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 SN54BCT244, SN74BCT244

 OCTAL BUFFERS/DRIVERS

 WITH 3-STATE OUTPUTS

 SCBS006E – OCTOBER 1987 – REVISED APRIL 1994

Copyright 

©

 1994, Texas Instruments Incorporated

2–1

POST OFFICE BOX 655303 

 DALLAS, TEXAS 75265

State-of-the-Art BiCMOS Design

Significantly Reduces I

CCZ

P-N-P Inputs Reduce DC Loading

ESD Protection Exceeds 2000 V

Per MIL-STD-883C, Method 3015

3-State Outputs Drive Bus Lines or Buffer

Memory Address Registers

Package Options Include Plastic

Small-Outline (DW) and Shrink

Small-Outline (DB) Packages, Ceramic Chip

Carriers (FK) and Flatpacks (W), and

Standard Plastic and Ceramic 300-mil DIPs

(J, N)

   

description

These octal buffers and line drivers are designed

specifically to improve both the performance and

density of 3-state memory address drivers, clock

drivers, and bus-oriented receivers and

transmitters. Taken together with the 

BCT240

and 

BCT241, these devices provide the choice of

selected combinations of inverting and

noninverting outputs, symmetrical OE (active-low

output-enable) inputs, and complementary OE

and OE inputs.

The 

BCT244 is organized as two 4-bit buffers/line

drivers with separate output-enable (OE) inputs.

When OE is low, the device passes data from the

A inputs to the Y outputs. When OE is high, the

outputs are in the high-impedance state.

The SN54BCT244 is characterized for operation

over the full military temperature range of – 55

°

C

to 125

°

C. The SN74BCT244 is characterized for

operation from 0

°

C to 70

°

C.

FUNCTION TABLE

(each buffer)

INPUTS

OUTPUT

OE

A

Y

L

H

H

L

L

L

H

X

Z

1

2

3

4

5

6

7

8

9

10

20

19

18

17

16

15

14

13

12

11

1OE

1A1

2Y4

1A2

2Y3

1A3

2Y2

1A4

2Y1

GND

V

CC

2OE

1Y1

2A4

1Y2

2A3

1Y3

2A2

1Y4

2A1

SN54BCT244 . . . J  OR  W  PACKAGE

SN74BCT244 . . . DB OR DW OR N PACKAGE

(TOP VIEW)

3

2

1 20 19

9 10 11 12 13

4

5

6

7

8

18

17

16

15

14

1Y1

2A4

1Y2

2A3

1Y3

1A2

2Y3

1A3

2Y2

1A4

 SN54BCT244 . . . FK PACKAGE

(TOP VIEW)

2Y4

1A1

1OE

1Y4

2A2

2OE

2Y1

GND

2A1

V

CC

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.

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SN54BCT244, SN74BCT244

OCTAL BUFFERS/DRIVERS

WITH 3-STATE OUTPUTS

SCBS006E – OCTOBER 1987 – REVISED APRIL 1994

2–2

POST OFFICE BOX 655303 

 DALLAS, TEXAS 75265

logic symbol

logic diagram (positive logic)

1

2

4

6

8

19

11

13

15

17

3

5

7

9

12

14

16

18

1A1

1A2

1A3

1A4

1Y1

2A1

2A2

2A3

2A4

2Y1

1Y2

1Y3

1Y4

2Y2

2Y3

2Y4

2OE

1OE

2

1A1

4

1A2

6

1A3

8

1A4

EN

1

1Y1

18

1Y2

16

1Y3

14

1Y4

12

11

2A1

13

2A2

15

2A3

17

2A4

EN

19

2Y1

9

2Y2

7

2Y3

5

2Y4

3

1OE

2OE

† This symbol is in accordance with ANSI/IEEE Std 91-1984

and IEC Publication 617-12.

absolute maximum ratings over operating free-air temperature range (unless otherwise noted)

Supply voltage range, V

CC

– 0.5 V to 7 V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Input voltage range, V

I

 (see Note 1)

– 0.5 V to 7 V

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Voltage range applied to any output in the disabled or power-off state, V

O

– 0.5 V to 5.5 V

. . . . . . . . . . . . . . . 

Voltage range applied to any output in the high state, V

O

 

– 0.5 V to V

CC

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Current into any output in the low state: SN54BCT244

96 mA

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

SN74BCT244

128 mA

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Operating free-air temperature range:

SN54BCT244

– 55

°

C to 125

°

C

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

SN74BCT244

0

°

C to 70

°

C

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

Storage temperature range

– 65

°

C to 150

°

C

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 

‡ Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and

functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not

implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

NOTE 1: The input and output voltage ratings may be exceeded if the input and output current ratings are observed.

