TIDUEJ8C January   2019  – May 2024

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
    3. 2.3 Highlighted Products
      1. 2.3.1 MSPM0G1506
      2. 2.3.2 LMG2100R044
      3. 2.3.3 INA241
      4. 2.3.4 TPSM365
      5. 2.3.5 TMP303
    4. 2.4 System Design Theory
      1. 2.4.1 MPPT Operation
      2. 2.4.2 Buck Converter
        1. 2.4.2.1 Output Inductance
        2. 2.4.2.2 Input Capacitance
      3. 2.4.3 Current Sense Amplifier
        1. 2.4.3.1 Shunt Resistor Selection
        2. 2.4.3.2 Current Measurement Resolution
        3. 2.4.3.3 Shunt Resistor Power Dissipation
      4. 2.4.4 Switching Regulator
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Required Hardware and Software
      1. 3.1.1 Hardware
        1. 3.1.1.1 TIDA-010042
        2. 3.1.1.2 ITECH-IT6724H
        3. 3.1.1.3 Chroma, 63107A
      2. 3.1.2 Software Flow
    2. 3.2 Testing and Results
      1. 3.2.1 Test Setup
      2. 3.2.2 Test Results
  10. 4Design Files
    1. 4.1 Schematics
    2. 4.2 Bill of Materials
    3. 4.3 PCB Layout Recommendations
      1. 4.3.1 Loop Inductances
      2. 4.3.2 Current Sense Amplifiers
      3. 4.3.3 Trace Widths
      4. 4.3.4 Layout Prints
    4. 4.4 Altium Project
    5. 4.5 Gerber Files
    6. 4.6 Assembly Drawings
    7. 4.7 Software Files
  11. 5Related Documentation
    1. 5.1 Trademarks
    2. 5.2 Support Resources
  12. 6About the Author
  13. 7Revision History

2.3.3 INA241

TIDA-010042 INA241 Example ApplicationFigure 2-4 INA241 Example Application

The INA241 is an 110V, zero-drift current sense amplifier with enhanced PWM rejection.

  • Enhanced PWM Rejection
  • Excellent CMRR:
    • 166dB DC CMRR
    • 104dB AC CMRR at 100kHz
  • Wide Common-Mode Range: –5V to 110V
  • Accuracy:
    • Gain:
      • Version A: ±0.01%, ±1ppm/°C drift (Maximum)
      • Version B: ±0.1%, ±5ppm/°C drift (Maximum)
    • Offset:
      • Version A: ±10µV, ±0.1µV/°C drift (Maximum)
      • Version B: ±150µV, ±0.5µV/°C drift (Maximum)
  • Available Gains:
    • INA241A1, INA241B1 : 10V/V
    • INA241A2, INA241B2 : 20V/V
    • INA241A3, INA241B3 : 50V/V
    • INA241A4, INA241B4 : 100V/V
    • INA241A5, INA241B5 : 200V/V
  • Quiescent Current: 3.2mA (Maximum)

The high common mode voltage (110V) allows for support of various battery systems without sacrificing accuracy and the negative common mode voltage (–5V) allows the device to operate below ground to accommodate flyback.

The INA241 device is offered with 5 preset gain values of 10-, 20-, 50-, 100-, and 200V/V with a maximum gain error of 0.1%. With support for a maximum system current of 16A, the A4 (100V/V gain) variation is used in this design to maximize current reading resolution and minimize power dissipation through the shunt resistor.