Datasheet DM74LS273WMX, DM74LS273WM, DM74LS273SJX, DM74LS273SJ, DM74LS273N Datasheet (Fairchild Semiconductor)

© 2000 Fairchild Semiconductor Corporation DS009825 www.fairchildsemi.com

October 1988
Revised March 2000

DM74LS273 8-Bit Register with Clear

DM74LS273
8-Bit Register with Clear

General Description

The DM74LS273 is a high speed 8 -bit register, consisting
of eight D-type flip-flops with a common Clock and an
asynchronous active LOW Master Reset. This device is
supplied in a 20-pin packa ge featuring 0 .3 inch row spac­ing.

Features

■ Edge-triggered

■ 8-bit high speed register

■ Parallel in and out

■ Common clock and master reset

Ordering Code:

Devices also availab le in Tape and Reel. Specify by appending th e s uffix let t er “X” to the ordering code.

Logic Symbol

VCC = Pin 20
GND = Pin 10

Pin Descriptions

Connection Diagram

Truth T able

H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial

Order Number Package Number Package Description

DM74LS273WM M20B 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide
DM74LS273SJ M20D 20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide
DM74LS273N N20A 20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide

Pin Names Description

CP Clock Pulse Input (Active Rising Edge)

D0–D7 Data Inputs
MR

Asynchronous Master Reset Input (Active LOW)

Q0–Q7 Flip-Flop Outputs

Inputs Outputs

MR CP D

n

Q

n

LXXL
H



HH

H



LL

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DM74LS273

Functional Description

The DM74LS273 is an 8-bit parallel register with a common
Clock and common Master Reset. Whe n the MR

input is
LOW, the Q outputs are LOW, independent of the other
inputs. Information meeting the setup and hold time
requirements of the D inputs is transferred t o the Q outputs
on the LOW-to-HIGH transition of the clock input.

Logic Diagram

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DM74LS273

Absolute Maximum Ratings(Note 1)

Note 1: The “Absolute Maximum Ratings ” are those val ues beyond w hich

the safety of the device cannot be guaranteed. The device should not be
operated at these limits. The parametric values defined in the Electrical
Characteristics tables are not guaranteed at the absolute maximum ratings.
The “Recommend ed O peratin g Cond itions” t able w ill defin e the condition s
for actual device operation.

Recommended Operating Conditions

Electrical Characteristics

Over recommended operating free air temperature range (unless otherwise noted)

Note 2: All typicals are at VCC = 5V, TA = 25°C.
Note 3: Not more than one output should be shorted at a time, and the duration should not exceed one second.

Switching Characteristics

VCC = +5.0V, TA =+25°C

Supply Voltage 7V
Input Voltage 7V
Operating Free Air Temperature Range 0°C to +70°C
Storage Temperature Range −65°C to +150°C

Symbol Parameter Min Nom Max Units

V

CC

Supply Voltage 4.75 5 5.25 V

V

IH

HIGH Level Input Voltage 2 V

V

IL

LOW Level Input Voltage 0.8 V

I

OH

HIGH Level Output Current −0.4 mA

I

OL

LOW Level Output Current 8 mA

T

A

Free Air Operating Tempe rature 0 70 °C

t

S

(H) Setup Time HIGH or LOW 15

ns

t

S

(L) Dn to CP 15

t

H

(H) Hold Time HIGH or LOW 5

ns

t

H

(L) Dn to CP 5

t

W

(H) CP Pulse Width HIGH or LOW 20

ns

t

W

(L) 20

t

W

(L) MR Pulse Width LOW 20 ns

t

REC

Recovery Time

15 ns

MR

to CP

Symbol Parameter Conditions Min

Typ

Max Units

(Note 2)

V

I

Input Clamp Voltage VCC = Min, II = −18 mA −1.5 V

V

OH

HIGH Level VCC = Min, IOH = Max,

2.7 3.4 V

Output Voltage VIL = Max

V

OL

LOW Level VCC = Min, IOL = Max,

0.35 0.5

Output Voltage VIH = Min V

IOL = 4 mA, VCC = Min 0.25 0.4

I

I

Input Current @ Max Input Voltage VCC = Max, VI = 7V 0.1 mA

I

IH

HIGH Level Input Current VCC = Max, VI = 2.7V 20 µA

I

IL

LOW Level Input Current VCC = Max, VI = 0.4V −0.4 mA

I

OS

Short Circuit Output Current VCC = Max (Note 3) −20 −100 mA

I

CC

Supply Current VCC = Max 27 mA

Symbol Parameter

CL = 15 pF

UnitsRL = 2 kΩ

Min Max

f

MAX

Maximum Clock Frequency 30 MHz

t

PLH

Propagation Delay 24

ns

t

PHL

CP to Q

n

24

t

PLH

Propagation Delay

27 ns

MR to Q

n

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DM74LS273

Physical Dimensions inches (millimeters) unless otherwise noted

20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide

Package Number M20B

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DM74LS273

Physical Dimensions inches (millimeters) unless otherwise noted (Continued)

20-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide

Package Number M20D

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DM74LS273 8-Bit Register with Clear

Physical Dimensions inches (millimeters) unless otherwise noted (Continued)

20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide

Package Number N20A

Fairchild does not assume any responsibility for use of any circuitry described, no circuit pate nt licenses are implied and
Fairchild reserves the right at any time without notice to change said circuitry and specifications.

LIFE SUPPORT POLICY

FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT
DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD
SEMICONDUCTOR CORPORATION. As used herein:

1. Life support devices or systems are devices or syste ms

which, (a) are intended for surgical implant into the
body, or (b) support or sustain life, and (c) whose failure
to perform when properly used in accordance with
instructions for use provided in the labeling, can be rea­sonably expected to result in a significant inju ry to the
user.

2. A critical component i n any compon ent of a lif e support
device or system whose failu re to perform can be rea­sonably expected to ca use the fa i lure of the life su pp ort
device or system, or to affect its safety or effectiveness.

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