Datasheet 74VHCT245A Datasheet (ST)

74VHCT245A

OCTAL BUS

TRANSCEIVER (3-STATE)

■ HIGH SPEED: t

■ LOW POWER DISSIPATION:

I

= 4 µA (MAX.) at TA=25°C

CC

■ COMPATIBLE WITH TTL OUTP U TS:

V

= 2V (M IN.), V

IH

■ POWER DOWN PROTECTION ON INPUTS

= 4.5 ns (TYP.) at VCC = 5V

PD

= 0.8V (MAX)

IL

& OUTPUTS

■ SYMMETRICAL OUTPUT IMPEDANCE:

|I

| = IOL = 8 mA (MIN)

OH

■ BALANCED PROPAGATION DELAYS:

t

≅ t

PLH

PHL

■ OPERATING VOLTAGE RANGE:

V

(OPR) = 4.5V to 5.5V

CC

■ PIN AND FUNCTION COMPATIBLE WITH

74 SERIES 245

■ IMPROVED LATCH-UP IMMUNITY

■ LOW NOISE: V

= 0.9V (MAX.)

OLP

DESCRIPTION

The 74VHCT245A is an advanced high-speed CMOS OCTAL BUS TRANSCEIVER (3-STATE) fabricated with sub-micron silicon gate and double-layer metal wiring C

2

MOS technology. This IC is intended for two-way asynchronous communication between data busses; the

TSSOPSOP

Table 1: Order Codes

PACKAGE T & R

SOP 74VHCT245AMTR

TSSOP 74VHCT245ATTR

direction of data transmission is determined by DIR input. The enable input G

can be used to disable the device so that the busses are effectivel y isolated. All inputs and outputs are equipped with protection circuits against static disc harge, 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 Connection And IEC Logic Symbols

Rev. 4

1/13December 2004

74VHCT245A

Figure 2: Input/ Output Equivalent Circuit

Figure 3: Input Equivalent Circuit Table 2: Pin Description

PIN N° 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

A1 to A8 Data Inputs/Outputs

B1 to B8 Data Inputs/Outputs

Enable Input

CC

Positive Supply Voltage

Table 3: Truth Table

INPUTS FUNCTION

G

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

HXZZZ

X : Don‘t Ca re Z : High Impedance

2/13

DIR A BUS B BUS

OUTPUT

74VHCT245A

Table 4: Absolute Maximum Ratings

Symbol Parameter Value Unit

V

V V V

I

OK

I

or I

I

CC

T

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

1) Output in OFF State

2) High or Low State. I

Table 5: Recommended Operating Conditions

Symbol Parameter Value Unit

V

V V V

T

dt/dv

Supply Voltage

CC

DC Input Voltage (DIR, G)

I

DC BUS I/O Voltage (see note 1)

I/O

DC BUS I/O Voltage (see note 2) -0.5 to VCC + 0.5

I/O

DC Input Diode Current

IK

DC Output Diode Current DC Output Current

O

DC VCC or Ground Current

GND

Storage Temperature

stg

Lead Temperature (10 sec)

L

absolute maximum rating must be observed

O

Supply Voltage

CC

Input Voltage

I

BUS I/O Voltage (see note 1)

I/O

BUS I/O Voltage (see note 2) 0 to V

I/O

Operating Temperature

op

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

= 5.0 ± 0.5V)

CC

-0.5 to +7.0 V

- 20 mA

± 20 mA ± 25 mA ± 75 mA

-65 to +150 °C 300 °C

4.5 to 5.5 V 0 to 5.5 V 0 to 5.5 V

CC

-55 to 125 °C 0 to 20 ns/V

V

1) Output in OFF State

2) High or Low State. I

3) V

from 0.8V to 2V

IN

absolute maximum rating must be observed

O

3/13

74VHCT245A

Table 6: DC Specifications

Symbol Parameter

V

+I

I

High Level Input

IH

Voltage Low Level Input

V

IL

Voltage High Level Output

OH

Voltage Low Level Output

OL

Voltage

I

High Impedance

OZ

Output Leakage Current

Input Leakage

I

Current Quiescent Supply

I

CC

Current Additional Worst

CC

Case Supply Current

Output Leakage

OPD

Current

4.5 to

Test Condition Value

= 25°C

T

V

CC

(V)

5.5

4.5

5.5

0 to

5.5

=-50 µA

I

O

=-8 mA

I

O

=50 µA

I

O

=8 mA

I

O

= VIH or V

V

I

VO = 0V to 5.5V

= 5.5V or GND

V

I

= VCC or GND

V

I

IL

A

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

222V

0.8 0.8 0.8 V

4.4 4.5 4.4 4.4

3.94 3.8 3.7

0.0 0.1 0.1 0.1

0.36 0.44 0.55

±0.25 ± 2.5 ± 2.5 µA

± 0.1 ± 1.0 ± 1.0 µA

One Input at 3.4V,

5.5

other input at V

CC

1.35 1.5 1.5 mA

or GND

= 5.5V

0

V

OUT

0.5 5.0 5.0 µA

-40 to 85°C -55 to 125°C

Unit

V

44040µA

Table 7: AC Electrical Characteristics (Input t

Test Condition Value

Symbol Parameter

t

Propagation Delay

PLH

t t

t

OSLH

t

OSHL

(*) Voltage range is 5.0V ± 0.5V Note 1: Parameter guaranteed by design. t

Time

PHL

Output Enable

PZL

Time

PZH

Output Disable

PLZ

Time

PHZ

Output to Output Skew Time (note 1)

