ST 74LVC244A User Manual

74LVC244A

LOW VOLTAGE CMOS QUAD BUS BUFFERS (3-STATE)

HIGH PERFORMANCE

■ 5V TOLERANT INPUTS

■ HIGH SPEED: t

■ POWER DOWN PROTECTION ON INPUTS

= 5.9ns (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 244

■ LA TCH-UP PERFORMANCE EXCEEDS

500mA (JESD 17)

■ ESD PERFORMANCE:

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

DESCRIPTION

The 74LVC244A is a lo w voltage CMOS OCTAL
BUS BUFFER (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.

TSSOPSOP

Table 1: Order Codes

PACKAGE T & R

SOP 74LVC244AMTR

TSSOP 74LVC244ATTR

It can be interfaced to 5V signal environment for
inputs in mixed 3.3/5V system.
G

control output governs four BUS BUFFERs.
This device is designed to be used with 3 state
memory address drivers, etc.
It has more sp eed performance at 3.3V than 5V
AC/ACT family, combined with a lower power
consumption.
All inputs and outputs are equipped with
protection circuits against static disc harge, giving
them 2KV ESD immunity and transient excess
voltage.

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

.

Rev. 5

1/12July 2004

74LVC244A

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

11G

Output Enable Input
2, 4, 6, 8 1A1 to 1A4 Data Inputs
9, 7, 5, 3 2Y1 to 2Y4 Data Outputs

11, 13, 15, 172A1 to 2A4 Data Inputs

18, 16, 14, 121Y1 to 1Y4 Data Outputs

19 2G

Output Enable Input

X : Don’t care
Z : High Impedance

INPUTS OUTPUT

G

An Yn

LLL
LHH

HXZ

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

74LVC244A

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

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 or V

I

IL

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

± 5 ± 5 µA

VO = 0 to 5.5V

3.6

2.7 to 3.6

VI = VCC or GND

V

or VO = 3.6 to

I

5.5V

VIH = VCC-0.6V

10 10

± 10 ± 10

500 500 µA

Unit

V

CC

V

V

V

µA

3/12

74LVC244A

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 9.0 12

2.3 to 2.7 30 500 2.0 7.9 10.5

2.7 50 500 2.5 1.5 6.9 8.3

-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 5.9 7.1

t

PZL tPZH

Output Enable Time 1.65 to 1.95 30 1000 2.0 11 14.3

2.3 to 2.7 30 500 2.0 9.6 12.5

2.7 50 500 2.5 1 8.6 10.3

ns

3.0 to 3.6 50 500 2.5 1 7.6 9.1

t

PLZ tPHZ

Output Disable Time 1.65 to 1.95 30 1000 2.0 9.0 11.7

2.3 to 2.7 30 500 2.0 7.8 10.1

2.7 50 500 2.5 2 6.8 8.2

ns

3.0 to 3.6 50 500 2.5 2 6.5 7.8

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)

4/12