SLYY234 December   2024 AMC0106M05 , AMC0106M25 , AMC0136 , AMC0311D , AMC0311S , AMC0386 , AMC0386-Q1 , AMC1100 , AMC1106M05 , AMC1200 , AMC1200-Q1 , AMC1202 , AMC1203 , AMC1204 , AMC1211-Q1 , AMC1300 , AMC1300B-Q1 , AMC1301 , AMC1301-Q1 , AMC1302-Q1 , AMC1303M2510 , AMC1304L25 , AMC1304M25 , AMC1305M25 , AMC1305M25-Q1 , AMC1306M05 , AMC1306M25 , AMC1311 , AMC1311-Q1 , AMC131M03 , AMC1336 , AMC1336-Q1 , AMC1350 , AMC1350-Q1 , AMC23C12 , AMC3301 , AMC3330 , AMC3330-Q1

 

  1.   1
  2.   Introduction
  3.   Introduction to Isolated Signal Chain
    1.     Comparing Isolated Amplifiers and Isolated Modulators
      1.      Abstract
      2.      Introduction to Isolated Amplifiers
      3.      Introduction to Isolated Modulators
      4.      Performance Comparison Between Isolated Amplifiers and Isolated Modulators
      5.      Isolated Modulators in Traction Inverters
      6.      Isolated Amplifier and Modulator Recommendations
      7.      Conclusion
    2.     TI’s First Isolated Amplifiers With Ultra-Wide Creepage and Clearance
      1.      Application Brief
  4.   Selection Trees
  5.   Current Sensing
    1.     Shunt Resistor Selection for Isolated Data Converters
      1.      17
    2.     Design considerations for isolated current sensing
      1.      19
      2.      Conclusion
      3.      References
      4.      Related Websites
    3.     Isolated Current-Sensing Circuit With ±50-mV Input and Single-Ended Output
      1.      24
    4.     Isolated Current-Sensing Circuit With ±50-mV Input and Differential Output
      1.      26
    5.     Isolated Current-Sensing Circuit With ±250-mV Input Range and Single-Ended Output Voltage
      1.      Design Goals
      2.      Design Description
      3.      Design Notes
      4.      Design Steps
      5.      Design Simulations
      6.      DC Simulation Results
      7.      Closed-Loop AC Simulation Results
      8.      Transient Simulation Results
      9.      Design References
      10.      Design Featured Isolated Amplifier
      11.      Design Alternate Isolated Amplifier
    6.     Isolated current-measurement circuit with ±250-mV input and differential output
      1.      Design Goals
      2.      Design Description
      3.      Design Notes
      4.      Design Steps
      5.      Design Simulations
      6.      DC Simulation Results
      7.      Closed Loop AC Simulation Results
      8.      Transient Simulation Results
      9.      Design References
      10.      Design Featured Op Amp
      11.      Design Alternate Op Amp
    7.     Isolated Overcurrent Protection Circuit
      1.      52
    8.     Interfacing a Differential-Output (Isolated) Amp to a Single-Ended Input ADC
      1.      54
    9.     Utilizing AMC3311 to Power AMC23C11 for Isolated Sensing and Fault Detection
      1.      Application Brief
    10.     Isolated Current-Sensing Circuit With Front-End Gain Stage
      1.      58
    11.     Accuracy Comparison of Isolated Shunt and Closed-Loop Current Sensing
      1.      60
  6.   Voltage Sensing
    1.     Maximizing Power Conversion and Motor Control Efficiency With Isolated Voltage Sensing
      1.      63
      2.      Solutions for high-voltage sensing
      3.      Integrated resistor devices
      4.      Single-ended output devices
      5.      Integrated isolated voltage-sensing use cases
      6.      Conclusion
      7.      Additional resources
    2.     Increased Accuracy and Performance with Integrated High Voltage Resistor Isolated Amplifiers and Modulators
      1.      Abstract
      2.      Introduction
      3.      High Voltage Resistor Isolated Amplifiers and Modulators Advantages
        1.       Space Savings
        2.       Improved Temperature and Lifetime Drift of Integrated HV Resistors
        3.       Accuracy Results
        4.       Fully Integrated Resistors vs. Additional External Resistor Example
        5.       Device Selection Tree and AC/DC Common Use Cases
      4.      Summary
      5.      References
    3.     Isolated Amplifiers With Differential, Single-Ended Fixed Gain and Ratiometric Outputs for Voltage Sensing Applications
      1.      Abstract
      2.      Introduction
      3.      Overview of Differential, Single-Ended Fixed Gain and Ratiometric Outputs
        1.       Isolated Amplifiers with Differential Output
        2.       Isolated Amplifiers With Single-Ended, Fixed-Gain Output
        3.       Isolated Amplifiers With Single-Ended, Ratiometric Output
      4.      Application Examples
        1.       Product Selection Tree
      5.      Summary
      6.      References
    4.     Isolated Voltage-Measurement Circuit With ±250-mV Input and Differential Output
      1.      93
    5.     Split-Tap Connection for Line-to-Line Isolated Voltage Measurement Using AMC3330
      1.      95
    6.     ±12V Voltage Sensing Circuit With an Isolated Amplifier and Pseudo-Differential Input SAR ADC
      1.      97
    7.     ±12-V voltage sensing circuit with an isolated amplifier and differential input SAR ADC
      1.      99
    8.     Isolated Undervoltage and Overvoltage Detection Circuit
      1.      101
    9.     Isolated Zero-Cross Detection Circuit
      1.      103
    10.     ±480V Isolated Voltage-Sensing Circuit With Differential Output
      1.      105
  7.   EMI Performance
    1.     Best in Class Radiated Emissions EMI Performance with Isolated Amplifiers
      1.      Best in Class Radiated Emissions EMI Performance with Isolated Amplifiers
      2.      Introduction
      3.      Current Generation of Texas Instruments Isolated Amplifiers Radiated Emissions Performance
      4.      Previous Generations of Texas Instruments Isolated Amplifiers Radiated Emissions Performance
      5.      Conclusion
      6.      References
    2.     Best Practices to Attenuate AMC3301 Family Radiated Emissions EMI
      1.      Abstract
      2.      Introduction
      3.      Effects of Input Connections on AMC3301 Family Radiated Emissions
      4.      Attenuating AMC3301 Family Radiated Emissions
        1.       Ferrite Beads and Common Mode Chokes
        2.       PCB Schematics and Layout Best Practices for AMC3301 Family
      5.      Using Multiple AMC3301 Devices
        1.       Device Orientation
