NSC 54F373LMQB, 54F373FMQB, 54F373DMQB, 54F373DC Datasheet

TL/F/9523

54F/74F373 Octal Transparent Latch with TRI-STATE Outputs

May 1995

54F/74F373
Octal Transparent Latch with TRI-STATE

É

Outputs

General Description

The ’F373 consists of eight latches with TRI-STATE outputs
for bus organized system applications. The flip-flops appear
transparent to the data when Latch Enable (LE) is HIGH.
When LE is LOW, the data that meets the setup times is
latched. Data appears on the bus when the Output Enable
(OE

) is LOW. When OE is HIGH the bus output is in the high

impedance state.

Features

Y

Eight latches in a single package

Y

TRI-STATE outputs for bus interfacing

Y

Guaranteed 4000V minimum ESD protection

Commercial Military

Package

Package Description

Number

74F373PC N20A 20-Lead (0.300×Wide) Molded Dual-In-Line

54F373DM (QB) J20A 20-Lead Ceramic Dual-In-Line

74F373SC (Note 1) M20B 20-Lead (0.300×Wide) Molded Small Outline, JEDEC

74F373SJ (Note 1) M20D 20-Lead (0.300×Wide) Molded Small Outline, EIAJ

74F373MSA (Note 1) MSA20 20-Lead Molded Shrink Small Outline, EIAJ Type II

54F373FM (QB) W20A 20-Lead Cerpack

54F373LM (QB) E20A 20-Lead Ceramic Leadless Chip Carrier, Type C

Note 1: Devices also available in 13×reel. Use suffixeSCX, SJX, and MSAX.

Logic Symbols Connection Diagrams

IEEE/IEC

TL/F/9523– 4

TL/F/9523– 1

Pin Assignment

for DIP, SOIC, SSOP and Flatpak

TL/F/9523– 2

Pin Assignment

for LCC

TL/F/9523– 3

TRI-STATEÉis a registered trademark of National Semiconductor Corporation.

C

1995 National Semiconductor Corporation RRD-B30M75/Printed in U. S. A.

Unit Loading/Fan Out

54F/74F

Pin Names Description

U.L. Input I

IH/IIL

HIGH/LOW Output IOH/I

OL

D0–D

7

Data Inputs 1.0/1.0 20 mA/b0.6 mA

LE Latch Enable Input (Active HIGH) 1.0/1.0 20 mA/

b

0.6 mA

OE

Output Enable Input (Active LOW) 1.0/1.0 20 m A/b0.6 mA

O0–O

7

TRI-STATE Latch Outputs 150/40 (33.3)b3 mA/24 mA (20 mA)

Functional Description

The ’F373 contains eight D-type latches with TRI-STATE
output buffers. When the Latch Enable (LE) input is HIGH,
data on the D

n

inputs enters the latches. In this condition
the latches are transparent, i.e., a latch output will change
state each time its D input changes. When LE is LOW, the
latches store the information that was present on the D in­puts a setup time preceding the HIGH-to-LOW transition of
LE. The TRI-STATE buffers are controlled by the Output
Enable (OE

) input. When OE is LOW, the buffers are in the

bi-state mode. When OE

is HIGH the buffers are in the high
impedance mode but this does not interfere with entering
new data into the latches.

Truth Table

Inputs Output

LE OE D

n

O

n

HLH H
HLL L
LLXO

n

(no change)

XHX Z

H

e

HIGH Voltage Level

L

e

LOW Voltage Level

X

e

Immaterial

Z

e

High Impedance State

Logic Diagram

TL/F/9523– 5

Please note that this diagram is provided only for the understanding of logic operations and should not be used to estimate propagation delays.

2

Absolute Maximum Ratings (Note 1)

If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales
Office/Distributors for availability and specifications.

Storage Temperature

b

65§Ctoa150§C

Ambient Temperature under Bias

b

55§Ctoa125§C

Junction Temperature under Bias

b

55§Ctoa175§C

Plastic

b

55§Ctoa150§C

V

CC

Pin Potential to

Ground Pin

b

0.5V toa7.0V

Input Voltage (Note 2)

b

0.5V toa7.0V

Input Current (Note 2)

b

30 mA toa5.0 mA

Note 1: Absolute maximum ratings are values beyond which the device may
be damaged or have its useful life impaired. Functional operation under
these conditions is not implied.

Note 2: Either voltage limit or current limit is sufficient to protect inputs.

Voltage Applied to Output

in HIGH State (with V

CC

e

0V)

Standard Output

b

0.5V to V

CC

TRI-STATE Output

b

0.5V toa5.5V

Current Applied to Output

in LOW State (Max) twice the rated I

OL

(mA)

ESD Last Passing Voltage (Min) 4000V

Recommended Operating
Conditions

Free Air Ambient Temperature

Military

b

55§Ctoa125§C

Commercial 0

§

Ctoa70§C

Supply Voltage

Military

a

4.5V toa5.5V

Commercial

a

4.5V toa5.5V

DC Electrical Characteristics

Symbol Parameter

54F/74F

Units V

CC

Conditions

Min Typ Max

V

IH

Input HIGH Voltage 2.0 V Recognized as a HIGH Signal

V

IL

Input LOW Voltage 0.8 V Recognized as a LOW Signal

V

CD

Input Clamp Diode Voltage

b

1.2 V Min I

IN

eb

18 mA

V

OH

Output HIGH 54F 10% V

CC

2.5 I

OH

eb

1mA

Voltage 54F 10% V

CC

2.4 I

OH

eb

3mA

74F 10% V

CC

2.5
V Min

I

OH

eb

1mA

74F 10% V

CC

2.4 I

OH

eb

3mA

74F 5% V

CC

2.7 I

OH

eb

1mA

74F 5% V

CC

2.7 I

OH

eb

3mA

V

OL

Output LOW 54F 10% V

CC

0.5
V Min

I

OL

e

20 mA

Voltage 74F 10% V

CC

0.5 I

OL

e

24 mA

I

IH

Input HIGH Current 54F 20.0

mA Max V

IN

e

2.7V

74F 5.0

I

BVI

Input HIGH Current 54F 100

mA Max V

IN

e

7.0V

Breakdown Test 74F 7.0

I

CEX

Output HIGH 54F 250

mA Max V

OUT

e

V

CC

Leakage Current 74F 50

V

ID

Input Leakage

74F 4.75 V 0.0

I

ID

e

1.9 mA

Test All Other Pins Grounded

I

OD

Output Leakage

74F 3.75 mA 0.0

V

IOD

e

150 mV

Circuit Current All Other Pins Grounded

I

IL

Input LOW Current

b

0.6 mA Max V

IN

e

0.5V

I

OZH

Output Leakage Current 50 mA Max V

OUT

e

2.7V

I

OZL

Output Leakage Current

b

50 mA Max V

OUT

e

0.5V

I

OS

Output Short-Circuit Current

b

60

b

150 mA Max V

OUT

e

0V

I

ZZ

Bus Drainage Test 500 mA 0.0V V

OUT

e

5.25V

I

CCZ

Power Supply Current 38 55 mA Max V

O

e

HIGH Z

3