SA25F005 Saifun, SA25F005 Datasheet - Page 33

• Manufacturer Part Number: SA25F005
• Description: 512Kb Serial Flash
• Manufacturer: Saifun

Powerup and Powerdown
The device must not be selected at
powerup or powerdown (that is, CSb must
follow the voltage applied on V
reaches the correct value, as follows:
A simple pull-up resistor on CSb can
usually be used to insure safe and proper
powerup and powerdown. To avoid data
corruption and inadvertent write operations
during powerup, a Power On Reset (POR)
circuit is included. The logic inside the
device is held at reset while V
than the POR threshold value (V
operations are disabled and the device
does not respond to any instructions.
The device ignores all instructions until a
time delay of t
moment that V
threshold. However, correct operation of
the device is not guaranteed if by this time
V
Register, Program or Erase instructions
should be sent until t
minimum V
= V
= V
CC
further delay of t
Table 11)
is still below V
CC
SS
(min) at powerup, and then for a
at powerdown
CC
threshold after V
PU
CC
CC
has elapsed after the
rises above the VWI
PU
(min). No Write Status
(as described in
PU
reaches the
CC
CC
.
CC
) until V
POR
is less
), all
CC
At powerup, the device is in Standby mode
(not SP mode) and the WEN bit is reset.
Normal precautions must be taken for
supply rail decoupling to stabilize the V
feed. Each device in a system should have
the V
capacitor close to the package pins (this
capacitor is generally of the order of
0.1 µF).
All operations are disabled and the device
does not respond to any instructions when
V
operating voltage to below the V
threshold. (The designer must be aware
that if a powerdown occurs while a Write,
Program or Erase cycle is in progress, data
corruption can result.)
Symbol
CC
V
t
POR
PU
drops
CC
POR Threshold
V
Parameter
CC
rail decoupled by a suitable
(min) to CS
Table 11. Powerup
Value
low
at
SA25F005 Advanced Information
powerdown
Min.
2.2
2
www.DataSheet4U.com
Max .
2.4
from
SAIFUN
Unit
ms
V
the
POR
CC
33