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 SN54BCT244, SN74BCT244

 OCTAL BUFFERS/DRIVERS

 WITH 3-STATE OUTPUTS

 SCBS006E – OCTOBER 1987 – REVISED APRIL 1994

2–3

POST OFFICE BOX 655303 

 DALLAS, TEXAS 75265

recommended operating conditions

SN54BCT244

SN74BCT244

UNIT

MIN

NOM

MAX

MIN

NOM

MAX

UNIT

VCC

Supply voltage

4.5

5

5.5

4.5

5

5.5

V

VIH

High-level input voltage

2

2

V

VIL

Low-level input voltage

0.8

0.8

V

IIK

Input clamp current

–18

–18

mA

IOH

High-level output current

– 12

– 15

mA

IOL

Low-level output current

48

64

mA

TA

Operating free-air temperature

– 55

125

0

70

°

C

electrical characteristics over recommended operating free-air temperature range (unless

otherwise noted)

PARAMETER

TEST CONDITIONS

SN54BCT244

SN74BCT244

UNIT

PARAMETER

TEST CONDITIONS

MIN

TYP†

MAX

MIN

TYP†

MAX

UNIT

VIK

VCC = 4.5 V,

II = –18 mA

–1.2

–1.2

V

IOH = – 3 mA

2.4

3.3

2.4

3.3

VOH

VCC = 4.5 V

IOH = – 12 mA

2

3.2

V

IOH = – 15 mA

2

3.1

VOL

VCC = 4 5 V

IOL = 48 mA

0.38

0.55

V

 VOL

VCC = 4.5 V

IOL = 64 mA

0.42

0.55

V

II

VCC = 5.5 V,

VI = 7 V

0.1

0.1

mA

IIH

VCC = 5.5 V,

VI = 2.7 V

20

20

µ

A

IIL

VCC = 5.5 V,

VI = 0.5 V

– 1

– 1

mA

IOZH

VCC = 5.5 V,

VO = 2.7 V

50

50

µ

A

IOZL

VCC = 5.5 V,

VO = 0.5 V

– 50

– 50

µ

A

IOS‡

VCC = 5.5 V,

VO = 0

– 100

– 225

– 100

– 225

mA

ICCH

VCC = 5.5 V,

Outputs open

23

40

23

40

mA

ICCL

VCC = 5.5 V,

Outputs open

53

80

53

80

mA

ICCZ

VCC = 5.5 V,

Outputs open

4

10

4

10

mA

† All typical values are at VCC = 5 V.

‡ Not more than one output should be tested at a time, and the duration of the test should not exceed one second.

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SN54BCT244, SN74BCT244

OCTAL BUFFERS/DRIVERS

WITH 3-STATE OUTPUTS

SCBS006E – OCTOBER 1987 – REVISED APRIL 1994

2–4

POST OFFICE BOX 655303 

 DALLAS, TEXAS 75265

switching characteristics (see Note 2)

PARAMETER

FROM

(INPUT)

TO

(OUTPUT)

VCC = 5 V,

CL = 50 pF,

R1 = 500 

,

R2 = 500 

,

TA = 25

°

C

VCC = 4.5 V to 5.5 V,

CL = 50 pF,

R1 = 500 

,

R2 = 500 

,

TA = MIN to MAX†

UNIT

BCT244

SN54BCT244

SN74BCT244

MIN

TYP

MAX

MIN

MAX

MIN

MAX

tPLH

A

Y

1.2

2.5

4.4

0.9

5.3

0.9

5

ns

tPHL

A

Y

1.7

3.2

5

1.4

6

1.4

5.5

ns

tPZH

OE

Y

2

5.7

7.8

2

9

2

8.7

ns

tPZL

OE

Y

2

5.9

8.1

2

9.4

2

8.9

ns

tPHZ

OE

Y

2

5.4

6.7

2

8

2

7.7

ns

tPLZ

OE

Y

2

6.1

7.6

2

9.8

2

8.9

ns

† For conditions shown as MIN or MAX, use the appropriate value specified under recommended operating conditions.

NOTE 2: Load circuits and voltage waveforms are shown in Section 1.

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accordance with TI’s standard warranty. Testing and other quality control techniques are utilized to the extent

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Copyright 

©

 1998, Texas Instruments Incorporated