ST 74LVC245A User Manual

74LVC245A

LOW VOLTAGE CMOS OCTAL BUS TRANSCEIVER

(NOT INVERTED) HIGH PERFORMANCE

■ 5V TOLERANT INPUTS

■ HIGH SPEED: t

■ POWER DOWN PROTECTION ON INPUTS

= 6.3ns (MAX.) at VCC = 3V

PD

AND OUTPUTS

■ SYMMETRICAL OUTPUT IMPEDANCE:

|I

| = IOL = 24mA (MIN) at VCC = 3V

OH

■ PCI BUS LEVELS GUARANTEED AT 24 mA

■ BALANCED PROPAGATION DELAYS:

t

≅ t

PLH

■ OPERATING VOLTAGE RANGE:

V

CC

PHL

(OPR) = 1.65V to 3.6V (1.2V Data

Retention)

■ PIN AND FUNCTION COMPATIBLE WITH

74 SERIES 245

■ LA TCH-UP PERFORMANCE EXCEEDS

500mA (JESD 17)

■ ESD PERFORMANCE:

HBM > 2000V (MIL STD 883 method 3015);
MM > 200V

DESCRIPTION

The 74LVC245A is a lo w voltage CMOS OCTAL
BUS TRANSCEIVER (3-STATE) fabricated with
sub-micron silicon gate and double-layer metal
wiring C
V

2

MOS technology. It is ideal for 1.65 to 3.6

operations and low power and low noise

CC

applications.
This IC is intended for two-way asynchronous
communication between data buses and the

TSSOPSOP

Table 1: Order Codes

PACKAGE T & R

SOP 74LVC245AMTR

TSSOP 74LVC245ATTR

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.
It has more sp eed performance at 3.3V than 5V
AC/ACT family, combined with a lower power
consumption.
All inputs are equipped with protection circuits
against static discharge, giving them 2KV ESD
immunity and transient excess voltage.
All floating bus terminals during High Z State must
be held HIGH or LOW.

Figure 1: Pin C onnection And I EC Logic Symbol s

.

Rev. 4

1/12July 2004

74LVC245A

Figure 2: Input An d Output Equival e n t Ci rcui t

Table 2: Pin Description Table 3: Truth Table

PIN N° SYMBOL NAME AND FUNCTION

1 DIR Directional Control

2, 3, 4, 5, 6,

A1 to A8 Data Inputs/Outputs

7, 8, 9

18, 17, 16,

B1 to B8 Data Inputs/Outputs

15, 14, 13,

12, 11

19 G

Output Enable Input

INPUTS FUNCTION OUTPUT

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

10 GND Ground (0V)
20 V

CC

Positive Supply Voltage

Table 4: Absolute Maximum Ratings

Symbol Parameter Value Unit

V

V
V
V

I

I

OK

I

or I

I

CC

T

T

Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is
not implied

1) IO absolute maximum rating must be observed
< GND

2) V

O

Supply Voltage

CC

DC Input Voltage

I

DC Output Voltage (High Impedance or VCC = 0V)

O

DC Output Voltage (High or Low State) (note 1) -0.5 to VCC + 0.5

O

DC Input Diode Current

IK

DC Output Diode Current (note 2)
DC Output Current

O

DC VCC or Ground Current per Supply Pin

GND

Storage Temperature

stg

Lead Temperature (10 sec)

L

-0.5 to +7.0 V

-0.5 to +7.0 V

-0.5 to +7.0 V
V

- 50 mA

- 50 mA

± 50 mA

± 100 mA

-65 to +150 °C

300 °C

2/12

74LVC245A

Table 5: Recommended Operating Conditions

Symbol Parameter Value Unit

V

V
V
V

I

OH

I

OH

I

OH

I

OH

T

dt/dv Input Rise and Fall Time (note 2) 0 to 10 ns/V

1) Truth T abl e guarante ed: 1.2V to 3.6V

2) VIN from 0.8V to 2V at VCC = 3.0V

Table 6: DC Specifications

Supply Voltage (note 1)

CC

Input Voltage

I

Output Voltage (High Impedance or VCC = 0V)

O

Output Voltage (High or Low State) 0 to V

O

, I

High or Low Level Output Current (VCC = 3.0 to 3.6V)

OL

, I

High or Low Level Output Current (VCC = 2.7 to 3.0V)

OL

, I

High or Low Level Output Current (VCC = 2.3 to 2.7V)

OL

, I

High or Low Level Output Current (VCC = 1.65 to 2.3V)

OL

Operating Temperature

op

Test Condition Value

1.65 to 3.6 V
0 to 5.5 V
0 to 5.5 V

CC

± 24 mA
± 12 mA

± 8mA
± 4mA

-55 to 125 °C

V

Symbol Parameter

High Level Input

V

IH

Voltage

V

Low Level Input

IL

Voltage

V

High Level Output

OH

Voltage

Low Level Output

V

OL

Voltage

Input Leakage Current

I

I

I

Power Off Leakage

off

Current

I

High Impedance

OZ

Output Leakage
Current

Quiescent Supply

I

CC

Current

∆I

CCICC

incr. per Input

V

CC

(V)

1.65 to 1.95

-40 to 85 °C -55 to 125 °C

Min. Max. Min. Max.

