SCLS383N September   1997  – October 2015 SN74LV244A

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  6. Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information
    5. 6.5  Electrical Characteristics
    6. 6.6  Noise Characteristics
    7. 6.7  Operating Characteristics
    8. 6.8  Switching Characteristics: VCC = 2.5 V ± 0.2 V
    9. 6.9  Switching Characteristics: VCC = 3.3 V ± 0.3 V
    10. 6.10 Switching Characteristics: VCC = 5 V ± 0.5 V
    11. 6.11 Typical Characteristics
  7. Parameter Measurement Information
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
    4. 8.4 Device Functional Modes
  9. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curve
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Community Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

パッケージ・オプション

デバイスごとのパッケージ図は、PDF版データシートをご参照ください。

メカニカル・データ(パッケージ|ピン)
  • DGV|20
  • DB|20
  • NS|20
  • DW|20
  • PW|20
  • RGY|20
サーマルパッド・メカニカル・データ
発注情報

8 Detailed Description

8.1 Overview

The SN74LV244 devices are octal buffers grouped in fours, with each group having its own enable pin. The LV family supports high current drive of about 16 mA, thus making it suitable for driving digital signals over longer board lengths. This device is generally used to buffer or incorporate delays between the signals between two microcontroller or peripheral devices.

8.2 Functional Block Diagram

SN74LV244A logic_cls383.gif

8.3 Feature Description

The SN74LV244A, a part of LV family, can work over a wide voltage range from 2 V to 5.5 V. The device features a very low propagation delay of about 6.5 ns when enabled for 5-V VCC, which allows the device to be used for high-speed applications. The device supports a partial-power-down mode for low quiescent current application, thus making it the buffer of choice in power-efficient circuits. The Ioff circuitry also disables the outputs, preventing damaging current backflow through the devices when they are powered down.

8.4 Device Functional Modes

The SN74LV244A devices are organized as two 4-bit 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. To ensure the high-impedance state during power up or power down, OE must be tied to VCC through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.

Table 1. Function Table

INPUTS OUTPUTS
OE A Y
L L L
L H H
H X Z