25A512
DS22237C-page 18 Preliminary 2010-2011 Microchip Technology Inc.
2.11 DEEP POWER-DOWN MODE
Deep Power-Down mode of the 25A512 is its lowest
power consumption state. The device will not respond
to any of the Read or Write commands while in Deep
Power-Down mode, and therefore it can be used as an
additional software write protection feature.
The Deep Power-Down mode is entered by driving C
S
low, followed by the instruction code (Figure 2-11) onto
the SI line, followed by driving CS
high.
If the CS
pin is not driven high after the eighth bit of the
instruction code has been given, the device will not
execute Deep power-down. Once the CS line is driven
high there is a delay (T
DP
) before the current settles to
its lowest consumption.
All instructions given during Deep Power-Down mode
are ignored except the Read Electronic Signature
command (RDID). The RDID command will release
the device from Deep power-down and outputs the
electronic signature on the SO pin, and then returns
the device to Standby mode after delay (T
REL
)
Deep Power-Down mode automatically releases at
device power-down. Once power is restored to the
device it will power-up in the Standby mode.
FIGURE 2-11: DEEP POWER-DOWN SEQUENCE
SCK
0 2345671
SI
High-Impedance
SO
CS
100111 10
