SCDS019M May   1995  – December 2015 SN74CBT3251

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 Switching Characteristics
    7. 6.7 Typical Characteristic
  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

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)
  • PW|16
  • DB|16
  • DBQ|16
  • RGY|16
  • D|16
散热焊盘机械数据 (封装 | 引脚)
订购信息

8 Detailed Description

8.1 Overview

The SN74CBT3251 device is a single 8-channel multiplexer with three binary control inputs, S0, S1, and S2 and an OE (output enable, active low) input. The three binary signals select 1 of 8 channels to be turned on, and connect one of the 8 inputs to the output.

When they are used as demultiplexers, the CHANNEL IN/OUT terminals (B) are the outputs and the COMMON OUT/IN terminal (A) is the input.

8.2 Functional Block Diagram

SN74CBT3251 logic_diag.gif Figure 3. Logic Diagram (Positive Logic)

8.3 Feature Description

The SN74CBT3251 1-of-8 FET multiplexers and demultiplexers can accept a wide range of analog signal levels from 0 V to 5 V. It has low Ron resistance, typically 5-Ω for VCC = 5 V which allows very little signal loss through the switch. Binary address decoding on chip makes channel selection easy.

8.4 Device Functional Modes

Table 1 lists the functional modes of the SN74CBT3251.

Table 1. Function Table (Each Multiplexer and Demultiplexer)

INPUTS FUNCTION
OE S2 S1 S0
L L L L A port = B1 port
L L L H A port = B2 port
L L H L A port = B3 port
L L H H A port = B4 port
L H L L A port = B5 port
L H L H A port = B6 port
L H H L A port = B7 port
L H H H A port = B8 port
H X X X Disconnect