        2.       PCB Layout Best Practices for Multiple AMC3301
      6.      Conclusion
      7.      AMC3301 Family Table
  8.   End Equipment
    1.     Comparing Shunt- and Hall-Based Isolated Current-Sensing Solutions in HEV/EV
      1.      128
    2.     Design Considerations for Current Sensing in DC EV Charging Applications
      1.      Abstract
      2.      Introduction
        1.       DC Charging Station for Electric Vehicles
        2.       Current-Sensing Technology Selection and Equivalent Model
          1.        Sensing of the Current With Shunt-Based Solution
          2.        Equivalent Model of the Sensing Technology
      3.      Current Sensing in AC/DC Converters
        1.       Basic Hardware and Control Description of AC/DC
          1.        AC Current Control Loops
          2.        DC Voltage Control Loop
        2.       Point A and B – AC/DC AC Phase-Current Sensing
          1.        Impact of Bandwidth
            1.         Steady State Analysis: Fundamental and Zero Crossing Currents
            2.         Transient Analysis: Step Power and Voltage Sag Response
          2.        Impact of Latency
            1.         Fault Analysis: Grid Short-Circuit
          3.        Impact of Gain Error
            1.         Power Disturbance in AC/DC Caused by Gain Error
            2.         AC/DC Response to Power Disturbance Caused by Gain Error
          4.        Impact of Offset
        3.       Point C and D – AC/DC DC Link Current Sensing
          1.        Impact of Bandwidth on Feedforward Performance
          2.        Impact of Latency on Power Switch Protection
          3.        Impact of Gain Error on Power Measurement
            1.         Transient Analysis: Feedforward in Point D
          4.        Impact of Offset
        4.       Summary of Positives and Negatives at Point A, B, C1/2 and D1/2 and Product Suggestions
      4.      Current Sensing in DC/DC Converters
        1.       Basic Operation Principle of Isolated DC/DC Converter With Phase-Shift Control
        2.       Point E, F - DC/DC Current Sensing
          1.        Impact of Bandwidth
          2.        Impact of Gain Error
          3.        Impact of Offset Error
        3.       Point G - DC/DC Tank Current Sensing
        4.       Summary of Sensing Points E, F, and G and Product Suggestions
      5.      Conclusion
      6.      References
    3.     Using isolated comparators for fault detection in electric motor drives
      1.      Introduction
      2.      Introduction to electric motor drives
      3.      Understanding fault events in electric motor drives
      4.      Achieving reliable detection and protection in electric motor drives
      5.      Use case No. 1: Bidirectional in-phase overcurrent detection
      6.      Use case No. 2: DC+ overcurrent detection
      7.      Use case No. 3: DC– overcurrent or short-circuit detection
      8.      Use case No. 4: DC-link (DC+ to DC–) overvoltage and undervoltage detection
      9.      Use case No. 5: IGBT module overtemperature detection
    4.     Discrete DESAT for Opto-Compatible Isolated Gate Driver UCC23513 in Motor Drives
      1.      Abstract
      2.      Introduction
      3.      System Challenge on Isolated Gate Drivers With Integrated DESAT
      4.      System Approach With UCC23513 and AMC23C11
        1.       System Overview and Key Specification
        2.       Schematic Design
          1.        Circuit Schematic
          2.        Configure VCE(DESAT) Threshold and DESAT Bias Current
          3.        DESAT Blanking Time
          4.        DESAT Deglitch Filter
        3.       Reference PCB Layout
      5.      Simulation and Test Results
        1.       Simulation Circuit and Results
          1.        Simulation Circuit
          2.        Simulation Results
        2.       Test Results With 3-Phase IGBT Inverter
          1.        Brake IGBT Test
          2.        Test Results on a 3-Phase Inverter With Phase to Phase Short
      6.      Summary
      7.      References
    5.     Isolated voltage sensing in AC motor drives
      1.      Introduction
      2.      Conclusion
      3.      References
    6.     Achieving High-Performance Isolated Current and Voltage Sensing in Server PSUs
      1.      Application Brief
  9.   Additional Reference Designs/Circuits
    1.     Designing a Bootstrap Charge-Pump Power Supply for an Isolated Amplifier
      1.      Abstract
      2.      Introduction
      3.      Bootstrap Power Supply Design
        1.       Selection of Charge Pump Capacitor
        2.       Simulation in TINA-TI
        3.       Hardware Test with AMC1311-Q1
      4.      Summary
      5.      Reference
    2.     Clock Edge Delay Compensation With Isolated Modulators Digital Interface to MCUs
      1.      Abstract
      2.      Introduction
      3.      Design Challenge With Digital Interface Timing Specifications
      4.      Design Approach With Clock Edge Delay Compensation
        1.       Clock Signal Compensation With Software Configurable Phase Delay
        2.       Clock Signal Compensation With Hardware Configurable Phase Delay
        3.       Clock Signal Compensation by Clock Return
        4.       Clock Signal Compensation by Clock Inversion at the MCU
      5.      Test and Validation
        1.       Test Equipment and Software
        2.       Testing of Clock Signal Compensation With Software Configurable Phase Delay
          1.        Test Setup
          2.        Test Measurement Results
        3.       Testing of Clock Signal Compensation by Clock Inversion at MCU
          1.        Test Setup
          2.        Test Measurement Results
            1.         Test Result – No Clock Inversion of Clock Input at GPIO123
            2.         Test Result – Clock Inversion of Clock Input at GPIO123
        4.       Digital Interface Timing Validation by Calculation Tool
          1.        Digital Interface With No Compensation Method
          2.        Commonly Used Method - Reduction of the Clock Frequency
          3.        Clock Edge Compensation With Software Configurable Phase Delay
      6.      Conclusion
      7.      References
    3.     Utilizing AMC3311 to Power AMC23C11 for Isolated Sensing and Fault Detection
      1.      Application Brief

