20 Megabit (512K x 40-Bit) EEPROM MCM
Data Polling
79LV2040
Data Polling function allows the status of the EEPROM to be determined. If EEPROM is set to read mode during a
write cycle, an inversion of the last byte of data to be loaded outputs from I/O 7 to indicate that the EEPROM is per-
forming a write operation.
RDY/Busy Signal
RDY/Busy signal also allows a comparison operation to determine the status of the EEPROM. The RDY/Busy signal
goes low (V
OL)
after the first write signal. At the end of the write cycle, the RDY/Busy returns to a high state ( V
OH
).
RES Signal
When RES is LOW (V
L
), the EEPROM cannot be read or programmed. The EEPROM data must be protected by
keeping RES low when V
CC
is power on and off. RES should be high (V
H
) during read and programming operations.
Memory
Data Protection
To protect the data during operation and power on/off, the EEPROM has the internal functions described below.
1. Data Protection against Noise of Control Pins (CE, OE, WE) during Operation.
During readout or standby, noise on the control pins may act as a trigger and turn the EEPROM to programming
mode by mistake. To prevent this phenomenon, the EEPROM has a noise cancellation function that cuts noise if its
width is 20ns or less in programming mode. Be careful not to allow noise of a width more than 20ns on the control
pins
.
09.07.05 Rev 1
All data sheets are subject to change without notice
12
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