A25L032 Series
(December, 2014, Version 1.5) 6 AMIC Technology Corp.
OPERATING FEATURES
Page Programming
To program one data byte, two instructions are required: Write
Enable (WREN), which is one byte, and a Page Program (PP)
sequence, which consists of four bytes plus data. This is
followed by the internal Program cycle (of duration tPP).
To spread this overhead, the Page Program (PP) instruction
allows up to 256 bytes to be programmed at a time (changing
bits from 1 to 0), provided that they lie in consecutive
addresses on the same page of memory.
Dual Input Fast Program
The Dual Input Fast Program (DIFP) instruction makes it
possible to program up to 256 bytes using two input pins at
the same time (by changing bits from 1 to 0).
For optimized timings, it is recommended to use the Dual
Input Fast Program (DIFP) instruction to program all
consecutive targeted bytes in a single sequence rather to
using several Dual Input Fast Program (DIFP) sequences
each containing only a few bytes.
Sector Erase, Block Erase, and Chip Erase
The Page Program (PP) instruction and Dual Input Fast
Program (DIFP) instruction allow bits to be reset from 1 to 0.
Before this can be applied, the bytes of memory need to have
been erased to all 1s (FFh). This can be achieved, a sector at
a time, using the Sector Erase (SE) instruction, a block at a
time, using the Block Erase (BE) instruction, or throughout the
entire memory, using the Chip Erase (CE) instruction. This
starts an internal Erase cycle (of duration tSE, tBE, or tCE).
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 OTP (POTP), Program (PP, DIFP), or
Erase (SE, BE, or CE) can be achieved by not waiting for the
worst case delay (tW, tPP, tSE, tBE, tCE). 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 ( S) is Low, the device is enabled, and in
the Active Power mode.
When Chip Select ( S) 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 in to the Stand-by Power mode. The device
consumption drops to ICC1.
The Deep Power-down mode is entered when the specific
instruction (the Deep Power-down Mode (DP) instruction) is
executed. The device consumption drops further to ICC2. The
device remains in this mode until another specific instruction
(the Release from Deep Power-down Mode and Read
Electronic Signature (RES) 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. See Read Status Register (RDSR) for a detailed
description of the Status Register bits.
Protection Modes
The environments where non-volatile memory devices are
used can be very noisy. No SPI device can operate correctly
in the presence of excessive noise. To help combat this, the
A25L032 boasts the following data protection mechanisms:
Power-On Reset and an internal timer (tPUW) can provide
protection against inadvertent changes while the power
supply is outside the operating specification.
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.
All instructions that modify data must be preceded by a
Write Enable (WREN) instruction to set the Write Enable
Latch (WEL) bit. This bit is returned to its reset state by
the following events:
- Power-up
- Write Disable (WRDI) instruction completion
- Write Status Register (WRSR) instruction completion
- Program OTP (POTP) instruction completion
- Page Program (PP) instruction completion
- Dual Input Fast Program (DIFP) instruction completion
- Sector Erase (SE) instruction completion
- Block Erase (BE) instruction completion
- Chip Erase (CE) instruction completion
The Block Protect (BP2, BP1, BP0) bits conjunction with
Sector Protect (SEC) bit , Top/Bottom (TB) bit and
Complement Protect (CMP) bit allow part of the memory to
be configured as read-only. This is the Software Protected
Mode (SPM).
The Write Protect ( W) signal allows the Block Protect
(BP2, BP1, BP0) bits, Sector Protect (SEC) bit,
Top/Bottom (TB) bit, All Protect (APT), Complement
Protect (CMP) bit and Status Register Protect (SRP1,
SRP0) bits to be protected. This is the Hardware
Protected Mode (HPM).
In addition to the low power consumption feature, the
Deep Power-down mode offers extra software protection
from inadvertent Write, Program and Erase instructions, as
all instructions are ignored except one particular instruction
(the Release from Deep Power-down instruction).