LE25U40CMC

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12

7. Small Sector Erase

Small sector erase is an operation that sets the memory cell data in any small sector to "1". A small sector consists of

4Kbytes. "Figure 12 Small Sector Erase" shows the timing waveforms, and Figure 21 shows a small sector erase

flowchart. The small sector erase command consists of the first through fourth bus cycles, and it is initiated by inputting

the 24-bit addresses following (20h) or (D7h). Addresses A18 to A12 are valid, and Addresses A23 to A19 are "don't

care". After the command has been input, the internal erase operation starts from the rising CS edge, and it ends

automatically by the control exercised by the internal timer. Erase end can also be detected using status register RDY.

Figure 12 Small Sector Erase

8. Sector Erase

Sector erase is an operation that sets the memory cell data in any sector to "1". A sector consists of 64Kbytes. "Figure

13 Sector Erase" shows the timing waveforms, and Figure 21 shows a sector erase flowchart. The sector erase command

consists of the first through fourth bus cycles, and it is initiated by inputting the 24-bit addresses following (D8h).

Addresses A18 to A16 are valid, and Addresses A23 to A19 are "don't care". After the command has been input, the

internal erase operation starts from the rising CS edge, and it ends automatically by the control exercised by the internal

timer. Erase end can also be detected using status register RDY.

Figure 13 Sector Erase

Self-timed

Erase Cycle

SCK

SI

High Impedance

SO

CS

tSSE

Add.

20h / D7h

Add.

Add.

15

0

1

2

3

4

5

6

7

8

23

16

24

31

Mode3

Mode0

8CLK

MSB

SCK

SI

High Impedance

SO

CS

tSE

Self-timed

Erase Cycle

Add.

D8h

Add.

Add.

15

0

1

2

3

4

5

6

7

8

23

16

24

31

Mode3

Mode0

8CLK

MSB