25AA512
2.10 CHIP ERASE
The CHIP ERASEinstruction will erase all bits (FFh) in
the array. A Write Enable (WREN) instruction must be
given prior to executing a CHIP ERASE. This is done
by setting CS low and then clocking out the proper
instruction into the 25AA512. After all eight bits of the
instruction are transmitted, the CS must be brought
high to set the write enable latch.
The CS pin must be driven high after the eighth bit of
the instruction code has been given or the CHIP
ERASE instruction will not be executed. Once the CS
pin is driven high the self-timed CHIP ERASEinstruc-
tion begins. While the device is executing the CHIP
ERASEinstruction the WIP bit in the STATUS register
can be read to determine when the CHIP ERASE
instruction is complete.
The CHIP ERASEinstruction is entered by driving the
CS low, followed by the instruction code (Figure 2-10)
onto the SI line.
The CHIP ERASEinstruction is ignored if either of the
Block Protect bits (BP0, BP1) are not 0, meaning ¼,
½, or all of the array is protected.
FIGURE 2-10:
CHIP ERASE SEQUENCE
CS
0
1
2
3
4
5
6
7
SCK
1
1
0
0
0
1
1
1
SI
High-Impedance
SO
2010 Microchip Technology Inc.
DS22021F-page 17
MICROCHIP [ MICROCHIP ]
