IS24C32A-2ZLI-TR ISSI, Integrated Silicon Solution Inc, IS24C32A-2ZLI-TR Datasheet - Page 5

• Manufacturer Part Number: IS24C32A-2ZLI-TR
• Description: IC EEPROM 32KBIT 1MHZ 8TSSOP
• Manufacturer: ISSI, Integrated Silicon Solution Inc

Specifications of IS24C32A-2ZLI-TR

• Format - Memory: EEPROMs - Serial
• Memory Type: EEPROM
• Memory Size: 32K (4K x 8)
• Speed: 400kHz, 1MHz
• Interface: I²C, 2-Wire Serial
• Voltage - Supply: 1.8 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-TSSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

IS24C32A/B
IS24C64A/B
DEVICE ADDRESSING
The Master begins a transmission by sending a Start
condition. The Master then sends the address of the
particular Slave devices it is requesting. The Slave
device (Fig. 5) address is 8 bits.
The four most significant bits of the Slave address are fixed
as 1010 for the IS24CXX.
The next three bits of the Slave address are A0, A1, and
A2, and are used in comparison with the hard-wired input
values on the A0, A1, and A2 pins. Up to eight IS24CXX
units may share the 2-wire bus.
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 transmits the Start condition and Slave
address byte (Fig. 5), the appropriate 2-wire Slave
(eg.IS24C64A) will respond with ACK on the SDA line. The
Slave will pull down the SDA on the ninth clock cycle,
signaling that it received the eight bits of data. The selected
EEPROM then prepares for a Read or Write operation by
monitoring the bus.
Integrated Silicon Solution, Inc. | www.issi.com
Rev. D
01/04/08
WRITE OPERATION
Byte Write
In the Byte Write mode, the Master device sends the Start
condition and the Slave address information (with the R/W
set to Zero) to the Slave device. After the Slave generates
an ACK, the Master sends the two byte address that is to
be written into the address pointer of the IS24CXX. After
receiving another ACK from the Slave, the Master device
transmits the data byte to be written into the address
memory location. The IS24CXX acknowledges once more
and the Master generates the Stop condition, at which time
the device begins its internal programming cycle. While
this internal cycle is in progress, the device will not respond
to any request from the Master device.
Page Write
The IS24CXX is capable of 32-byte Page-Write operation. A
Page-Write is initiated in the same manner as a Byte Write,
but instead of terminating the internal Write cycle after the
first data word is transferred, the Master device can transmit
up to 31 more bytes. After the receipt of each data word, the
EEPROM responds immediately with an ACK on SDA line,
and the five lower order data word address bits are internally
incremented by one, while the higher order bits of the data
word address remain constant. If a byte address is
incremented from the last byte of a page, it returns to the
first byte of that page. If the Master device should transmit
more than 32 bytes prior to issuing the Stop condition, the
address counter will “roll over,” and the previously written data
will be overwritten. Once all 32 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 IS24CXX in a single Write cycle. All inputs are
disabled until completion of the internal Write cycle.
Acknowledge (ACK) Polling
The 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 operation, the
IS24CXX initiates 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 EEPROM is still busy with the Write operation, no ACK
will be returned. If the IS24CXX has completed the Write
operation, an ACK will be returned and the host can then
proceed with the next Read or Write operation.
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