AT24C256B-PU Atmel, AT24C256B-PU Datasheet - Page 3

• Manufacturer Part Number: AT24C256B-PU
• Description: IC EEPROM 256KBIT 1MHZ 8DIP
• Manufacturer: Atmel

Specifications of AT24C256B-PU

• Format - Memory: EEPROMs - Serial
• Memory Type: EEPROM
• Memory Size: 256K (32K 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-DIP (0.300", 7.62mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

2. Pin Description
3. Memory Organization
Table 3-1.
Applicable over recommended operating range from T
Note:
5279C–SEEPR–3/09
Symbol
C
C
I/O
IN
1. This parameter is characterized and is not 100% tested.
Test Condition
Input/Output Capacitance (SDA)
Input Capacitance (A
Pin Capacitance
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.
DEVICE/PAGE ADDRESSES (A2, A1, A0): The A2, A1, and A0 pins are device address inputs
that are hardwired (directly to GND or to Vcc) for compatibility with other AT24Cxx devices.
When the pins are hardwired, as many as eight 256K devices may be addressed on a single bus
system. (Device addressing is discussed in detail under “Device Addressing,”
is selected when a corresponding hardware and software match is true. If these pins are left
floating, the A2, A1, and A0 pins will be internally pulled down to GND. However, due to capaci-
tive coupling that may appear during customer applications, Atmel recommends always
connecting the address pins to a known state. When using a pull-up resistor, Atmel recommends
using 10k or less.
WRITE PROTECT (WP): The write protect input, when connected to GND, allows normal write
operations. When WP is connected directly to Vcc, all write operations to the memory are inhib-
ited. If the pin is left floating, the WP pin will be internally pulled down to GND. However, due to
capacitive coupling that may appear during customer applications, Atmel recommends always
connecting the WP pins to a known state. When using a pull-up resistor, Atmel recommends
using 10k or less.
AT24C256B, 256K SERIAL EEPROM: The 256K is internally organized as 512 pages of 64
bytes each. Random word addressing requires a 15-bit data word address.
(1)
0
, A
1
, SCL)
A
= 25C, f = 1.0 MHz, V
CC
Max
8
6
= +1.8V
Units
pF
pF
AT24C256B
page
Conditions
V
9.) A device
V
I/O
IN
= 0V
= 0V
3