SCAS581N November   1996  – November 2014 SN74LVCR2245A

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Simplified Schematic
  5. 5 Revision History
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 Handling Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Switching Characteristics, -40°C to 85°C
    7. 7.7 Switching Characteristics, -40°C to 125°C
    8. 7.8 Operating Characteristics
    9. 7.9 Typical Characteristics
  8. 8 Parameter Measurement Information
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
    4. 9.4 Device Functional Modes
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Trademarks
    2. 13.2 Electrostatic Discharge Caution
    3. 13.3 Glossary

封装选项

请参考 PDF 数据表获取器件具体的封装图。

机械数据 (封装 | 引脚)
  • DGV|20
  • DB|20
  • DBQ|20
  • NS|20
  • PW|20
  • DW|20
  • RGY|20
散热焊盘机械数据 (封装 | 引脚)
订购信息

9 Detailed Description

9.1 Overview

This octal bus transceiver is designed for 1.65-V to 3.6-V VCC operation.

The SN74LVCR2245A device is designed for asynchronous communication between data buses. The device transmits data from the A bus to the B bus or from the B bus to the A bus, depending on the logic level at the direction-control (DIR) input. The output-enable (OE) input can be used to disable the device so the buses are effectively isolated.

All outputs, which are designed to sink up to 12 mA, include equivalent 26-Ω resistors to reduce overshoot and undershoot.

Inputs can be driven from either 3.3-V or 5-V devices. This feature allows the use of this device as a translator in a mixed 3.3-V/5-V system environment.

This device is fully specified for partial-power-down applications using Ioff. The Ioff circuitry disables the outputs, preventing damaging current backflow through the device when it is powered down.

To ensure the high-impedance state during power up or power down, OE should be tied to VCC through a pullup resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.

9.2 Functional Block Diagram

ld_cas581.gifFigure 4. Logic Diagram (Positive Logic)

9.3 Feature Description

  • Wide operating voltage range
    • Operates from 1.65 V to 3.6 V
  • Allows down-voltage translation
    • Inputs accept voltages to 5.5 V
  • Ioff feature
    • Allows voltages on the inputs and outputs when VCC is 0 V

9.4 Device Functional Modes

Table 2. Function Table

INPUTS OPERATION
OE DIR
L L B data to A bus
L H A data to B bus
H X Isolation