GD74LS244 Octal 3-STATE Buffer/Line Driver/Line Receiver IC

GD74LS244 Octal 3-STATE
Buffer/Line Driver/Line Receiver
IC

The GD74LS244 is a monolithic integrated circuit from the LS-TTL family, functioning as an octal buffer, line driver, and line receiver. This single IC contains eight individual buffers, organized into two groups of four, with each group controlled by a separate output enable pin. Its primary design purpose is to enhance the performance and density of digital systems by providing a robust interface between a data source and a common bus or transmission line. It acts as a signal amplifier, ensuring that a logic signal can be transmitted over longer distances or to more devices without degradation.

A key characteristic of this device is its non-inverting 3-state output. The outputs can exist in one of three states: a standard logic high, a standard logic low, or a high-impedance (Hi-Z) state. When the output is in the high-impedance state, it is effectively disconnected from the circuit, allowing multiple outputs to be connected to a shared bus line without causing electrical conflicts. This is essential for building bidirectional buses and multiplexed systems where multiple devices need to share the same data path.

The inputs of the
GD74LS244
are designed with P-N-P transistors, which significantly reduce the DC loading on the driving circuitry. Furthermore, the inputs incorporate hysteresis, which improves noise margins by requiring a defined voltage change to switch states, making the device more resistant to signal noise and fluctuations. Combined with its ability to drive relatively heavy loads, these features make it a reliable solution for driving memory address registers, clock lines, and other bus-oriented applications in noisy environments.

Features:

Non-inverting 3-State outputs for bus-oriented applications.

Separate output enable inputs for each group of four buffers.

P-N-P inputs to reduce DC loading on the source driver.

Input hysteresis improves noise immunity.

Designed to drive terminated transmission lines.

Pin Description:

Pin No

Pin Name

Description

1

1G

Channel 1 output enable

2

1A1

Channel 1, (A) side 1

3

2Y4

Channel 2, Y side 4

4

1A2

Channel 1, (A) side 2

5

2Y3

Channel 2, Y side 3

6

1A3

Channel 1, (A) side 3

7

2Y2

Channel 2, Y side 2

8

1A4

Channel 1, (A) side 4

9

2Y1

Channel 2, Y side 1

10

GND

Ground

11

2A1

Channel 2, (A) side 1

12

1Y4

Channel 1, Y side 4

13

2A2

Channel 2, (A) side 2

14

1Y3

Channel 1, Y side 3

15

2A3

Channel 2, (A) side 3

16

1Y2

Channel 1, Y side 2

17

2A4

Channel 2, (A) side 4

18

1Y1

Channel 1, Y side 1

19

2G

Channel 2 output enable

20

VCC

Positive Supply

Specifications:

Parameter

Condition

Min

Typ

Max

Unit

Supply Voltage (Vcc):

4.75

5

5.25

V

High-Level Input Voltage:

2

V

Low-Level Input Voltage:

0.8

V

Propagation Delay:

12

18

ns

Output Current (Low):

24

mA

Operating Temperature:

0

70

C

Footprint Diagram:

Applications:

Memory Address Driving.

Clock Driver.

Bus Transceiver.

System Bus Buffering.

General Purpose Line Driving.

Package Contents:

1x
GD74LS244 Octal 3-STATE Buffer/Line Driver/Line Receiver IC

Datasheet