Datasheet M74HCT245 Datasheet (ST)

M74HCT245

OCTAL BUS TRANSCEIVER

WITH 3 STATE OUTPUTS (NON INVERTED)

■ HIGH SPEED:

t

= 13ns (TYP.) at VCC = 4.5V

PD

■ LOW POWER DISSIPATION:

I

= 4µA(MAX.) at TA=25°C

CC

■ COMPA TIBLE WITH TTL OUTPUTS :

V

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

IH

■ SYMMETRICAL OUTPUT IMPEDANCE:

|I

| = IOL = 6mA (MIN)

OH

■ BALANCED PROPAGATION DELAYS:

t

≅ t

PHL

PLH

■ PIN AND FUNCTION COMPATIBLE WITH

74 SERIES 245

DESCRIPTION

The M74HCT245 is an advanced high-speed CMOS OCTAL BUS TRANSCEIVER (3-STATE) fabricated with silicon gate C

2

MOS technology. This IC is intended for two-way asynchronous communication between data buses, and the direction of data transmission is determined by DIR input. The enable input G

can be used to disable the device so that the buses are effectively isolated.

TSSOPDIP SOP

ORDER CODES

PACKAGE TUBE T & R

DIP M74HCT245B1R

SOP M74HCT245M1R M74HCT245RM13TR

TSSOP M74HCT245TTR

All inputs are equipped with protection circuits against static discharge and transient excess voltage. All floating bus terminals during High Z State must be held HIGH or LOW.

PIN CONNECTION AND IEC LOGIC SYMBOLS

1/9August 2001

M74HCT245

INPUT AND OUTPUT EQUIVALENT CIRCUIT PIN DESCRIPTION

PIN No SYMBOL NAME AND FUNCTION

1 DIR Directional Control

2, 3, 4, 5, 6,

7, 8, 9

18, 17, 16, 15, 14, 13,

12, 11

19 G 10 GND Ground (0V) 20 V

TRUTH TABLE

INPUTS FUNCTION OUTPUT

A1 to A8 Data Inputs/Outputs

B1 to B8 Data Inputs/Outputs

CC

Output Enable Input

Positive Supply Voltage

G

DIR A BUS B BUS Yn

L L OUTPUT INPUT A = B L H INPUT OUTPUT B = A

HXZZZ

X : Don’t Care Z : High Impedance

ABSOLUTE MAXIMUM RATINGS

Symbol Parameter Value Unit

V

I

OK

I

or I

CC

P

T

Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is not implied (*) 500mW at 65

Supply Voltage

CC

DC Input Voltage -0.5 to VCC + 0.5

I

DC Output Voltage -0.5 to VCC + 0.5

O

DC Input Diode Current

IK

DC Output Diode Current DC Output Current

O

DC VCC or Ground Current

GND

Power Dissipation

D

Storage Temperature

stg

Lead Temperature (10 sec)

L

; derate to 30 0m W by 10mW/°C from 65

°C

°C to 85°C

-0.5 to +7 V V V

± 20 mA ± 20 mA ± 35 mA ± 70 mA

500(*) mW

-65 to +150 °C

300 °C

RECOMMENDED OPERATING CONDITIONS

Symbol Parameter Value Unit

2/9

V

V T t

r

Supply Voltage

CC

Input Voltage 0 to V

I

Output Voltage 0 to V

O

Operating Temperature

op

, t

Input Rise and Fall Time (VCC = 4.5 to 5.5V)

f

4.5 to 5.5 V

CC CC

-55 to 125 °C 0 to 500 ns

V V

DC SPECIFICATIONS

Symbol Parameter

V

I

∆ I

High Level Input

IH

Voltage

Low Level Input

IL

Voltage

High Level Output

OH

Voltage Low Level Output

OL

Voltage

I

Input Leakage

I

Current High Impedance

OZ

Output Leakage Current

Quiescent Supply

CC

Current Additional Worst

CC

Case Supply Current

Test Condition Value

T

= 25°C

V

(V)

CC

A

Min. Typ. Max. Min. Max. Min. Max.

