Datasheet 74VHCT240A Datasheet (SGS Thomson Microelectronics)



74VHCT240A

OCTAL BUS BUFFER

WITH 3 STATE OUTPUTS (INVERTED)

■ HIGHSPEED:t

■ LOW POWER DISSIPATION:

=4 µA (MAX.)at TA=25oC

I

CC

■ COMPATIBLEWITH TTLOUTPUTS:

=2V(MIN),VIL=0.8V(MAX)

V

IH

■ POWERDOWNPROTECTIONON INPUTS&

=5ns (TYP.)atVCC=5V

PD

OUTPUTS

■ SYMMETRICALOUTPUT IMPEDANCE:

|I

|=IOL=8 mA(MIN)

OH

■ BALANCEDPROPAGATIONDELAYS:

t

≅ t

PLH

PHL

■ OPERATINGVOLTAGERANGE:

(OPR)= 4.5Vto 5.5V

V

CC

■ PINANDFUNCTION COMPATIBLEWITH

74SERIES 240

■ IMPROVEDLATCH-UP IMMUNITY

■ LOWNOISE:V

= 0.9V(Max.)

OLP

DESCRIPTION

The 74VHCT240A is an advanced high-speed
CMOS OCTAL BUS BUFFER (3-STATE)
fabricated with sub-micron silicon gate and
double-layermetal wiringC

2

MOS technology.

M

(Micro Package)

(TSSOPPackage)

T

ORDERCODES :

74VHCT240AM 74VHCT240AT

G output enablegoverns four BUS BUFFERs.
This device is designed to be used with 3 state

memoryaddress drivers, etc.
Power down protection is provided on all inputs
and outputs and 0 to 7V can be accepted on
inputs with no regard to the supply voltage. This
devicecan be used to interface5V to 3V.

All inputs and outputs are equipped with
protection circuits against static discharge, giving
them 2KV ESD immunity and transient excess
voltage.

PIN CONNECTION AND IEC LOGIC SYMBOLS

August 1999

1/8

74VHCT240A

INPUT EQUIVALENTCIRCUIT

TRUTH TABLE

INPUT OUTPU T

GAnYn

LLH
LHL

HXZ

X:”H” or”L”
Z:Highimpedance

ABSOLUTE MAXIMUM RATINGS

PIN DESCRIPTION

PI N No SYM BO L NAM E AN D F UNCT I ON

1 1G Output Enable Input
2,4,6,8 1A1to1A4 Data Inputs
9,7,5,3 2Y1to2Y4 Data Outputs

11,13,15,17 2A1to2A4 Data Inputs
18,16,14,12 1Y1to1Y4 Data Outputs

19 2G Output Enable Input
10 GND Ground (0V)
20 V

Positive Supply Voltage

CC

Symb o l Para met er Value U n i t

V

V
V
V

I

I

OK

I

orI

I

CC

T

T

AbsoluteMaximum Ratingsarethosevaluesbeyond whichdamagetothedevicemayoccur. Functional operationunderthese condition isnotimplied.

1)Outputin OFFState

2)HighorLowState

Supply Voltage -0.5to+7.0 V

CC

DC Input Voltage -0.5to+7.0 V

I

DC Output Voltage (see note 1) -0.5to+7.0 V

O

DC Output Voltage (see note 2) -0.5toVCC+0.5 V

O

DC Input Diode Current -20 mA

IK

DC Output Diode Current
DC Output Current ±25 mA

O

DC VCCor Ground Current ±50 mA

GND

Storage Temperature -65to+150

stg

Lead Temperature (10 sec) 300

L

20 mA

±

o

C

o

C

RECOMMENDEDOPERATINGCONDITIONS

Symb o l Para met er Value Unit

V

V
V
V

T

dt/dv

1)Outputin OFFState

2)HighorLowState

3)V

from0.8Vto 2V

IN

2/8

Supply Voltage 4.5to5.5 V

CC

Input Voltage 0to5.5 V

I

Output Voltage (see note 1) 0to5.5 V

O

Output Voltage (see note 2) 0toV

O

Operating Temperature -40to+85

op

Input Rise and Fall Time (see note 3) (V

=5.0±0.5V)

CC

CC

0to20 ns/V

V

o

C

74VHCT240A

DC SPECIFICATIONS

Symb o l Para met er Test Con dit io ns Val u e Un i t

T

V

CC

High Level Input

V

IH

(V)

4.5to5.5 2 2 V

Min. Typ. Max. Min. Max.

Voltage
Low Level Input

V

IL

4.5to5.5 0.8 0.8 V

Voltage
High Level Output

V

OH

Voltage
Low Level Output

V

OL

Voltage
High Impedance

I

OZ

Output Leakage

4.5 IO=-50µA4.44.5 4.4

4.5 I

=-8mA 3.94 3.8

O

4.5 IO=50µA 0.0 0.1 0.1

4.5 I

4.5to5.5 VI=VIHorV

=8mA 0.36 0.44

O

IL

VO=0Vto5.5V

Current
Input Leakage Current 0to5.5 VI=5.5Vor GND ±0.1 ±1.0 µA

I

I

Quiescent Supply

I

CC

5.5 VI=VCCorGND 2 20

Current
Additional Worst Case

∆I

CC

Supply Current

5.5 One Inputat 3.4V,
other input at V

CC

or

GND

I

Output Leakage

OPD

0V

=5.5V 0.5 5.0

OUT

Current

=25oC -40 t o 85oC

A

±0.25 ±2.5 µA

1.35 1.5 mA

µ

µ

V

V

A

A

AC ELECTRICAL CHARACTERISTICS (Input tr=tf=3 ns)

