M29W640FB 데이터 시트보기 (PDF) - STMicroelectronics
부품명
상세내역
제조사
M29W640FB Datasheet PDF : 72 Pages
| |||
M29W640FT, M29W640FB
2 Signal descriptions
2.9 Reset/Block Temporary Unprotect (RP)
The Reset/Block Temporary Unprotect pin can be used to apply a Hardware Reset to the
memory or to temporarily unprotect all Blocks that have been protected.
Note that if VPP/WP is at VIL, then the two outermost boot blocks will remain protected even if
RP is at VID.
A Hardware Reset is achieved by holding Reset/Block Temporary Unprotect Low, VIL, for at
least tPLPX. After Reset/Block Temporary Unprotect goes High, VIH, the memory will be ready
for Bus Read and Bus Write operations after tPHEL or tRHEL, whichever occurs last. See the
Ready/Busy Output section, Table 16: Reset/Block Temporary Unprotect AC Characteristics
and Figure 12: Reset/Block Temporary Unprotect AC Waveforms, for more details.
Holding RP at VID will temporarily unprotect the protected Blocks in the memory. Program and
Erase operations on all blocks will be possible. The transition from VIH to VID must be slower
than tPHPHH.
2.10 Ready/Busy Output (RB)
The Ready/Busy pin is an open-drain output that can be used to identify when the device is
performing a Program or Erase operation. During Program or Erase operations Ready/Busy is
Low, VOL. Ready/Busy is high-impedance during Read mode, Auto Select mode and Erase
Suspend mode.
After a Hardware Reset, Bus Read and Bus Write operations cannot begin until Ready/Busy
becomes high-impedance. See Table 16: Reset/Block Temporary Unprotect AC Characteristics
and Figure 12: Reset/Block Temporary Unprotect AC Waveforms, for more details.
The use of an open-drain output allows the Ready/Busy pins from several memories to be
connected to a single pull-up resistor. A Low will then indicate that one, or more, of the
memories is busy.
2.11 Byte/Word Organization Select (BYTE)
The Byte/Word Organization Select pin is used to switch between the x8 and x16 Bus modes of
the memory. When Byte/Word Organization Select is Low, VIL, the memory is in x8 mode, when
it is High, VIH, the memory is in x16 mode.
2.12
VCC Supply Voltage (2.7V to 3.6V)
VCC provides the power supply for all operations (Read, Program and Erase).
The Command Interface is disabled when the VCC Supply Voltage is less than the Lockout
Voltage, VLKO. This prevents Bus Write operations from accidentally damaging the data during
power up, power down and power surges. If the Program/Erase Controller is programming or
erasing during this time then the operation aborts and the memory contents being altered will
be invalid.
A 0.1µF capacitor should be connected between the VCC Supply Voltage pin and the VSS
Ground pin to decouple the current surges from the power supply. The PCB track widths must
be sufficient to carry the currents required during Program and Erase operations, ICC3.
13/72
Share Link: 