S-93L76A Datasheet, PDF (12/34 Pages) Seiko Instruments Inc – LOW VOLTAGE OPERATION CMOS SERIAL E2PROM

LOW VOLTAGE OPERATION CMOS SERIAL E²PROM
S-93L76A
Rev.2.2_00
„ Write Disable Function when Power Supply Voltage is Low
The S-93L76A provides a built-in detector to detect a low power supply voltage and disable writing. When
the power supply voltage is low or at power application, the write instructions (WRITE, ERASE, WRAL, and
ERAL) are cancelled, and the write disable state (EWDS) is automatically set. The detection voltage and
the release voltage are 1.4 V typ. (refer to Figure 12).
Therefore, when a write operation is performed after the power supply voltage has dropped and then risen
again up to the level at which writing is possible, a write enable instruction (EWEN) must be sent before a
write instruction (WRITE, ERASE, WRAL, or ERAL) is executed.
When the power supply voltage drops during a write operation, the data being written to an address at that
time is not guaranteed.
Power supply voltage
Detection voltage (−V_DET)
1.4 V Typ.
Release voltage (+V_DET)
1.4 V Typ.
Write instruction cancelled
Write disable state (EWDS) automatically set
Figure 12 Operation when Power Supply Voltage is Low
12
Seiko Instruments Inc.