ST M74HC245 User Manual

M74HC245

OCTAL BUS TRANSCEIVER

WITH 3 STATE OUTPUTS (NON INVERTED)

■ HIGH SPEED:

t

= 10ns (TYP.) at VCC = 6V

PD

■ LOW POWER DISSIPATION:

I

= 4µA(MAX.) at TA=25°C

CC

■ HIGH NOISE IMMUNITY:

V

= V

NIH

■ SYMMETRICAL OUTPUT IMPEDANCE:

|I

| = IOL = 6mA (MIN)

OH

■ BALANCED PROPAGATION DELAYS:

≅ t

t

PLH

■ WIDE OPERATING VOLTAGE RANGE:

V

(OPR) = 2V to 6V

CC

■ PIN AND FUNCTION COMPATIBLE WITH

= 28 % VCC (MIN.)

NIL

PHL

74 SERIES 245

DESCRIPTION

The M74HC245 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

TSSOPDIP SOP

ORDER CODES

PACKAGE TUBE T & R

DIP M74HC245B1R

SOP M74HC245M1R M74HC245RM13TR

TSSOP M74HC245TTR

disable the device so that the buses are effectively isolated. 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

1/10July 2001

M74HC245

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

2/10

V

T

t

r

Supply Voltage

CC

Input Voltage 0 to V

I

Output Voltage 0 to V

O

Operating Temperature

op

Input Rise and Fall Time VCC = 2.0V

, t

f

V V

CC CC

= 4.5V = 6.0V

2 to 6 V

CC CC

-55 to 125 °C 0 to 1000 ns

0 to 500 ns 0 to 400 ns

V V

DC SPECIFICATIONS

Symbol Parameter

V

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

M74HC245

Test Condition Value

T

= 25°C

V

(V)

CC

A

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

2.0 1.5 1.5 1.5

6.0 4.2 4.2 4.2

2.0 0.5 0.5 0.5

6.0 1.8 1.8 1.8

2.0

4.5

6.0

4.5

6.0

2.0

4.5

6.0

4.5

6.0

IO=-20 µA I

=-20 µA

O

I

=-20 µA

O

I

=-6.0 mA

O

I

=-7.8 mA

O

IO=20 µA I

=20 µA

O

I

=20 µA

O

I

=6.0 mA

O

I

=7.8 mA

O

= VCC or GND

V

I

= VIH or V

V

I

IL

VO = VCC or GND

= VCC or GND

V

I

1.9 2.0 1.9 1.9

4.4 4.5 4.4 4.4

5.9 6.0 5.9 5.9

4.18 4.31 4.13 4.10

5.68 5.8 5.63 5.60

0.0 0.1 0.1 0.1

0.17 0.26 0.33 0.40

0.18 0.26 0.33 0.40

-40 to 85°C -55 to 125°C

± 0.1 ± 1 ± 1 µA

± 0.5 ± 5 ± 10 µA

44080µA

Unit

V4.5 3.15 3.15 3.15

V4.5 1.35 1.35 1.35

V

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