Philips 74HCT147N, 74HCT147U, 74HC147U, 74HC147N, 74HC147DB Datasheet

DATA SH EET

Product specification
File under Integrated Circuits, IC06

December 1990

INTEGRATED CIRCUITS

74HC/HCT147

10-to-4 line priority encoder

For a complete data sheet, please also download:

•The IC06 74HC/HCT/HCU/HCMOS Logic Family Specifications

•The IC06 74HC/HCT/HCU/HCMOS Logic Package Information

•The IC06 74HC/HCT/HCU/HCMOS Logic Package Outlines

December 1990 2

Philips Semiconductors Product specification

10-to-4 line priority encoder 74HC/HCT147

FEATURES

• Encodes 10-line decimal to 4-line BCD

• Useful for 10-position switch encoding

• Used in code converters and generators

• Output capability: standard

• ICCcategory: MSI

GENERAL DESCRIPTION

The 74HC/HCT147 are high-speed Si-gate CMOS devices
and are pin compatible with low power Schottky TTL
(LSTTL). They are specified in compliance with JEDEC
standard no. 7A.

The 74HC/HCT147 9-input priority encoders accept data
from nine active LOW inputs (A0to A8) and provide a
binary representation on the four active LOW outputs
(Y0to Y3). A priority is assigned to each input so that when
two or more inputs are simultaneously active, the input
with the highest priority is represented on the output, with
input line A8having the highest priority.

The devices provide the 10-line to 4-line priority encoding
function by use of the implied decimal “zero”. The “zero” is
encoded when all nine data inputs are HIGH, forcing all
four outputs HIGH.

QUICK REFERENCE DATA

GND = 0 V; T

amb

= 25 °C; tr= tf= 6 ns

Notes

1. C

PD

is used to determine the dynamic power dissipation (PDin µW):

PD= CPD× V

CC

2

× fi+∑(CL× V

CC

2

× fo) where:
fi= input frequency in MHz
fo= output frequency in MHz
∑ (CL× V

CC

2

× fo) = sum of outputs
CL= output load capacitance in pF
VCC= supply voltage in V

2. For HC the condition is VI= GND to V

CC

For HCT the condition is VI= GND to VCC− 1.5 V

ORDERING INFORMATION

See

“74HC/HCT/HCU/HCMOS Logic Package Information”

.

SYMBOL PARAMETER CONDITIONS

TYPICAL

UNIT

HC HCT

t

PHL

/ t

PLH

propagation delay Anto Y

n

CL= 15 pF; VCC= 5 V 15 17 ns

C

I

input capacitance 3.5 3.5 pF

C

PD

power dissipation capacitance per package notes 1 and 2 30 33 pF

December 1990 3

Philips Semiconductors Product specification

10-to-4 line priority encoder 74HC/HCT147

PIN DESCRIPTION

PIN NO. SYMBOL NAME AND FUNCTION

8 GND ground (0 V)
9, 7, 6, 14

Y0to Y3BCD address outputs (active LOW)

11, 12, 13, 1, 2, 3, 4, 5, 10

A0to A8decimal data inputs (active LOW)
15 n.c. not connected
16 V

CC

positive supply voltage

Fig.1 Pin configuration. Fig.2 Logic symbol.

Fig.3 IEC logic symbol.