S93L76A Datasheet, PDF (14/37 Pages) Seiko Instruments Inc – LOW VOLTAGE OPERATION 3-WIRE SERIAL E2PROM

LOW VOLTAGE OPERATION 3-WIRE SERIAL E²PROM
S-93L76A
Rev.6.0_02
 Write Protect Function during the Low Power Supply Voltage
The S-93L76A provides a built-in detection circuit to detect a low power supply voltage. When the power supply
voltage is low or at power-on, 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 during Low Power Supply Voltage
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