CAT1025WI-28-GT3 ON Semiconductor, CAT1025WI-28-GT3 Datasheet - Page 9

• Manufacturer Part Number: CAT1025WI-28-GT3
• Description: IC SUPERVISR CPU 2K EEPROM 8SOIC
• Manufacturer: ON Semiconductor
• Type: Simple Reset/Power-On Resetr

Specifications of CAT1025WI-28-GT3

• Number Of Voltages Monitored: 1
• Output: Open Drain or Open Collector
• Reset: Active High/Active Low
• Reset Timeout: 130 ms Minimum
• Voltage - Threshold: 2.85V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

EMBEDDED EEPROM OPERATION
The CAT1024 and CAT1025 feature a 2-kbit embedded
serial EEPROM that supports the I
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
The features of the I
follows:
(1) Data transfer may be initiated only when the bus
(2) During a data transfer, the data line must remain
START CONDITION
The START Condition precedes all commands to the
device, and is defined as a HIGH to LOW transition of
Figure 3. Bus Timing
Figure 4. Write Cycle Timing
© 2009 SCILLC. All rights reserved.
Characteristics subject to change without notice
2
C BUS PROTOCOL
is not busy.
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.
SCL
SDA
SDA OUT
SDA IN
SCL
2
t SU:STA
C bus protocol are defined as
8TH BIT
BYTE n
t F
t HD:STA
t LOW
2
C Bus data
t AA
ACK
t HD:DAT
t HIGH
t LOW
STOP
CONDITION
9
t DH
SDA when SCL is HIGH. The CAT1024/25 monitors
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 CAT1024/25 monitors the bus
and responds with an acknowledge (on the SDA line)
when its address matches the transmitted slave
address. The CAT1024/25 then perform a Read or
Write operation depending on the R/W ¯ ¯ bit.
t SU:DAT
t R
t WR
START
CONDITION
t SU:STO
t BUF
CAT1024, CAT1025
ADDRESS
Doc. No. MD-3008 Rev. R