After the CAT1026 and CAT1027
acknowledge, the Master device sends the START
condition and the slave address again, this time with the
R/
W
bit set to one. The CAT1026 and CAT1027 then
respond with an acknowledge and sends the 8-bit byte
requested. The master device does not send an
acknowledge but will generate a STOP condition.
Sequential Read
The Sequential READ operation can be initiated by
either the Immediate Address READ or Selective READ
operations. After the CAT1026 and CAT1027 send the
inital 8-bit byte requested, the Master responds with an
acknowledge which tells the device it requires more
data. The CAT1026 and CAT1027 will continue to output
an 8-bit byte for each acknowledge, thus sending the
STOP condition.
The data being transmitted from the CAT1026 and
CAT1027 is sent sequentially with the data from address
N followed by data from address N+1. The READ
operation address counter increments all of the CAT1026
and CAT1027 address bits so that the entire memory
array can be read during one operation.
SLAVE
ADDRESS
S
A
C
K
N
O
A
C
K
S
T
O
P
P
BUS ACTIVITY:
MASTER
SDA LINE
S
T
A
R
T
BYTE
ADDRESS (n)
S
A
C
K
DATA n
SLAVE
ADDRESS
A
C
K
S
T
A
R
T
BUS ACTIVITY:
MASTER
SDA LINE
DATA n+x
DATA n
A
C
K
A
C
K
DATA n+1
A
C
K
S
T
O
P
N
O
A
C
K
DATA n+2
A
C
K
P
SLAVE
ADDRESS
Figure 12. Selective Read Timing
Figure 13. Sequential Read Timing
14
CAT1026, CAT1027
Doc. No. 3010, Rev. H
d 0.08 c
f 0.10 c
0.10m C A B
0.15
8
5
A
5
B
8
3.00 + 0.15
2.00 + 0.15
0.10
0.15
0.20
0.25
PIN 1 ID
0.60 + 0.10 (8X)
d
0.15 c
2x
4.90 + 0.10
(5)
1
PIN 1 INDEX AREA
3.00 + 0.10
(S)
4
2x
d
c
4
0.30 + 0.05 (8X)
8x
j
1.95 REF. (2x)
1
0.65 TYP. (6x)
0.75 + 0.05
0.0-0.05
8x
0.20 REF.
C
NOTE:
1. ALL DIMENSION ARE IN mm. ANGLES IN DEGREES.
2. COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS THE TERMINALS.
COPLANARITY SHALL NOT EXCEED 0.08mm.
3. WARPAGE SHALL NOT EXCEED 0.10mm.
4. PACKAGE LENGTH / PACKAGE WIDTH ARE CONSIDERED AS SPECIAL
CHARACTERISTIC(S).
5. REFER TO JEDEC MO-229, FOOTPRINTS ARE COMPATIBLE TO 8 MSOP.
TDFN 3X4.9 PACKAGE (RD2)
PACKAGE OUTLINES
15
CAT1026, CAT1027
Doc No. 3010, Rev. H
3.00 + 0.10
(S)
8
5
1
4
3.00 + 0.10
(S)
PIN 1 INDEX AREA
C
0.75 + 0.05
0.0 - 0.05
0.30 + 0.07 (8x)
0.25 min.
0.75 + 0.05
A
B
5
8
2.30 + 0.10
C0.35
PIN 1 ID
1.50 + 0.10
1.95 REF. (2x)
0.65 TYP. (6x)
0.30 + 0.10 (8x)
1
2X
2X
0.15
0.15
C
C
NOTE:
1. ALL DIMENSION ARE IN mm. ANGLES IN DEGREES.
2. COPLANARITY SHALL NOT EXCEED 0.08 mm.
3. WARPAGE SHALL NOT EXCEED 0.10 mm.
4. PACKAGE LENGTH / PACKAGE WIDTH ARE CONSIDERED AS SPECIAL CHARACTERISTIC(S)
5. REFER JEDEC MO-229 / WEEC
TDFN 3X3 PACKAGE (RD4)
16
CAT1026, CAT1027
Doc. No. 3010, Rev. H
Ordering Information
Note:
(1) The device used in the above example is a CAT1026SI-30TE13 (Supervisory circuit with I2C serial 2k CMOS EEPROM, SOIC, Industrial
Temperature, 3.0-3.15V Reset Threshold Voltage, Tape and Reel).
