ACE24C02 Datasheet, PDF (7/20 Pages) ACE Technology Co., LTD. – Two-wire Serial EEPROM

ACE24C02/04/08/16B
Two-wire Serial EEPROM
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 to Figure 1). 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 to Figure 2).
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 to Figure 2).
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. The happens during the ninth
clock cycle.
Standby Mode :
The ACE24C02/04/08/16B 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.
Memory Reset :
After an interruption in protocol power loss or system reset, any two-wire part can be protocol reset by following
these steps:
1. Clock up to 9 cycles.
2. Look for SDA high in each cycle while SCL is high and then.
3. Create a start condition.
Bus Timing
Figure 1．Data Validity
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