Philips 74hc hct147 DATASHEETS

INTEGRATED CIRCUITS

DATA SH EET

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

74HC/HCT147

10-to-4 line priority encoder

Product specification
File under Integrated Circuits, IC06

December 1990

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

= 25 °C; tr= tf= 6 ns

amb

SYMBOL PARAMETER CONDITIONS

t

PHL

C
C

I
PD

/ t

PLH

propagation delay Anto Y

n

CL= 15 pF; VCC= 5 V 15 17 ns
input capacitance 3.5 3.5 pF
power dissipation capacitance per package notes 1 and 2 30 33 pF

TYPICAL

UNIT

HC HCT

Notes

1. C

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

PD

PD= CPD× V

2

× fi+∑(CL× V

CC

2

× fo) where:

CC

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

2

× fo) = sum of outputs

CC

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

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

See

.

December 1990 2

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
11, 12, 13, 1, 2, 3, 4, 5, 10
15 n.c. not connected
16 V

Y0to Y3BCD address outputs (active LOW)
A0to A8decimal data inputs (active LOW)

CC

positive supply voltage

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

Fig.3 IEC logic symbol.

December 1990 3