JAJSES0 February   2018 XTR305

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     Device Images
      1.      代表的なアプリケーション
  4. 4 改訂履歴
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 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: Voltage Output Mode
    6. 6.6  Electrical Characteristics: Current Output Mode
    7. 6.7  Electrical Characteristics: Operational Amplifier (OPA)
    8. 6.8  Electrical Characteristics: Instrumentation Amplifier (IA)
    9. 6.9  Electrical Characteristics: Current Monitor
    10. 6.10 Electrical Characteristics: Power and Digital
    11. 6.11 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagrams
    3. 7.3 Feature Description
      1. 7.3.1 Functional Features
      2. 7.3.2 Current Monitor
      3. 7.3.3 Error Flags
      4. 7.3.4 Power On/Off Glitch
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1  Voltage Output Mode
        2. 8.2.2.2  Current Output Mode
        3. 8.2.2.3  Input Signal Connection
        4. 8.2.2.4  Externally-Configured Mode: OPA and IA
        5. 8.2.2.5  Driver Output Disable
        6. 8.2.2.6  Driving Capacitive Loads and Loop Compensation
        7. 8.2.2.7  Internal Current Sources, Switching Noise, and Settling Time
        8. 8.2.2.8  IA Structure, Voltage Monitor
        9. 8.2.2.9  Digital I/O and Ground Considerations
        10. 8.2.2.10 Output Protection
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 VQFN Package and Heat Sinking
    4. 10.4 Power Dissipation
  11. 11デバイスおよびドキュメントのサポート
    1. 11.1 ドキュメントのサポート
      1. 11.1.1 関連資料
    2. 11.2 ドキュメントの更新通知を受け取る方法
    3. 11.3 コミュニティ・リソース
    4. 11.4 商標
    5. 11.5 静電気放電に関する注意事項
    6. 11.6 Glossary
  12. 12メカニカル、パッケージ、および注文情報

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

8.2.2.1 Voltage Output Mode

In voltage output mode (M1 and M2 are connected low or left unconnected), the feedback loop through the IA provides high impedance remote sensing of the voltage at the destination, compensating the resistance of a protection circuit, switches, wiring, and connector resistance. The output of the IA is a current that is proportional to the input voltage. This current is internally routed to the OPA summing junction through a multiplexer, as shown in Figure 41.

A 1:10 copy of the output current of the OPA can be monitored at the IMON pin. This output current and the known output voltage can be used to calculate the load resistance or load power.

During an output short-circuit or an overcurrent condition the XTR305 output current is limited and EFLD (load error, active low) flag is activated.

XTR305 ai_vout_mode_simple_bos336.gifFigure 41. Simplified Voltage Output Mode Configuration

Applications not requiring the remote sense feature can use the OPA in stand-alone operation (M1 = high). In this case, the IA is available as a separate input channel.

The IA gain can be set by two resistors, RGAIN and RSET (Equation 1):

Equation 1. XTR305 q_vout_rgain_bos336.gif

or when adding an offset, VREF, to get bidirectional output with a single-ended input shown in Equation 2:

Equation 2. XTR305 q_vout_rgain02_bos336.gif

The RSET resistor is also used in current output mode. Therefore, it is useful to define RSET for the current mode, then set the ratio between current and voltage span with RGAIN.