EN25D16
Chip Erase (CE) (C7h/60h)
The Chip Erase (CE) instruction sets all bits to 1 (FFh). Before it can be accepted, a Write Enable
(WREN) instruction must previously have been executed. After the Write Enable (WREN) instruction
has been decoded, the device sets the Write Enable Latch (WEL).
The Chip Erase (CE) instruction is entered by driving Chip Select (CS#) Low, followed by the
instruction code on Serial Data Input (DI). Chip Select (CS#) must be driven Low for the entire
duration of the sequence.
The instruction sequence is shown in Figure 15. Chip Select (CS#) must be driven High after the
eighth bit of the instruction code has been latched in, otherwise the Chip Erase instruction is not
executed. As soon as Chip Select (CS#) is driven High, the self-timed Chip Erase cycle (whose
duration is t ) is initiated. While the Chip Erase cycle is in progress, the Status Register may be
CE
read to check the value of the Write In Progress (WIP) bit. The Write In Progress (WIP) bit is 1
during the self-timed Chip Erase cycle, and is 0 when it is completed. At some unspecified time
before the cycle is completed, the Write Enable Latch (WEL) bit is reset.
The Chip Erase (CE) instruction is executed only if all Block Protect (BP2, BP1, BP0) bits are 0. The
Chip Erase (CE) instruction is ignored if one, or more, sectors are protected.
Figure 15. Chip Erase Instruction Sequence Diagram
Deep Power-down (DP) (B9h)
Executing the Deep Power-down (DP) instruction is the only way to put the device in the lowest con-
sumption mode (the Deep Power-down mode). It can also be used as an extra software protection
mechanism, while the device is not in active use, since in this mode, the device ignores all Write,
Program and Erase instructions.
Driving Chip Select (CS#) High deselects the device, and puts the device in the Standby mode (if
there is no internal cycle currently in progress). But this mode is not the Deep Power-down mode.
The Deep Power-down mode can only be entered by executing the Deep Power-down (DP)
instruction, to reduce the standby current (from ICC1 to ICC2, as specified in Table 8.).
Once the device has entered the Deep Power-down mode, all instructions are ignored except the
Release from Deep Power-down and Read Device ID (RDI) instruction. This releases the device
from this mode. The Release from Deep Power-down and Read Device ID (RDI) instruction also
allows the Device ID of the device to be output on Serial Data Output (DO).
The Deep Power-down mode automatically stops at Power-down, and the device always Powers-up
in the Standby mode. The Deep Power-down (DP) instruction is entered by driving Chip Select (CS#)
Low, followed by the instruction code on Serial Data Input (DI). Chip Select (CS#) must be driven
Low for the entire duration of the sequence.
The instruction sequence is shown in Figure 16..Chip Select (CS#) must be driven High after the
eighth bit of the instruction code has been latched in, otherwise the Deep Power-down (DP)
instruction is not executed. As soon as Chip Select (CS#) is driven High, it requires a delay of t
DP
before the supply current is reduced to ICC2 and the Deep Power-down mode is entered.
Any Deep Power-down (DP) instruction, while an Erase, Program or Write cycle is in progress, is
rejected without having any effects on the cycle that is in progress.
This Data Sheet may be revised by subsequent versions
or modifications due to changes in technical specifications.
©2004 Eon Silicon Solution, Inc., www.essi.com.tw
20
Rev. B, Issue Date: 2008/06/23