4.5 to

2.0 2.0 2.0 V

5.5

4.5 to

0.8 0.8 0.8 V

5.5

4.5

5.5

IO=-20 µA

I

=-6.0 mA

O

IO=20 µA

I

=6.0 mA

O

= VCC or GND

V

I

= VIH or V

V

I

VO = VCC or GND

= VCC or GND

V

I

5.5 Per Input pin

= 0.5V or

V

I

V

= 2.4V

I

4.4 4.5 4.4 4.4

4.18 4.31 4.13 4.10

0.0 0.1 0.1 0.1

0.17 0.26 0.33 0.40 ± 0.1 ± 1 ± 1 µA

IL

± 0.5 ± 5 ± 10 µA

2.0 2.9 3.0 mA

Other Inputs at

V

or GND

CC

I

= 0

O

M74HCT245

-40 to 85°C -55 to 125°C

44080µA

Unit

V

AC ELECTRICAL CHARACTERISTICS (C

Test Condition Value

Symbol Parameter

t

TLH tTHL

t

PLH tPHL

t

PZL tPZH

Output Transition Time

Propagation Delay Time

High Impedance Output Enable Time

t

PLZ tPHZ

High Impedance Output Disable Time

C

V

CC

(V)

L

(pF)

4.5 50 7 12 15 18 ns 50 13 22 28 33

4.5

150 18 30 38 45

50

4.5

150

4.5 50

= 50 pF, Input tr = tf = 6ns)

L

= 25°C

T

A

Min. Typ. Max. Min. Max. Min. Max.

R

= 1 KΩ

L

R

= 1 KΩ

L

R

= 1 KΩ

L

19 30 38 45 24 38 48 57

17 30 38 45 ns

-40 to 85°C -55 to 125°C

Unit

ns

3/9

M74HCT245

CAPACITIVE CHARACTERISTICS

Test Condition Value

T

Symbol Parameter

C

I/OUT

C

Input Capacitance

IN

Output Capacitance

Power Dissipation

PD

Capacitance (note

V

(V)

CC

DIR, G An, Bn 13 pF

= 25°C

A

Min. Typ. Max. Min. Max. Min. Max.

5101010pF

41 pF

1)

1) CPD is defined as the value of the IC’s internal equivalent capacitance which is calculated from the operating current consumption without

load. (Refer to Test Circuit). Average operating current can be obtained by the following equation. I

TEST CIRCUIT

-40 to 85°C -55 to 125°C

= CPD x VCC x fIN + ICC/8 (per circuit)

CC(opr)

Unit

TEST SWITCH

t

, t

PLH

PHL

, t

t

PZL

PLZ

t

, t

PZH

PHZ

CL = 50pF/150p F or equivalen t (includes j i g and probe capacitance )

= 1KΩ or equivalent

R

1

= Z

R

of pulse generator (typically 50Ω)

T

OUT

4/9

Open

V

CC

GND

WAVEFORM 1 : PROPAGATION DELAY TIME (f=1MHz; 50% duty cycle)

M74HCT245

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

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M74HCT245

Plastic DIP-20 (0.25) MECHANICAL DATA

mm. inch

DIM.

MIN. TYP MAX. MIN. TYP. MAX.

a1 0.254 0.010

B 1.39 1.65 0.055 0.065 b 0.45 0.018

b1 0.25 0.010

D 25.4 1.000 E 8.5 0.335

e 2.54 0.100

e3 22.86 0.900

F 7.1 0.280

I 3.93 0.155

L 3.3 0.130

Z 1.34 0.053

6/9

P001J

SO-20 MECHANICAL DATA

M74HCT245

DIM.

MIN. TYP MAX. MIN. TYP. MAX.

A 2.65 0.104 a1 0.1 0.2 0.004 0.008 a2 2.45 0.096

b 0.35 0.49 0.014 0.019

b1 0.23 0.32 0.009 0.012

C 0.5 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 0.300

L 0.50 1.27 0.020 0.050

M 0.75 0.029

S8° (max.)

mm. inch

PO13L

7/9

M74HCT245

TSSOP20 MECHANICAL DATA

mm. inch

DIM.

MIN. TYP MAX. MIN. TYP. MAX.

A 1.2 0.047

A1 0.05 0.15 0.002 0.004 0.006

A2 0.8 1 1.05 0.031 0.039 0.041

b 0.19 0.30 0.007 0.012

c 0.09 0.20 0.004 0.0089

D 6.4 6.5 6.6 0.252 0.256 0.260

E 6.2 6.4 6.6 0.244 0.252 0.260

E1 4.3 4.4 4.48 0.169 0.173 0.176

e 0.65 BSC 0.0256 BSC

K0° 8°0° 8°

L 0.45 0.60 0.75 0.018 0.024 0.030

A2

A

A1

b

e

K

c

L

E

D

E1

PIN 1 IDENTIFICATION

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1

0087225C

M74HCT245

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