mx25l12845e Macronix International Co., mx25l12845e Datasheet - Page 23

• Manufacturer Part Number: mx25l12845e
• Description: Mx25l12845e High Performance Serial Flash Specification Preliminary
• Manufacturer: Macronix International Co.

MX25L12845E
(16) Chip Erase (CE)
The Chip Erase (CE) instruction is for erasing the data of the whole chip to be "1". A Write Enable (WREN) instruc-
tion must execute to set the Write Enable Latch (WEL) bit before sending the Chip Erase (CE). The CS# must go
high exactly at the byte boundary; otherwise, the instruction will be rejected and not executed.
The sequence of issuing CE instruction is: CS# goes low → sending CE instruction code → CS# goes high. (see
Figure 31)
The self-timed Chip Erase Cycle time (tCE) is initiated as soon as Chip Select (CS#) goes high. The Write in
Progress (WIP) bit still can be check out during the Chip Erase cycle is in progress. The WIP sets 1 during the tCE
timing, and sets 0 when Chip Erase Cycle is completed, and the Write Enable Latch (WEL) bit is reset. If the chip is
protected the Chip Erase (CE) instruction will not be executed, but WEL will be reset.
(17) Page Program (PP)
The Page Program (PP) instruction is for programming the memory to be "0". A Write Enable (WREN) instruction
must execute to set the Write Enable Latch (WEL) bit before sending the Page Program (PP). The device pro-
grams only the last 256 data bytes sent to the device. If the entire 256 data bytes are going to be programmed, A7-
A0 (The eight least significant address bits) should be set to 0. If the eight least significant address bits (A7-A0) are
not all 0, all transmitted data going beyond the end of the current page are programmed from the start address of
the same page (from the address A7-A0 are all 0).
If more than 256 bytes are sent to the device, the data of the
last 256-byte is programmed at the request page and previous data will be disregarded. If less than 256 bytes are
sent to the device, the data is programmed at the requested address of the page without effect on other address of
the same page.
The sequence of issuing PP instruction is: CS# goes low→ sending PP instruction code→ 3-byte address on SI→
at least 1-byte on data on SI→ CS# goes high. (see Figure 26)
The CS# must be kept to low during the whole Page Program cycle; The CS# must go high exactly at the byte
boundary( the latest eighth bit of data being latched in), otherwise, the instruction will be rejected and will not be ex-
ecuted.
The self-timed Page Program Cycle time (tPP) is initiated as soon as Chip Select (CS#) goes high. The Write in
Progress (WIP) bit still can be check out during the Page Program cycle is in progress. The WIP sets 1 during the
tPP timing, and sets 0 when Page Program Cycle is completed, and the Write Enable Latch (WEL) bit is reset. If
the page is protected by BP3~0 (WPSEL=0) or by individual lock (WPSEL=1), the array data will be protected (no
change) and the WEL bit will still be reset.
(18) 4 x I/O Page Program (4PP)
The Quad Page Program (4PP) instruction is for programming the memory to be "0". A Write Enable (WREN) in-
struction must execute to set the Write Enable Latch (WEL) bit and Quad Enable (QE) bit must be set to "1" before
sending the Quad Page Program (4PP). The Quad Page Programming takes four pins: SIO0, SIO1, SIO2, and
SIO3, which can raise programer performance and and the effectiveness of application of lower clock less than
20MHz. For system with faster clock, the Quad page program cannot provide more actual favors, because the re-
quired internal page program time is far more than the time data flows in. Therefore, we suggest that while execut-
ing this command (especially during sending data), user can slow the clock speed down to 20MHz below. The other
function descriptions are as same as standard page program.
The sequence of issuing 4PP instruction is: CS# goes low→ sending 4PP instruction code→ 3-byte address on
SIO[3:0]→ at least 1-byte on data on SIO[3:0]→ CS# goes high. (see Figure 27)
P/N: PM1428
REV. 0.06, MAR. 05, 2009
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