HY29F400 Hynix Semiconductor, HY29F400 Datasheet - Page 19

• Manufacturer Part Number: HY29F400
• Description: 4 Megabit (512Kx8/256Kx16) 5 Volt-only Flash Memory
• Manufacturer: Hynix Semiconductor

Write Pulse “Glitch” Protection
Noise pulses of less than 5 ns (typical) on OE#,
CE# or WE# do not initiate a write cycle.
Logical Inhibit
Write cycles are inhibited by asserting any one of
the following conditions: OE# = V
WE# = V
must be a logical zero while OE# is a logical one.
Rev. 5.2/May 01
IH
. To initiate a write cycle, CE# and WE#
IL
, CE# = V
IH
, or
Power-Up Write Inhibit
If WE# = CE# = V
up, the device does not accept commands on the
rising edge of WE#. The internal state machine is
automatically reset to the Read mode on power-
up.
Sector Protection
Additional data protection is provided by the
HY29F400’s sector protect feature, described pre-
viously, which can be used to protect sensitive
areas of the Flash array from accidental or unau-
thorized attempts to alter the data.
IL
and OE# = V
IH
during power
HY29F400
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