le25lb643 Sanyo Semiconductor Corporation, le25lb643 Datasheet - Page 11

• Manufacturer Part Number: le25lb643
• Description: Serial Eeprom
• Manufacturer: Sanyo Semiconductor Corporation

5. Write (WRITE)
Figure 9 Write
6. Hold Function
Figure 10 HOLD
CS
SCK
SI
SO
The LE25LB643 enables pages with up to 32bytes to be written. Any number of bytes from 1 to 32bytes can be written
within the same sector page (page addresses : A15 to A5). “Figure 9 Write” shows the write timing waveforms, and
Figure 12 shows a write flowchart. After the falling CS edge, the command (02H) is input followed by the 16-bit
addresses (Add). The write data is then loaded until the rising CS edge, and the internal addresses (A4 to A0) are
incremented (Add+1) every time the data is loaded in 1-byte increments. The data loading continues until the rising CS
edge. If the data loaded has exceeded 32bytes, the 32bytes loaded last are written. The write data must be loaded in
1-byte increments, and the write operation is not performed at the rising CS edge occurring at any other timing. The
write time is 10ms (max.) when 32bytes (1page) are written at one time.
• Addresses A15 - A13 are “don’t care .”
Using HOLD pin, the hold function suspends serial communication (it places it in the hold status). “Figure 10 HOLD”
shows the timing waveforms. The device is placed in the hold status at the falling HOLD edge while the logic level of
SCK is low, and it exits from the hold status at the rising HOLD edge. When the logic level of SCK is high, HOLD must
not rise or fall. The hold function takes effect when the logic of CS is low, and the hold status is exited and serial
communication is reset at the rising CS edge. In the hold status, the SO output is in the high-impedance state, and SI
and SCK are “don’t care.”
Mode3
Mode0
CS
SCK
HOLD
SO
0
1
2
(00000010)
8CLK
3 4
02h
5
6
Active
7
(A15-A8)
t HH
8
Add.
High Impedance
t HS
t HHZ
15 16
LE25LB643
(A7-A0)
Add.
23 24
High Impedance
HOLD
PD
(N)
31 32
(N+1)
PD
t HH
39 40
t HS
t HLZ
(N+2)
PD
47
Active
(N+31)
PD
279
Write Cycle
No.NA1342-11/14
Self-timed
t WC