NM24C32U Datasheet, PDF (1/12 Pages) Fairchild Semiconductor – 32K-Bit Serial EEPROM with Write Protect 2-Wire Bus Interface

PRELIMINARY
August 1999
NM24C32U
32K-Bit Serial EEPROM with Write Protect
2-Wire Bus Interface
General Description:
The NM24C32U is a 32K (32,768) bit serial interface CMOS
EEPROM (Electrically Erasable Programmable Read-Only
Memory). This device fully conforms to the Extended I²C™ 2-wire
protocol which uses Clock (SCL) and Data I/O (SDA) pins to
synchronously clock data between the "master" (for example a
microprocessor) and the "slave" (the EEPROM device). In addi-
tion, the serial interface allows a minimal pin count packaging
designed to simplify PC board layout requirements and offers the
designer a variety of low voltage and low power options.
NM24C32U incorporates a hardware "Write Protect" feature, by
which, the upper half of the memory can be disabled against
programming by connecting the WP pin to V_CC. This section of
memory then effectively becomes a ROM (Read-Only Memory)
and can no longer be programmed as long as WP pin is connected
to V_CC.
Fairchild EEPROMs are designed and tested for applications requir-
ing high endurance, high reliability and low power consumption for a
continuously reliable non-volatile solution for all markets.
Block Diagram
Functions
I I²C™ compatible interface
I 32,768 bits organized as 4,096 x 8
I Extended 2.7V – 5.5V operating voltage
I 100 KHz or 400 KHz operation
I Self timed programming cycle (6ms typical)
I "Programming complete" indicated by ACK polling
I Memory "Upper Block" Write Protect pin
Features
I The I²C™ interface allows the smallest I/O pincount of any
EEPROM interface
I 32 byte page write mode to minimize total write time per byte
I Low V_CC programming lockout (3.8V)
— "H" option (Standard V_CC range) parts only
I Typical 200µA active current (I_CCA)
I Typical 1µA standby current (I_SB) for "L" devices and 0.1µA
standby current for "LZ" devices
I Endurance: Up to 1,000,000 data changes
I Data retention greater than 40 years
VCC
WP
SDA
SCL
A2
A1
A0
WRITE
LOCKOUT
START
STOP
LOGIC
START CYCLE
SLAVE ADDRESS
REGISTER &
COMPARATOR
CONTROL
LOGIC
LOAD
INC
WORD
ADDRESS
COUNTER
XDEC
H.V. GENERATION
TIMING &CONTROL
E2PROM
ARRAY
R/W
YDEC
CK
DIN
DATA REGISTER
DOUT
I²C™ is a registered trademark of Philips Electronics N.V.
© 1999 Fairchild Semiconductor Corporation
1
NM24C32U Rev. C.1
DS800011-1
www.fairchildsemi.com