8/12/2019 74hct148

1/11

M54HC148M74HC148

October 1992

8 TO 3 LINE PRIORITY ENCODER

B1R(Plastic Package)

ORDER CODES :M54HC148F1R M74HC148M1RM74HC148B1R M74HC148C1R

F1R(Ceramic Package)

M1R(MicroPackage)

C1R(Chip Carrier)

PIN CONNECTIONS (top view)

NC =No InternalConnection

INPUT AND OUTPUT EQUIVALENT CIRCUIT

DESCRIPTION

. HIGH SPEEDtPD = 15 ns (TYP.) AT V CC = 5 V. LOW POWER DISSIPATIONICC = 4 A (MAX.) AT TA = 25 C. HIGH NOISE IMMUNITYVNIH = VNIL = 28 % V CC (MIN.). OUTPUT DRIVE CAPABILITY10 LSTTL LOADS. SYMMETRICAL OUTPUT IMPEDANCE

IOH = IOL = 4 mA (MIN.)

. BALANCED PROPAGATION DELAYStPLH = tPHL. WIDE OPERATING VOLTAGE RANGEVCC (OPR) = 2 V TO 6 V. PIN AND FUNCTION COMPATIBLEWITH 54/74LS148

The M54/74HC148 is a high speed CMOS 8-TO-3LINE PRIORITY ENCODER fabricated in silicongate C 2MOS technology.It has the same high speed performance for LSTTLcombined with true CMOS low power consumption.The M54/74HC148 encodes eight data lines tothree-line (4-2-1) binary (octal). Cascading circuitry(enable input EI and enable output EO) has beenprovided to allow octal expansion without the needfor external circuitry. Data inputs are active at thelow logic level.All inputs are equipped with protection circuitsagainst static discharge and transient excess volt-age.

1/11

8/12/2019 74hct148

2/11

TRUTH TABLE

INPUTS OUTPUTSE1 0 1 2 3 4 5 6 7 A2 A1 A0 GS E0

H X X X X X X X X H H H H HL H H H H H H H H H H H H LL X X X X X X X L L L L L HL X X X X X X L H L L H L HL X X X X X L H H L H L L HL X X X X L H H H L H H L HL X X X L H H H H H L L L HL X X L H H H H H H LL H L HL X L H H H H H H H H L L HL L H H H H H H H H H H L H

X: DontCare

LOGIC DIAGRAM

M54/M74HC148

2/11

8/12/2019 74hct148

3/11

PIN DESCRIPTION

PIN No SYMBOL NAME AND FUNCTION9, 7, 6 A0 to A2 Data Outputs

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

10

0 to 7 Data Inputs

15 EO Enable Output5 EI Enable Input

14 GS Priority Flag Output8 GND Ground (0V)

16 V CC Positive Supply Voltage

IEC LOGIC SYMBOL

ABSOLUTE MAXIMUM RATINGS

Symbol Parameter Value UnitVCC Supply Voltage -0.5 to +7 VVI DC Input Voltage -0.5 to V CC + 0.5 VVO DC Output Voltage -0.5 to V CC + 0.5 VIIK DC Input Diode Current 20 mAIOK DC Output Diode Current 20 mAIO DC Output Source Sink Current Per Output Pin 25 mA

ICC or IGND DC VCC or Ground Current 50 mA

P D Power Dissipation 500 (*) mWTstg Storage Temperature -65 to +150 oCTL Lead Temperature (10 sec) 300 oC

AbsoluteMaximumRatingsare those values beyond whichdamage to thedevicemay occur. Functional operation under these condition isnot implied.(*) 500 mW: 65 oC derate to 300 mW by 10mW/ oC: 65 oC to85 oC

RECOMMENDED OPERATING CONDITIONS

Symbol Parameter Value UnitVCC Supply Voltage 2 to 6 VVI Input Voltage 0 to V CC VVO Output Voltage 0 to V CC V

Top Operating Temperature: M54HC SeriesM74HC Series -55 to +125-40 to +85

o

CoCtr, tf Input Rise and Fall Time V CC = 2 V 0 to 1000 ns

VCC = 4.5 V 0 to 500VCC = 6 V 0 to 400

M54/M74HC148

3/11

8/12/2019 74hct148

4/11

DC SPECIFICATIONS

Symbol Parameter

Test Conditions Value

UnitVCC(V)

TA = 25 o C

54HC and 74HC

-40 to 85 o C

74HC

-55 to 125 o C

54HCMin. Typ. Max. Min. Max. Min. Max.VIH High Level Input

Voltage2.0 1.5 1.5 1.5

V4.5 3.15 3.15 3.156.0 4.2 4.2 4.2

VIL Low Level InputVoltage

2.0 0.5 0.5 0.5V4.5 1.35 1.35 1.35

6.0 1.8 1.8 1.8VOH High Level

Output Voltage2.0

VI =VIHorVIL

IO=-20 A1.9 2.0 1.9 1.9

V4.5 4.4 4.5 4.4 4.46.0 5.9 6.0 5.9 5.94.5 IO=-4.0 mA 4.18 4.31 4.13 4.10

6.0 IO=-5.2 mA 5.68 5.8 5.63 5.60VOL Low Level Output

Voltage2.0

VI =VIHorVIL

IO= 20 A0.0 0.1 0.1 0.1

V4.5 0.0 0.1 0.1 0.16.0 0.0 0.1 0.1 0.14.5 IO= 4.0 mA 0.17 0.26 0.33 0.406.0 IO= 5.2 mA 0.18 0.26 0.33 0.40