0.65V

CC

0.65V

CC

2.3 to 2.7 1.7 1.7

2.7 to 3.6 2 2

1.65 to 1.95

0.35V

CC

0.35V

2.3 to 2.7 0.7 0.7

2.7 to 3.6 0.8 0.8

1.65 to 3.6

1.65

2.3

2.7

3.0

3.0

1.65 to 3.6

1.65

2.3

2.7

3.0

3.6
0

3.6 V

3.6

2.7 to 3.6

IO=-100 µAVCC-0.2 VCC-0.2

=-4 mA

I

O

=-8 mA

I

O

=-12 mA

I

O

=-18 mA

I

O

I

=-24 mA

O

IO=100 µA

=4 mA

I

O

=8 mA

I

O

I

=12 mA

O

=24 mA

I

O

VI = 0 to 5.5V

or VO = 5.5V

V

I

= VIH orVIL

I

V

= 0 to 5.5V

O

VI = VCC or GND

V

or VO = 3.6 to

I

5.5V

VIH = VCC-0.6V

1.2 1.2

1.7 1.7

2.2 2.2

2.4 2.4

2.2 2.2

0.2 0.2

0.45 0.45

0.7 0.7

0.4 0.4

0.55 0.55
± 5 ± 5 µA

10 10 µA

± 10 ± 10 µA

10 10

± 10 ± 10

500 500 µA

Unit

V

CC

V

V

V

µA

3/12

74LVC245A

Table 7: Dynamic Switching Characteristics

Test Condition Value

= 25 °C

Symbol Parameter

V

CC

(V)

V

OLP

V

OLV

1) Number of output de fined as "n". M easured with "n -1" outputs switching fr om HI GH to LOW or LOW to HIGH. The rem ai ning output is
measur ed i n the LOW state.

Dynamic Low Level Quiet
Output (note 1)

3.3

= 50pF

C

L

V

= 0V, VIH = 3.3V

IL

Table 8: AC Electrical Characteristics

Test Condition Value

T

A

Min. Typ. Max.

0.8

-0.8

Unit

V

Symbol Parameter

t

PLH tPHL

Propagation Delay
Time

V

(V)

CC

C

(pF)

R

(Ω)

t

L

s

(ns)

L

1.65 to 1.95 30 1000 2.0 2.0 9.0 2.0 12

2.3 to 2.7 30 500 2.0 2.0 8.0 2.0 10.5

2.7 50 500 2.5 1.5 7.3 1.5 8.8

-40 to 85 °C -55 to 125 °C

= t

r

Min. Max. Min. Max.

Unit

ns

3.0 to 3.6 50 500 2.5 1.0 6.3 1.0 7.6

t

PZL tPZH

Output Enable Time 1.65 to 1.95 30 1000 2.0 2.0 12 2.0 16

2.3 to 2.7 30 500 2.0 2.0 9.5 2.0 12.5

2.7 50 500 2.5 1.0 9.0 1.0 11

ns

3.0 to 3.6 50 500 2.5 1.0 8.5 1.0 10

t

PLZ tPHZ

Output Disable Time 1.65 to 1.95 30 1000 2.0 2.0 11 2.0 14

2.3 to 2.7 30 500 2.0 2.0 9.0 2.0 12

2.7 50 500 2.5 2.0 8.5 2.0 10

ns

3.0 to 3.6 50 500 2.5 2.0 7.5 2.0 9.0

t

OSLH

t

OSHL

1) Skew is defined as the absolute value of the difference between the actual propagation delay for any two outputs of the same device switch­ing in the sa me directio n, either HIGH or LOW (t

2) Param eter guaran teed by design

Output To Output
Skew Time (note1,

2)

2.7 to 3.6 1 1 ns

OSLH

= | t

PLHm

- t

PLHn

|, t

OSHL

= | t

PHLm

- t

PHLn

|

Table 9: Capacitive Characteristics

Test Condition Value

= 25 °C

Symbol Parameter

C

C

Input Capacitance

IN

Power Dissipation Capacitance

PD

(note 1)

V

CC

(V)

1.8 fIN = 10MHz 28

T

A

Min. Typ. Max.

4pF

Unit

pF2.5 30

3.3 34

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

= CPD x VCC x fIN + ICC/n (per c ircuit )

CC(opr)

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