upd43256b-x Renesas Electronics Corporation., upd43256b-x Datasheet - Page 12

• Manufacturer Part Number: upd43256b-x
• Description: 256k-bit Cmos Static Ram 32k-word By 8-bit Extended Temperature Operation
• Manufacturer: Renesas Electronics Corporation.

Write Cycle Timing Chart 1 (/WE Controlled)
Cautions 1. /CS or /WE should be fixed to high level during address transition.
Remarks 1. Write operation is done during the overlap time of a low level /CS and a low level /WE.
12
I/O (Input / Output)
Address (Input)
2. When I/O pins are in the output state, do not apply to the I/O pins signals that are
2. When /WE is at low level, the I/O pins are always high impedance. When /WE is at high level,
3. If /CS changes to low level at the same time or after the change of /WE to low level, the I/O pins
/WE (Input)
/CS (Input)
read operation is executed. Therefore /OE should be at high level to make the I/O pins high impedance.
will remain high impedance state.
opposite in phase with output signals.
Indefinite data out
t
AS
Data Sheet M11012EJ6V0DS
t
WHZ
t
AW
t
CW
t
WC
impe-
dance
High
t
WP
t
DW
Data in
t
t
WR
DH
t
OW
High
impe-
dance
Indefinite data out
μ
PD43256B-X