UPD448012-X Datasheet, PDF (4/24 Pages) NEC – 8M-BIT CMOS STATIC RAM 512K-WORD BY 16-BIT EXTENDED TEMPERATURE OPERATION

Block Diagram
VCC
GND
A0
A18
I/O1 - I/O8
I/O9 - I/O16
µPD448012-X
Address
buffer
Row
decoder
Memory cell array
8,388,608 bits
Input data
controller
Sense amplifier /
Switching circuit
Column decoder
Address buffer
Output data
controller
/CE1
CE2
/LB
/UB
/WE
/OE
Truth Table
/CE1 CE2 /OE /WE /LB /UB
Mode
I/O
I/O1 - I/O8
I/O9 - I/O16
Supply current
H
×
×
×
×
×
Not selected High impedance High impedance
ISB
×
L
×
×
×
×
L
H
H
H
×
×
Output disable High impedance High impedance
ICCA
L
H
L
L
Word read
DOUT
DOUT
L
H Lower byte read
DOUT
High impedance
H
L Upper byte read High impedance
DOUT
×
L
L
L
Word write
DIN
DIN
L
H Lower byte write
DIN
High impedance
H
L Upper byte write High impedance
DIN
×
×
×
×
H
H
Not selected High impedance High impedance
ISB
Remark × : VIH or VIL
4
Data Sheet M14466EJ5V0DS