n25q256 Numonyx, n25q256 Datasheet - Page 18

• Manufacturer Part Number: n25q256
• Description: 256-mbit 3 V, Multiple I/o, 4-kbyte Subsector Erase, Xip Enabled, Serial Flash Memory With 108 Mhz Spi Bus Interface
• Manufacturer: Numonyx

Signal descriptions
2.6
2.7
2.8
18/186
Write protect/enhanced program supply voltage (W/VPP),
DQ2
W/VPP/DQ2 can be used as:
When the device is operated in Extended SPI protocol with single or dual instructions, the
two functions W or VPP are selected by the voltage range applied to the pin. If the W/VPP
input is kept in a low voltage range (0 V to VCC) the pin is seen as a control input. This input
signal is used to freeze the size of the area of memory that is protected against program or
erase instructions (as specified by the values in the BP[0:3] bits of the Status Register. (See
Table 3.: Status register
If VPP is in the range of VPPH, it acts as an additional power supply during the Program or
Erase cycles (See
the Program or Erase algorithm is completed.
During the Extended SPI protocol, the QOFR and QIOFR instructions, and the QIO-SPI
protocol instructions, the pin W/VPP/DQ2 is used as an input/output (DQ2 functionality).
Using the Extended SPI protocol the QIFP, QIEFP and the QIO-SPI Program/Erase
instructions, it is still possible to use the VPP additional power supply to speed up internal
operations. However, to enable this possibility it is necessary to set bit 3 of the Volatile
Enhanced Configuration Register to 0.
In this case the W/VPP/DQ2 pin is used as an I/O pin until the end of the instruction
sequence. After the last input data is shifted in, the application should apply VPP voltage to
W/VPP/DQ2 within 200 ms to speed up the internal operations. If the VPP voltage is not
applied within 200 ms the Program/Erase operations start with standard speed.
The default value of the VECR bit 3 is 1, and the VPP functionality for Quad I/O modify
instruction is disabled.
V
V
V
V
CC
SS
CC
SS
is the reference for the V
is the supply voltage.
A protection control input.
A power supply pin.
I/O in Extended SPI protocol quad instructions and in QIO-SPI protocol instructions.
ground
supply voltage
Table 30.: Operating
format).
CC
supply voltage.
Micron Technology, Inc., reserves the right to change products or specifications without notice.
conditions). In this case VPP must be stable until
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N25Q256 - 3 V