1 0 2 6
Temperature Range
I = Industrial (-40C to 85C)
Prefix
Device #
Suffix
S
I
Product
Number
1026: 2K
Package
P: PDIP
S: SOIC
R: MSOP
U: TSSOP
RD2: 8-pad TDFN
(3x4.9mm, MSOP Footprint)
RD4: 8-pad TDFN (3x3mm)
L: PDIP (Lead free, Halogen free)
V: SOIC (Lead free, Halogen free)
Y: TSSOP (Lead free, Halogen free)
Z: MSOP (Lead free, Halogen free)
ZD2: TDFN 3x4.9mm (Lead free, Halogen free)
ZD4: TDFN 3x3mm (Lead free, Halogen free)
-30
CAT
Reset Threshold
Voltage
45: 4.5-4.75V
42: 4.25-4.5V
30: 3.0-3.15V
28: 2.85-3.0V
25: 2.55-2.7V
Optional
Company ID
1027: 2K
E = Extended (-40C to +125C)
TE13
Tape & Reel
SOIC: 2000/Reel
TSSOP: 2000/Reel
MSOP: 2500/Reel
Catalyst Semiconductor, Inc.
Corporate Headquarters
1250 Borregas Avenue
Sunnyvale, CA 94089
Phone: 408.542.1000
Fax: 408.542.1200
www.catalyst-semiconductor.com
Copyrights, Trademarks and Patents
Trademarks and registered trademarks of Catalyst Semiconductor include each of the following:
DPP TM
AE
2
TM
I
2
C is a trademark of Philips Corporation.
Catalyst Semiconductor has been issued U.S. and foreign patents and has patent applications pending that protect its products. For a complete list of patents
issued to Catalyst Semiconductor contact the Company's corporate office at 408.542.1000.
CATALYST SEMICONDUCTOR MAKES NO WARRANTY, REPRESENTATION OR GUARANTEE, EXPRESS OR IMPLIED, REGARDING THE SUITABILITY OF ITS
PRODUCTS FOR ANY PARTICULAR PURPOSE, NOR THAT THE USE OF ITS PRODUCTS WILL NOT INFRINGE ITS INTELLECTUAL PROPERTY RIGHTS OR THE
RIGHTS OF THIRD PARTIES WITH RESPECT TO ANY PARTICULAR USE OR APPLICATION AND SPECIFICALLY DISCLAIMS ANY AND ALL LIABILITY ARISING
OUT OF ANY SUCH USE OR APPLICATION, INCLUDING BUT NOT LIMITED TO, CONSEQUENTIAL OR INCIDENTAL DAMAGES.
Catalyst Semiconductor products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or
other applications intended to support or sustain life, or for any other application in which the failure of the Catalyst Semiconductor product could create a
situation where personal injury or death may occur.
Catalyst Semiconductor reserves the right to make changes to or discontinue any product or service described herein without notice. Products with data sheets
labeled "Advance Information" or "Preliminary" and other products described herein may not be in production or offered for sale.
Catalyst Semiconductor advises customers to obtain the current version of the relevant product information before placing orders. Circuit diagrams illustrate
typical semiconductor applications and may not be complete.
Publication #:
3010
Revison:
H
Issue date:
4/12/04
REVISION HISTORY
Date
Rev.
Reason
9/25/2003
F
Added Green Package logo
Updated DC Operating Characteristic notes
Updated Reliability Characteristics notes
11/7/2003
G
Eliminated Automotive temperature range
Updated Ordering Information with "Green" package
marking codes
4/12/2004
H
Eliminated data sheet designation
Updated Reel Ordering Information
PDF 
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