JAJSNR9B April   2016  – April 2022 INA301-Q1

PRODUCTION DATA  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
  4. 4 Revision History
  5. 5 Pin Configuration and 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
    6. 6.6 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Alert Output ( ALERT Pin)
      2. 7.3.2 Current-Limit Threshold
        1. 7.3.2.1 Resistor-Controlled Current Limit
          1. 7.3.2.1.1 Resistor-Controlled, Current-Limit Example
        2. 7.3.2.2 Voltage-Source-Controlled Current Limit
      3. 7.3.3 Hysteresis
    4. 7.4 Device Functional Modes
      1. 7.4.1 Alert Mode
        1. 7.4.1.1 Transparent Output Mode
        2. 7.4.1.2 Latch Output Mode
  8. 8 Applications and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Selecting a Current-Sensing Resistor
        1. 8.1.1.1 Selecting a Current-Sensing Resistor Example
      2. 8.1.2 Input Filtering
      3. 8.1.3 INA301-Q1 Operation With Common-Mode Voltage Transients Greater Than 36 V
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curve
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 サポート・リソース
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

7.3.2.1 Resistor-Controlled Current Limit

The typical method for setting the limit threshold voltage is to connect a resistor from the LIMIT pin to ground. The value of this resistor, RLIMIT, is chosen in order to create a corresponding voltage at the LIMIT pin equivalent to the output voltage, VOUT, when the maximum desired load current is flowing through the current-sensing resistor. An internal 80-µA current source is connected to the LIMIT pin to create a corresponding voltage used to compare to the amplifier output voltage, depending on the value of the RLIMIT resistor.

In the equations from Table 7-1, VTRIP represents the overcurrent threshold that the device is programmed to monitor, and VLIMIT is the programmed signal set to detect the VTRIP level.

Table 7-1 Calculating the Threshold-Limit-Setting Resistor, RLIMIT
PARAMETEREQUATION
VTRIPVOUT at the desired-current trip valueILOAD × RSENSE x Gain
VLIMITThreshold limit voltageVLIMIT = VTRIP
ILIMIT × RLIMIT
RLIMITThreshold limit-setting resistor valueVLIMIT / ILIMIT
VLIMIT / 80 µA