74HC7403 Datasheet, PDF (23/28 Pages) NXP Semiconductors – 4-Bit x 64-word FIFO register; 3-state

Philips Semiconductors
4-Bit x 64-word FIFO register; 3-state
Product specification
74HC/HCT7403
handbook, full pagewidth
composite
DIR
QD
74
CP
Q
QD
CP
QR
4
SI
MR
4
Dn
Qn 4
DIR DOR
7403
SI
SO
MR
OE
DIR DOR
SI
SO
SO
7403
MR
OE
OE
Dn
Qn ⁴
DQ
74
CP
Q
DQ
CP
RQ
MGA683
composite
DOR
Fig.19 Expanded FIFO for increased word length.
Note to Fig.19
This circuit is only required if the SI input is constantly held HIGH, when the FIFO is empty and the automatic shift-in
cycles are started or if SO output is constantly held HIGH, when the FIFO is full and the automatic shift-out cycles are
started (see Figs 7 and 10).
September 1993
23