Introduction

In isolated amplifiers with a capacitive isolation barrier, radiated emissions can be created when the capacitors that span the barrier are charged and discharged to transmit data in the form of either a 1 or a 0. The charges flow through the differential capacitors in opposite directions mostly canceling each other, however any difference in magnitude or time between these charge flows results in electro-magnetic energy injected between the isolated grounds GND1 and GND2. Because of the nature of the isolation barrier, the energy is unable to find a conductor to return to the source. With no path back to the source, the energy radiates from the device pins (and any traces or PCB planes they are connected to) in the form of radiated emissions. This radiation can extend to frequencies significantly above the amplifier signal bandwidth and data rates, since it is caused by timing mismatches in the pico-second range.

Isolated Amplifier Block DiagramFigure 53 Isolated Amplifier Block Diagram

Within the recent years, there have been significant improvements to the architecture of Texas Instruments isolated amplifiers to optimize radiated EMI performance. Beginning in 2018 with the ISO224, isolated amplifiers from Texas Instruments began to use on or off keying (OOK) signal modulation compared to previously used pulse coding. The OOK modulation enabled significantly improved Common-Mode Transient Immunity levels. Then in 2020, the AMC1300B-Q1 was the first isolated amplifier that significantly reduced the amount of energy crossing over the isolation barrier, which reduces the radiated emissions, providing sufficient margins to the standard specifications. These design changes, as well as a re-designed isolated signal path, are now present in the entire Texas Instruments isolated amplifier portfolio, with the exception of the AMC1100, AMC1200, and ISO224 devices. The optimized timing and amplitude in the signal chain yields a reduction of radiated emissions EMI at high frequencies to an even lower level.

The following sections show the radiated emissions EMI performance for the Texas Instruments' isolated amplifiers. The current generation of isolated amplifiers radiated emissions performance is shown by using the AMC1300B-Q1 as an example, while the ISO224 and AMC1200 are used to show data for the previous generation devices. The radiated emissions scans were all performed according to the standards set in place by CISPR 11. All tests were performed using the AMC1300EVM printed circuit board (PCB) with the inputs shorted to ground, transformer driver (U3) removed, and external 3.6 V batteries with short leads. Each scan shows the horizontal sweep results from the device under test (DUT) in blue as well as the ambient scan overlaid in red to show the noise floor of the chamber. Both CISPR 11 Class A and Class B limits are shown on the plots as well. The horizontal polarization was selected because the emissions levels detected by the test equipment’s antenna were higher than for the vertical polarization, due to alignment with the PCB.