Symbol Parameter Test Co ndition Value Unit

t

Propagation Delay

PLH

t

Time

PHL

Output Disable Time 5.0

t

PLZ

t

PHZ

t

Output Enable Time 5.0

PZL

t

PZH

(*) Voltagerangeis5.0V± 0.5V

V

(V)

5.0

5.0

5.0

CC

C

L

(pF)

(*)
(*)

(*)
(*)
(*)

15 5.6 7.8 1.0 9.0
50 6.1 8.8 1.0 10.0
15 RL=1K
50 8.2 11.4 1.0 13.0
50 RL=1K

Min. Typ. Max. Min. Max.

Ω

Ω

=25oC -40 t o 85oC

T

A

7.7 10.4 1.0 12.0

8.8 11.4 1.0 13.0

ns

ns

ns

3/8

74VHCT240A

CAPACITIVE CHARACTERISTICS

Symb o l Para met er Test Con dit io ns Val u e Un i t

=25oC -40 t o 85oC

T

A

Min. Typ. Max. Min. Max.

Input Capacitance 4 10 10

C

IN

C

Output Capacitance 9

OUT

Power Dissipation

C

PD

19 pF

Capacitance (note 1)

1)CPDisdefinedasthevalueoftheIC’sinternalequivalent capacitance whichis calculated fromtheoperatingcurrentconsumption withoutload.(Referto
TestCircuit).Average operatingcurrent canbeobtainedbythefollowingequation.I

(opr)=CPD• VCC• fIN+ICC/8(per Circuit)

CC

DYNAMICSWITCHING CHARACTERISTICS

Symb o l Para met er Test Con dit io ns Val u e Un i t

T

V

CC

(V)

V
V

Dynamic Low Voltage

OLP

Quiet Output (note 1, 2)

OLV

Dynamic High Voltage

V

IHD

5.0

5.0 2.0

=50pF

C

L

Min. Typ. Max. Min. Max.

Input (note 1, 3)
Dynamic Low Voltage

V

ILD

5.0 0.8

Input (note 1, 3)

1)Worstcasepackage.

2)Maxnumber ofoutputsdefined as(n).Datainputs aredriven0Vto 5.0V,(n-1)outputs switching andoneoutput atGND.

3)Maxnumber ofdatainputs(n)switching.(n-1)switching0Vto5.0V. Inputsunder testswitching: 5.0Vtothreshold (V

=25oC -40 t o 85oC

A

0.9 1.1

-1.1 -0.9

),0Vtothreshold (V

ILD

),f=1MHz.

IHD

pF
pF

V

TESTCIRCUIT

TEST SWITCH

t

PLH,tPHL

t

PZL,tPLZ

t

PZH,tPHZ

CL= 15/50 pF or equivalent (includes jig and probe capacitance)

=1KΩorequivalent

R

L=R1

R

ofpulse generator (typically50Ω)

T=ZOUT

Open

V

CC

GND

4/8

74VHCT240A

WAVEFORM 1: PROPAGATIONDELAYS

(f=1MHz;50% duty cycle)

WAVEFORM 2: OUTPUT ENABLE AND DISABLE TIME (f=1MHz; 50%duty cycle)

5/8

74VHCT240A

SO-20 MECHANICAL DATA

DIM.

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

A 2.65 0.104
a1 0.10 0.20 0.004 0.007
a2 2.45 0.096

b 0.35 0.49 0.013 0.019
b1 0.23 0.32 0.009 0.012

C 0.50 0.020

c1 45 (typ.)

D 12.60 13.00 0.496 0.512

E 10.00 10.65 0.393 0.419

e 1.27 0.050
e3 11.43 0.450

F 7.40 7.60 0.291 0.299

L 0.50 1.27 0.19 0.050

M 0.75 0.029

S 8 (max.)

mm inch

6/8

P013L

TSSOP20 MECHANICAL DATA

74VHCT240A

DIM.

mm inch

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

A 1.1 0.433

A1 0.05 0.10 0.15 0.002 0.004 0.006

A2 0.85 0.9 0.95 0.335 0.354 0.374

b 0.19 0.30 0.0075 0.0118

c 0.09 0.2 0.0035 0.0079

D 6.4 6.5 6.6 0.252 0.256 0.260

E 6.25 6.4 6.5 0.246 0.252 0.256

E1 4.3 4.4 4.48 0.169 0.173 0.176

e 0.65 BSC 0.0256 BSC

K0

o

o

4

o

8

o

0

o

4

L 0.50 0.60 0.70 0.020 0.024 0.028

o

8

A2

A

A1

PIN 1 IDENTIFICATION

b

e

K

c

L

E

D

E1

1

7/8

74VHCT240A

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subject tochange without notice. Thispublication supersedes and replaces all information previously supplied. STMicroelectronics products
are not authorized for use as critical components in life support devices or systems without express written approval of STMicroelectronics.

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