AT24C256C-XHL-B Atmel, AT24C256C-XHL-B Datasheet - Page 9

• Manufacturer Part Number: AT24C256C-XHL-B
• Description: IC EEPROM 256KBIT IND 8TSSOP
• Manufacturer: Atmel

Specifications of AT24C256C-XHL-B

• Format - Memory: EEPROMs - Serial
• Memory Type: EEPROM
• Memory Size: 256K (32K x 8)
• Speed: 400kHz, 1MHz
• Interface: I²C, 2-Wire Serial
• Voltage - Supply: 1.7 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-TSSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

5.
8568C–SEEPR–5/10
Device Addressing
The 256K EEPROM requires an 8-bit device address word following a start condition to enable the chip for a read
or write operation (refer to Figure 8). The device address word consists of a mandatory “1”, “0” sequence for the
first four most significant bits as shown. This is common to all two-wire EEPROM devices.
Figure 5-1.
The next three bits are the A2, A1, A0 device address bits to allow as many as eight devices on the same bus.
These bits must compare to their corresponding hardwired input pins. The A2, A1, and A0 pins use an internal
proprietary circuit that biases them to a logic low condition if the pins are allowed to float.
The eighth bit of the device address is the read/write operation select bit. A read operation is initiated if this bit is
high, and a write operation is initiated if this bit is low.
Upon a compare of the device address, the EEPROM will output a “0”. If a compare is not made, the device will
return to a standby state.
DATA SECURITY: The Atmel
protect the whole memory when the WP pin is at V
MSB
1
0
Device Addressing
1
0
®
AT24C256C has a hardware data protection scheme that allows the user to write
A2
A1
CC
A0
.
R/W
LSB
Atmel AT24C256C
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