(*)

(V)

C

(pF)

L

V

CC

5.0 15 4.5 7.5 1.0 8.5 1.0 10.0

5.0 50 5.3 8.7 1.0 9.5 1.0 11.0

5.0 15

5.0 50 9.7 14.8 1.0 16.0 1.0 17.0

RL = 1KΩ

5.0 50 RL = 1K

5.0 50 1.0 1.0 1.0 ns

= |t

pLHm

- t

pLHn

soLH

= tf = 3ns)

r

= 25°C

T

A

-40 to 85°C -55 to 125°C

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

9.0 13.8 1.0 15.0 1.0 16.0

Ω 10.0 15.4 1.0 16.5 1.0 17.5 ns

|, t

= |t

- t

soHL

pHLm

pHLn

|

Unit

ns

4/13

Table 8: Capacitive Characteristics

Test Condition Value

Symbol Parameter

C C C

Input Capacitance

IN

Bus Input

I/O

Capacitance Power Dissipation

PD

Capacitance (note 1)

74VHCT245A

= 25°C

T

A

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

610 10 10pF 8pF

18 pF

-40 to 85°C -55 to 125°C

Unit

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/8 (per c ircuit )

CC(opr)

Table 4: DYNAMIC SWITCHING CHARACTERISTICS

Test Condition Value

= 25°C

Symbol Parameter

V V

Dynamic Low

OLP

Voltage Quiet

OLV

Output (note 1, 2)

V

(V)

5.0

CC

T

A

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

0.6 0.9

-0.9 -0.6

Dynamic High

V

IHD

Voltage Input

5.0 2.0

= 50 pF

C

L

(note 1, 3) Dynamic Low

V

ILD

Voltage Input

5.0 0.8

(note 1, 3)

1) Worst case package.

2) Max number of outp ut s defined as (n). Data inpu t s are driven 0V to 3.0V, (n-1) outputs switc hi ng and one output at GND.

3) Max number of data inputs (n) switching. (n-1) switching 0V to 3.0V. Inputs under test switching: 3.0V to threshold (V ), f=1MHz.

(V

IHD

-40 to 85°C -55 to 125°C

), 0V to thresho l d

ILD

Unit

V

5/13

74VHCT245A

Figure 5: Test Circuit

t

, t

PLH

PHL

, t

t

PZL

PLZ

t

, t

PZH

PHZ

TEST SWITCH

Open

V

CC

GND

CL =15/ 50pF or e qui valent (includes jig an d probe capacit ance)

= R1 = 1KΩ or equivalent

R

L

R

= Z

of pulse generator (typically 50Ω)

T

OUT

Figure 6: Waveform - Propagation Delays (f=1MHz; 50% duty cycle)

6/13

74VHCT245A

Figure 7: Waveform - Output Enable And Disable Time (f=1MHz; 50% duty cycle)

7/13

74VHCT245A

SO-20 MECHANICAL DATA

DIM.

A 2.35 2.65 0.093 0.104

A1 0.1 0.30 0.004 0.012

B 0.33 0.51 0.013 0.020 C 0.23 0.32 0.009 0.013 D 12.60 13.00 0.496 0.512 E 7.4 7.6 0.291 0.299 e 1.27 0.050 H 10.00 10.65 0.394 0.419 h 0.25 0.75 0.010 0.030 L 0.4 1.27 0.016 0.050 k0° 8° 0° 8°

ddd 0.100 0.004

MIN. TYP MAX. MIN. TYP. MAX.

mm. inch

8/13

0016022D

74VHCT245A

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 0.0079

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

1

0087225C

9/13

74VHCT245A

Tape & Reel SO-20 MECHANICAL

mm. inch

DIM.

MIN. TYP MAX. MIN. TYP. MAX.

A 330 12.992 C 12.8 13.2 0.504 0.519 D 20.2 0.795 N 60 2.362

T 30.4 1.197 Ao 10.8 11 0.425 0.433 Bo 13.2 13.4 0.520 0.528 Ko 3.1 3.3 0.122 0.130 Po 3.9 4.1 0.153 0.161

P 11.9 12.1 0.468 0.476

DATA

10/13

74VHCT245A

Tape & Reel TSSOP20 MECHANICAL DATA

mm. inch

DIM.

MIN. TYP MAX. MIN. TYP. MAX.

A 330 12.992

C 12.8 13.2 0.504 0.519

D 20.2 0.795

N 60 2.362

T 22.4 0.882 Ao 6.8 7 0.268 0.276 Bo 6.9 7.1 0.272 0.280 Ko 1.7 1.9 0.067 0.075 Po 3.9 4.1 0.153 0.161

P 11.9 12.1 0.468 0.476

11/13

74VHCT245A

Table 9: Revision History

Date Revision Description of Change s

16-Dec-2004 4 Order Codes Revision - pag. 1.

12/13

74VHCT245A

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