S-93C46BD0I-I8T1G SII [Seiko Instruments Inc], S-93C46BD0I-I8T1G Datasheet - Page 19

• Manufacturer Part Number: S-93C46BD0I-I8T1G
• Description: 3-WIRE SERIAL E2PROM
• Manufacturer: SII [Seiko Instruments Inc]

Rev.7.0
Write Protect Function during the Low Power Supply Voltage
The S-93C46B/56B/66B provides a built-in detector. 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 is 1.75 V typ., the release voltage is 2.05 V typ., and there is a hysteresis of
about 0.3 V (refer to Figure 21 ). 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.
_00
Power supply voltage
Detection voltage (−V
1.75 V Typ.
Figure 21 Operation during Low Power Supply Voltage
DET
)
Seiko Instruments Inc.
Write instruction cancelled
Write disable state (EWDS) automatically set
Hysteresis
About 0.3 V
3-WIRE SERIAL E
Release voltage (+V
2.05 V Typ.
S-93C46B/56B/66B
DET
)
2
PROM
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