EN25Q16 Datasheet, PDF (8/40 Pages) Eon Silicon Solution Inc. – 16 Megabit Serial Flash Memory with 4Kbyte Uniform Sector

EN25Q16
throughout the entire memory, using the Chip Erase (CE) instruction. This starts an internal Erase cycle
(of duration t_SE t_BE or t_CE). The Erase instruction must be preceded by a Write Enable (WREN)
instruction.
Polling During a Write, Program or Erase Cycle
A further improvement in the time to Write Status Register (WRSR), Program (PP) or Erase (SE, BE or
CE ) can be achieved by not waiting for the worst case delay (t_W, t_PP, t_SE, t_BE or t_CE). The Write In
Progress (WIP) bit is provided in the Status Register so that the application program can monitor its
value, polling it to establish when the previous Write cycle, Program cycle or Erase cycle is complete.
Active Power, Stand-by Power and Deep Power-Down Modes
When Chip Select (CS#) is Low, the device is enabled, and in the Active Power mode. When Chip
Select (CS#) is High, the device is disabled, but could remain in the Active Power mode until all internal
cycles have completed (Program, Erase, Write Status Register). The device then goes into the Stand-
by Power mode. The device consumption drops to I_CC1.
The Deep Power-down mode is entered when the specific instruction (the Enter Deep Power-down
Mode (DP) instruction) is executed. The device consumption drops further to I_CC2. The device remains
in this mode until another specific instruction (the Release from Deep Power-down Mode and Read
Device ID (RDI) instruction) is executed.
All other instructions are ignored while the device is in the Deep Power-down mode. This can be used
as an extra software protection mechanism, when the device is not in active use, to protect the device
from inadvertent Write, Program or Erase instructions.
Status Register. The Status Register contains a number of status and control bits that can be read or
set (as appropriate) by specific instructions.
WIP bit. The Write In Progress (WIP) bit indicates whether the memory is busy with a Write Status
Register, Program or Erase cycle.
WEL bit. The Write Enable Latch (WEL) bit indicates the status of the internal Write Enable Latch.
BP2, BP1, BP0 bits. The Block Protect (BP2, BP1, BP0) bits are non-volatile. They define the size of
the area to be software protected against Program and Erase instructions.
SRP bit / OTP_LOCK bit The Status Register Protect (SRP) bit operates in conjunction with the Write
Protect (WP#) signal. The Status Register Protect (SRP) bit and Write Protect (WP#) signal allow the
device to be put in the Hardware Protected mode. In this mode, the non-volatile bits of the Status
Register (SRP, BP2, BP1, BP0) become read-only bits.
In OTP mode, this bit serves as OTP_LOCK bit, user can read/program/erase OTP sector as normal
sector while OTP_LOCK value is equal 0, after OTP_LOCK is programmed with 1 by WRSR command,
the OTP sector is protected from program and erase operation. The OTP_LOCK bit can only be
programmed once.
Note : In OTP mode, the WRSR command will ignore any input data and program OTP_LOCK bit to 1,
user must clear the protect bits before entering OTP mode and program the OTP code, then execute
WRSR command to lock the OTP sector before leaving OTP mode.
Write Protection
Applications that use non-volatile memory must take into consideration the possibility of noise and other
adverse system conditions that may compromise data integrity. To address this concern the EN25Q16
provides the following data protection mechanisms:
z Power-On Reset and an internal timer (tPUW) can provide protection against inadvertent changes
while the power supply is outside the operating specification.
z Program, Erase and Write Status Register instructions are checked that they consist of a number
of clock pulses that is a multiple of eight, before they are accepted for execution.
This Data Sheet may be revised by subsequent versions
8
or modifications due to changes in technical specifications.
©2004 Eon Silicon Solution, Inc.,
Rev. E, Issue Date: 2009/10/21
www.eonssi.com