25AA512/25LC512
2.11 DEEP POWER-DOWN MODE
Deep Power-Down mode of the 25XX512 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.
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 (TREL
)
The Deep Power-Down mode is entered by driving CS
low, followed by the instruction code (Figure 2-11) onto
the SI line, followed by driving CS high.
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.
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 (TDP) before the current settles to
its lowest consumption.
FIGURE 2-11:
DEEP POWER-DOWN SEQUENCE
CS
0
1
2
3
4
5
6
7
SCK
1
0
1
1
1
0
0
1
SI
High-Impedance
SO
© 2007 Microchip Technology Inc.
Preliminary
DS22021B-page 17
MICROCHIP [ MICROCHIP ]
