HY29F400A Datasheet, PDF (4/40 Pages) Hynix Semiconductor – 4 Megabit (512Kx8/256Kx16) 5 Volt-only Flash Memory

HY29F400A
SIGNAL DESCRIPTIONS
Name
Type
Description
A[17:0]
Inputs
Address, active High. In Word mode, these 18 inputs select one of 262,144
(256K) words within the array for read or write operations. In Byte mode, these
inputs are combined with the DQ15/A-1 input (LSB) to select one of 524,288
(512K) bytes within the array for read or write operations.
DQ[15]/A[-1],
DQ[14:0]
Data Bus, active High. In Word mode, these pins provide a 16-bit data path
Inputs/Outputs for read and write operations. In Byte mode, DQ[7:0] provide an 8-bit data path
Tri-state and DQ[15]/A[-1] is used as the LSB of the 19-bit byte address input. DQ[14:8]
are unused and remain tri-stated in Byte mode.
BYTE#
Input
Byte Mode, active Low. Controls the Byte/Word configuration of the device.
Low selects Byte mode, High selects Word mode.
CE#
Input
Chip Enable, active Low. This input must be asserted to read data from or
write data to the HY29F400A. When High, the data bus is tri-stated and the
device is placed in the Standby mode.
OE#
Input
Output Enable, active Low. This input must be asserted for read operations
and negated for write operations. BYTE# determines whether a byte or a word
is read during the read operation. When High, data outputs from the device are
disabled and the data bus pins are placed in the high impedance state.
WE#
Input
Write Enable, active Low. Controls writing of commands or command
sequences in order to program data or erase sectors of the memory array. A
write operation takes place when WE# is asserted while CE# is Low and OE#
is High. BYTE# determines whether a byte or a word is written during the write
operation.
RESET#
Input
Hardware Reset, active Low. Provides a hardware method of resetting the
HY29F400A to the read array state. When the device is reset, it immediately
terminates any operation in progress. The data bus is tri-stated and all read/write
commands are ignored while the input is asserted. While RESET# is asserted,
the device will be in the Standby mode.
RY/BY#
Output
Open Drain
Ready/Busy Status. Indicates whether a write or erase command is in
progress or has been completed. RY/BY# is valid after the rising edge of the
final WE# pulse of a command sequence. It remains Low while the device is
actively programming data or erasing, and goes High when it is ready to read
array data.
V_CC
--
5-volt (nominal) power supply.
V_SS
--
Power and signal ground.
4
Rev. 1.0/Jan. 02