M95512-W STMICROELECTRONICS [STMicroelectronics], M95512-W Datasheet - Page 13

• Manufacturer Part Number: M95512-W
• Description: 512Kbit Serial SPI Bus EEPROM With High Speed Clock
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

Write Enable (WREN)
The Write Enable Latch (WEL) bit must be set pri-
or to each WRITE and WRSR instruction. The only
way to do this is to send a Write Enable instruction
to the device.
Figure 8. Write Enable (WREN) Sequence
Write Disable (WRDI)
One way of resetting the Write Enable Latch
(WEL) bit is to send a Write Disable instruction to
the device.
As shown in
the device, Chip Select (S) is driven Low, and the
bits of the instruction byte are shifted in, on Serial
Data Input (D).
Figure 9. Write Disable (WRDI) Sequence
Figure
9., to send this instruction to
S
C
D
Q
S
C
D
Q
High Impedance
High Impedance
0
0
1
1
2
2
Instruction
Instruction
3
3
4
4
As shown in
the device, Chip Select (S) is driven Low, and the
bits of the instruction byte are shifted in, on Serial
Data Input (D). The device then enters a wait
state. It waits for a the device to be deselected, by
Chip Select (S) being driven High.
The device then enters a wait state. It waits for a
the device to be deselected, by Chip Select (S) be-
ing driven High.
The Write Enable Latch (WEL) bit, in fact, be-
comes reset by any of the following events:
–
–
–
–
5
5
Power-up
WRDI instruction execution
WRSR instruction completion
WRITE instruction completion.
6
6
7
7
Figure
AI02281E
AI03750D
8., to send this instruction to
M95512-W, M95512-R
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