II Input LeakageCurrent 6.0

VI = VCC or GND 0.1 1 1 A

ICC Quiescent SupplyCurrent

6.0 V I = VCC or GND 4 40 80 A

M54/M74HC148

4/11

8/12/2019 74hct148

5/11

AC ELECTRICAL CHARACTERISTICS (C L = 50 pF, Input t r = tf = 6 ns)

Symbol Parameter

Test Conditions Value

UnitVCC(V)

TA = 25 o C

54HC and 74HC

-40 to 85 o C

74HC

-55 to 125 o C

54HCMin. Typ. Max. Min. Max. Min. Max.tTLHtTHL

Output TransitionTime

2.0 30 75 95 110ns4.5 8 15 19 22

6.0 7 13 16 19tPLHtPHL

PropagationDelay Time(In - A0, A1, A2)

2.0 60 150 190 225ns4.5 19 30 38 45

6.0 16 26 32 38tPLHtPHL

PropagationDelay Time(In - EO, GS)

2.0 60 150 190 225ns4.5 19 30 38 45

6.0 16 26 32 38tPLH

tPHLPropagation

Delay Time(EI - EO)

2.0 40 115 145 175

ns4.5 14 23 29 356.0 12 20 25 30

tPLHtPHL

PropagationDelay Time(EI - GS)

2.0 40 115 145 175ns4.5 14 23 29 35

6.0 12 20 25 30tPLHtPHL

PropagationDelay Time(EI - A0, A1, A2)

2.0 40 115 145 175ns4.5 14 23 29 35

6.0 12 20 25 30CIN Input Capacitance 5 10 10 10 pF

CPD (*) Power DissipationCapacitance

60 pF

(*) CPD is defined as the value of the ICs internal equivalent capacitance which is calculated from the operating current consumption without load.

(Refer to Test Circuit). Average operting current can be obtained by the followingequation. I CC(opr) = C PD VCC fIN + ICC

INPUT WAVEFORM IS THE SAME AS THATIN CASE OFSWITCHINGCHARACTERISTICS TEST.

SWITCHING CHARACTERISTICS TESTCIRCUIT

TEST CIRCUIT I CC (Opr.)

M54/M74HC148

5/11

8/12/2019 74hct148

6/11

TYPICAL APPLICATION

4-BIT CASCADECONNECTION

M54/M74HC148

6/11

8/12/2019 74hct148

7/11

Plastic DIP16 (0.25) MECHANICAL DATA

DIM. mm inch

MIN. TYP. MAX. MIN. TYP. MAX.

a1 0.51 0.020

B 0.77 1.65 0.030 0.065

b 0.5 0.020

b1 0.25 0.010

D 20 0.787

E 8.5 0.335

e 2.54 0.100

e3 17.78 0.700

F 7.1 0.280

I 5.1 0.201

L 3.3 0.130

Z 1.27 0.050

P001C

M54/M74HC148

7/11

8/12/2019 74hct148

8/11

Ceramic DIP16/1 MECHANICAL DATA

DIM. mm inchMIN. TYP. MAX. MIN. TYP. MAX.

A 20 0.787

B 7 0.276

D 3.3 0.130

E 0.38 0.015

e3 17.78 0.700

F 2.29 2.79 0.090 0.110

G 0.4 0.55 0.016 0.022H 1.17 1.52 0.046 0.060

L 0.22 0.31 0.009 0.012

M 0.51 1.27 0.020 0.050

N 10.3 0.406

P 7.8 8.05 0.307 0.317

Q 5.08 0.200

P053D

M54/M74HC148

8/11

8/12/2019 74hct148

9/11

SO16 (Narrow) MECHANICAL DATA

DIM. mm inchMIN. TYP. MAX. MIN. TYP. MAX.

A 1.75 0.068

a1 0.1 0.2 0.004 0.007

a2 1.65 0.064

b 0.35 0.46 0.013 0.018

b1 0.19 0.25 0.007 0.010

C 0.5 0.019

c1 45 (typ.)D 9.8 10 0.385 0.393

E 5.8 6.2 0.228 0.244e 1.27 0.050

e3 8.89 0.350

F 3.8 4.0 0.149 0.157

G 4.6 5.3 0.181 0.208

L 0.5 1.27 0.019 0.050

M 0.62 0.024

S 8 (max.)

P013H

M54/M74HC148

9/11

8/12/2019 74hct148

10/11

8/12/2019 74hct148

11/11

Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsability for theconsequences of use of such information nor for any infringement of patents or other rights of third parties which may results from its use. Nolicense is granted by implication or otherwiseunder any patentor patent rights of SGS-THOMSON Microelectronics. Specificationsmentionedin this publication are subject to change without notice. This publication supersedes and replaces all information previously supplied.SGS-THOMSON Microelectronicsproducts are not authorized foruse ascritical componentsin life support devices or systemswithout expresswritten approval of SGS-THOMSON Microelectonics.

1994 SGS-THOMSON Microelectronics - All Rights Reserved

SGS-THOMSON Microelectronics GROUP OF COMPANIESAustralia - Brazil - France - Germany - Hong Kong - Italy - Japan - Korea - Malaysia - Malta - Morocco - The Netherlands -

Singapore - Spain - Sweden - Switzerland - Taiwan - Thailand - United Kingdom - U.S.A

M54/M74HC148

11/11