SN54273, SN54LS273, SN74273, SN74LS273
OCTAL D-TYPE FLIP-FLOP WITH CLEAR
SDLS090 – OCTOBER 1976 – REVISED MARCH 1988
•
•
•
•
Contains Eight Flip-Flops With Single-Rail
Outputs
Buffered Clock and Direct Clear Inputs
Individual Data Input to Each Flip-Flop
Applications Include:
Buffer/Storage Registers
Shift Registers
Pattern Generators
SN54273, SN74LS273 . . . J OR W PACKAGE
SN74273 . . . N PACKAGE
SN74LS273 . . . DW OR N PACKAGE
(TOP VIEW)
CLR
1Q
1D
2D
2Q
3Q
3D
4D
4Q
GND
description
These monolithic, positive-edge-triggered flipflops utilize TTL circuitry to implement D-type
flip-flop logic with a direct clear input.
Information at the D inputs meeting the setup time
requirements is transferred to the Q outputs on the
positive-going edge of the clock pulse. Clock
triggering occurs at a particular voltage level and
is not directly related to the transition time of the
positive-going pulse. When the clock input is at
either the high or low level, the D input signal has
no effect ar the output.
19
3
18
4
17
5
16
6
15
7
14
8
13
9
12
10
VCC
8Q
8D
7D
7Q
6Q
6D
5D
5Q
CLK
20
2
11
1D
1Q
CLR
V CC
8Q
SN54LS273 . . . FK PACKAGE
(TOP VIEW)
2D
2Q
3Q
3D
4D
4
3 2 1 20 19
18
5
17
6
16
7
15
8
14
9 10 11 12 13
8D
7D
7Q
6Q
6D
4Q
GND
CLK
5Q
5D
These flip-flops are guaranteed to respond to
clock frequencies ranging form 0 to 30 megahertz
while maximum clock frequency is typically 40
megahertz. Typical power dissipation is 39
milliwatts per flip-flop for the ′273 and 10 milliwatts
for the ′LS273.
logic symbol†
FUNCTION TABLE
(each flip-flop)
INPUTS
1
CLEAR
CLOCK
D
OUTPUT
Q
L
X
X
L
H
↑
H
H
H
↑
L
L
X
CLK
1D
L
H
CLR
Q0
2D
3D
4D
5D
6D
7D
8D
1
11
3
4
EN
C1
1D
2
5
7
6
8
9
13
12
14
15
17
16
18
19
1Q
2Q
3Q
4Q
5Q
6Q
7Q
8Q
† This symbol is in accordance with ANSI/IEEE Std.
91-1984 and IEC Publication 617-12.
Pin numbers shown are for the DW, J, N, and W packages.
Copyright © 1988, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
1
