M34D64-R STMICROELECTRONICS [STMicroelectronics], M34D64-R Datasheet - Page 2

• Manufacturer Part Number: M34D64-R
• Description: 64 Kbit Serial I2C Bus EEPROM With Hardware Write Control on Top Quarter of Memory
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

M34D64
SUMMARY DESCRIPTION
These
programmable memory (EEPROM) devices are
organized as 8192 x 8.
Figure 2. Logic Diagram
These devices are compatible with the I
memory protocol. This is a two wire serial interface
that uses a bi-directional data bus and serial clock.
The devices carry a built-in 4-bit Device Type
Identifier code (1010) in accordance with the I
bus definition.
The device behaves as a slave in the I
with all memory operations synchronized by the
serial clock. Read and Write operations are
initiated by a Start condition, generated by the bus
master. The Start condition is followed by a Device
Select Code and RW bit (as described in Table 2),
terminated by an acknowledge bit.
When writing data to the memory, the device
inserts an acknowledge bit during the 9
following the bus master’s 8-bit transmission.
When data is read by the bus master, the bus
master acknowledges the receipt of the data byte
in the same way. Data transfers are terminated by
a Stop condition after an Ack for Write, and after a
NoAck for Read.
2/21
E0-E2
SCL
WC
I
2
C-compatible
3
V CC
V SS
M34D64
electrically
2
C protocol,
SDA
th
AI02850B
erasable
bit time,
2
2
C
C
Table 1. Signal Names
Power On Reset: V
In order to prevent data corruption and inadvertent
Write operations during Power-up, a Power On
Reset (POR) circuit is included. The internal reset
is held active until V
threshold value, and all operations are disabled –
the device will not respond to any command. In the
same way, when V
voltage, below the POR threshold value, all
operations are disabled and the device will not
respond to any command. A stable and valid V
must be applied before applying any logic signal.
Figure 3. SO and TSSOP Connections
Note: 1. See page 17 (onwards) for package dimensions, and how
E0, E1, E2
SDA
SCL
WC
V
V
CC
SS
to identify pin-1.
V SS
E0
E1
E2
CC
CC
1
2
3
4
Chip Enable
Serial Data
Serial Clock
Write Control
Supply Voltage
Ground
M34D64
CC
Lock-Out Write Protect
drops from the operating
AI02851C
has reached the POR
8
7
6
5
V CC
WC
SCL
SDA
CC