54abt574 National Semiconductor Corporation, 54abt574 Datasheet - Page 2

• Manufacturer Part Number: 54abt574
• Description: Octal D-type Flip-flop With Tri-state Outputs
• Manufacturer: National Semiconductor Corporation

www.national.com
Functional Description
The ’ABT574 consists of eight edge-triggered flip-flops with
individual D-type inputs and TRI-STATE true outputs. The
buffered clock and buffered Output Enable are common to all
flip-flops. The eight flip-flops will store the state of their indi-
vidual D inputs that meet the setup and hold times require-
ments on the LOW-to-HIGH Clock (CP) transition. With the
Output Enable (OE) LOW, the contents of the eight flip-flops
are available at the outputs. When OE is HIGH, the outputs
are in a high impedance state. Operation of the OE input
does not affect the state of the flip-flops.
Function Table
Logic Diagram
Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays.
OE
H
Inputs
H or L
CP
D
L
Internal Outputs
NC
Q
O
Z
Hold
Function
2
H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial
Z = High Impedance
N
NC = No Change
OE
H
H
H
L
L
L
L
= LOW-to-HIGH Transition
Inputs
H or L
H or L
H or L
CP
N
N
N
N
D
H
H
H
H
L
L
L
Internal Outputs
NC
NC
NC
Q
H
H
L
L
NC
NC
O
H
Z
Z
Z
L
Hold
Load
Load
Data Available
Data Available
No Change in Data
No Change in Data
Function
DS100208-3