DM74LS298 Datasheet, PDF (1/4 Pages) Fairchild Semiconductor – Quad 2-Port Register Multiplexer with Storage

October 1988
Revised March 2000
DM74LS298
Quad 2-Port Register Multiplexer with Storage
General Description
The DM74LS298 is a quad 2-port register. It is the logical
equivalent of a quad 2-input multiplexer followed by a quad
4-bit edge-triggered register. A Common Select input
selects between two 4-bit input ports (data sources). The
selected data is transferred to the output register synchro-
nous with the HIGH-to-LOW transition of the Clock input.
Features
s Select from two data sources
s Fully edge-triggered operation
s Typical power dissipation of 65 mW
Ordering Code:
Order Number Package Number
Package Description
DM74LS298N
N16E
16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide
Logic Symbol
Connection Diagram
V_CC = Pin 16
GND = Pin 8
Pin Descriptions
Pin Names
Description
S
Common Select Inputs
CP
Clock Pulse Input (Active Falling Edge)
I0_a, I0_d
I1_a, I1_d
Q_a, Q_d
Source 0 Data Inputs
Source 1 Data Inputs
Flip-Flip Outputs
Truth Table
Inputs
Output
S
I0_x
I1_x
Q_x
l
l
X
L
l
h
X
H
h
X
l
L
h
X
h
H
l = LOW Voltage Level one setup time prior to the HIGH-to-LOW clock
transition.
h = HIGH Voltage Level one setup time prior to the HIGH-to-LOW clock
transition.
H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial
© 2000 Fairchild Semiconductor Corporation DS009826
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