Absolute Maximum Ratings*
*NOTICE:
Stresses beyond those listed under “Absolute
Maximum Ratings” may cause permanent dam-
age to the device. This is a stress rating only and
functional operation of the device at these or any
other conditions beyond those indicated in the
operational sections of this specification is not
implied. Exposure to absolute maximum rating
conditions for extended periods may affect device
reliability.
Operating Temperature ................................. -55°C to +125°C
Storage Temperature .................................... -65°C to +150°C
Voltage on Any Pin
with Respect to Ground.....................................-1.0V to +7.0V
Maximum Operating Voltage........................................... 6.25V
DC Output Current........................................................ 5.0 mA
Block Diagram
SERIAL CLOCK (VCLK): Upon power-up, the device is in
the Transmit-Only mode and will transmit the entire mem-
ory contents via the SDA pin with positive signals on the
VCLK pin.
Pin Description
SERIAL CLOCK (SCL): The SCL input is used to positive
edge clock data into each EEPROM device and negative
edge clock data out of each device.
SERIAL DATA (SDA): The SDA pin is bidirectional for
serial data transfer. This pin is open-drain driven and may
be wire-ORed with any number of other open drain or open
collector devices.
Memory Organization
AT24C21, 1K SERIAL EEPROM: Internally organized with
128 pages of one byte each. The 1K requires a 7-bit data
word address for random word addressing.
AT24C21
2
ATMEL [ ATMEL ]
