AT24C16B_08 Datasheet, PDF (6/27 Pages) ATMEL Corporation – Two-wire Serial EEPROM

5. Device Operation
CLOCK and DATA TRANSITIONS: The SDA pin is normally pulled high with an external device.
Data on the SDA pin may change only during SCL low time periods (see Figure 7-2 on page 8).
Data changes during SCL high periods will indicate a start or stop condition as defined below.
START CONDITION: A high-to-low transition of SDA with SCL high is a start condition which
must precede any other command (see Figure 7-3 on page 8).
STOP CONDITION: A low-to-high transition of SDA with SCL high is a stop condition. After a
read sequence, the stop command will place the EEPROM in a standby power mode (see Fig-
ure 7-3 on page 8).
ACKNOWLEDGE: All addresses and data words are serially transmitted to and from the
EEPROM in 8-bit words. The EEPROM sends a zero to acknowledge that it has received each
word. This happens during the ninth clock cycle.
STANDBY MODE: The AT24C16B features a low-power standby mode which is enabled: (a)
upon power-up and (b) after the receipt of the STOP bit and the completion of any internal
operations.
2-WIRE SOFTWARE RESET: After an interruption in protocol, power loss or system reset, any
2-wire part can be protocol reset by following these steps:
1. Create a start bit condition.
2. Clock 9 cycles.
3. Create another start bit followed by stop bit condition as shown below.
Start bit
SCL
1
Dummy Clock Cycles
2
3
8
Start bit
9
Stop bit
SDA
6 AT24C16B
5175D–SEEPR–6/08