ZHCSI82E May   2018  – May 2019 THVD1410 , THVD1450 , THVD1451 , THVD1452

PRODUCTION DATA.  

  1. 1 特性
  2. 2 应用
  3. 3 说明
    1.     Device Images
      1.      THVD1410 和 THVD1450 简化原理图
      2.      THVD1451 简化原理图
      3.      THVD1452 简化原理图
  4. 4 修订历史记录
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
    2.     Pin Functions
    3.     Pin Functions
  7. 7 Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings
    3. 7.3  ESD Ratings [IEC]
    4. 7.4  Recommended Operating Conditions
    5. 7.5  Thermal Information
    6. 7.6  Power Dissipation
    7. 7.7  Electrical Characteristics
    8. 7.8  Switching Characteristics
    9. 7.9  Typical Characteristics: All Devices
    10. 7.10 Typical Characteristics: THD1450, THVD1451 and THVD1452
    11. 7.11 Typical Characteristics: THVD1410
  8. 8 Parameter Measurement Information
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagrams
    3. 9.3 Feature Description
    4. 9.4 Device Functional Modes
      1. 9.4.1 Device Functional Modes for THVD1410 and THVD1450
      2. 9.4.2 Device Functional Modes for THVD1451
      3. 9.4.3 Device Functional Modes for THVD1452
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
        1. 10.2.1.1 Data Rate and Bus Length
        2. 10.2.1.2 Stub Length
        3. 10.2.1.3 Bus Loading
        4. 10.2.1.4 Receiver Failsafe
        5. 10.2.1.5 Transient Protection
      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. 13器件和文档支持
    1. 13.1 器件支持
    2. 13.2 第三方产品免责声明
    3. 13.3 相关链接
    4. 13.4 接收文档更新通知
    5. 13.5 社区资源
    6. 13.6 商标
    7. 13.7 静电放电警告
    8. 13.8 Glossary
  14. 14机械、封装和可订购信息

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)
  • D|8
  • DGK|8
散热焊盘机械数据 (封装 | 引脚)
订购信息

10.2.1.4 Receiver Failsafe

The differential receivers of the THVD14xx family are failsafe to invalid bus states caused by the following:

  • Open bus conditions, such as a disconnected connector
  • Shorted bus conditions, such as cable damage shorting the twisted-pair together
  • Idle bus conditions that occur when no driver on the bus is actively driving

In any of these cases, the differential receiver will output a failsafe logic high state so that the output of the receiver is not indeterminate.

Receiver failsafe is accomplished by offsetting the receiver thresholds such that the input indeterminate range does not include zero volts differential. In order to comply with the RS-422 and RS-485 standards, the receiver output must output a high when the differential input VID is more positive than 200 mV, and must output a Low when VID is more negative than –200 mV. The receiver parameters which determine the failsafe performance are VTH+, VTH–, and VHYS (the separation between VTH+ and VTH–). As shown in the table, differential signals more negative than –200 mV will always cause a low receiver output, and differential signals more positive than 200 mV will always cause a high receiver output.

When the differential input signal is close to zero, it is still above the VTH+ threshold, and the receiver output will be High. Only when the differential input is more than VHYS below VTH+ will the receiver output transition to a Low state. Therefore, the noise immunity of the receiver inputs during a bus fault conditions includes the receiver hysteresis value, VHYS, as well as the value of VTH+.