SLYY234 E-book

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
Introduction
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
Selection Trees
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
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
  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
EMI Performance
1. Best in Class Radiated Emissions EMI Performance with Isolated Amplifiers
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
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
        
                Steady State Analysis: Fundamental and Zero Crossing Currents
        
                Transient Analysis: Step Power and Voltage Sag Response
      2. Impact of Latency
        
        Fault Analysis: Grid Short-Circuit
      3.        Impact of Gain Error
        
                Power Disturbance in AC/DC Caused by Gain Error
        
                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
        
        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
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
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
  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
        
                Test Result – No Clock Inversion of Clock Input at GPIO123
        
                Test Result – Clock Inversion of Clock Input at GPIO123
    4. Digital Interface Timing Validation by Calculation Tool
  6. Conclusion
  7. References
3. Utilizing AMC3311 to Power AMC23C11 for Isolated Sensing and Fault Detection
  1. Application Brief

Introduction

Several industrial and automotive applications such as on board chargers, solar inverters, DC charging (pile) stations, power conversion systems, and motor drives require isolation to protect the digital circuitry from the high-voltage circuit performing a measurement. Two ways to accomplish the isolated current sensing for these applications are isolated shunt based sensing and magnetic (Hall or flux-gate) based sensing. This document compares Texas Instruments AMC3302 a single-supply, isolated amplifier to a popular closed-loop current sensor (CLCS).

Technologies Overview

Figure 24 Isolated Shunt Based Current Sensing. Isolated shunt based current sensing relies on measuring a voltage across a precise in-line resistor, known as a shunt resistor.

The shunt resistance must be very accurate in order to produce the expected voltage for the supplied current, as any variation in expected resistance will contribute directly to a gain error. The benefit of shunt based current sensing is that it allows for industry leading accuracy, immunity to magnetic interference, scalability and small size.

Figure 25 Hall Based Closed-Loop Sensor. CLCS uses a magnetic core to sense the magnetic field created by the current passing through the primary conductor. The magnetic field sensing element included in the CLCS is used to provide a compensation current that is applied to the magnetic core. This compensation current creates a flux that is equal in magnitude, but in the opposite direction of the flux created by the primary conductor; producing a zero-flux measurement. Magnetic based current sensing is vulnerable to magnetic interference which can affect the offset and linearity performance of the device.

Additional information comparing the two technologies can be found here.

Test Setup

Figure 26 AMC3302 Circuit and CLCS Test Setup Block Diagram. A test setup was created in order to directly compare the performance of these two technologies. A DC current source, electronic load and digital multi-meters were used to capture data for a +/-85A primary current sweep at three different temperatures; -40C, 25C and 85C. All measurements were automated according to IEEE488.

Please note that the 500µΩ Shunt 1 used for the AMC3302 circuit measurement and 500µΩ Shunt 2 used for the control measurement were not subjected to changes in ambient temperature, therefor the shunt temperature drift error is not included in this analysis. Both shunts are rated for ±0.25% tolerance, ±15ppm/°C temperature coefficient and 20W power dissipation.

Figure 27 AMC3302 Circuit Diagram.

The circuit diagram below shows the AMC3302 and TLV6002 circuit used for the accuracy comparison. Channel 1 of the TLV6002 was used to buffer a reference voltage generated via resistor divider while the differential output of the AMC3302 was converted from differential to single-ended via channel 2. Thus the AMC3302 circuit has an identical interface as the CLCS; VDD, GND, VREF and VOUT.

Figure 28 AMC3302 Circuit Printed Circuit Board.

Below is the AMC3302 Printed Circuit Board (PCB). The PCB was designed such that the AMC3302 circuit fits within the same x, y footprint as the CLCS, 13.4mm x 21.9mm. The AMC3302 PCB is much smaller in terms of height; 2.6mm compared to 16mm for the CLCS, a reduction in height of 84%.

Accuracy Comparison

Figure 6. shows the accuracy results for the +/-85A primary current sweep over temperature in terms of error as a percentage of full-scale output after a 25C offset calibration. The AMC3302 circuit results are shown in shades of red and the CLCS in blue. The AMC3302 circuit is very accurate over the full current and temperature range without gain calibration, better than 0.1%. The CLCS shows worse gain error drift and linearity performance compared to the AMC3302 circuit, resulting in an overall error greater than 0.5%. The AMC3302 circuit offers an accuracy improvement of more than 5x compared to the CLCS over the full current and temperature range.

Figure 29 Accuracy Comparison for AMC3302 Circuit and Closed-loop Current Sensor After Offset Calibration.

Below shows an accuracy comparison table of absolute maximum error.

Temperature	-40C	25C	85C
AMC3302 Circuit	-0.077%	-0.029%	0.035%
CLCS	-0.356%	-0.492%	-0.573%

Conclusion

The table below summarizes the comparison of the AMC3302 circuit and the CLCS. For systems requiring industry leading accuracy, the AMC3302 circuit shows a clear advantage compared to the CLCS. The size of the AMC3302 circuit used for this comparison is equal size in terms of x and y dimensions, while showing a clear advantage in terms of height, z. The AMC3302 circuit also offers immunity to magnetic interference, as well as scalability.

	AMC3302 Circuit	CLCS
Accuracy	++	+
Size	+	-
Magnetic Immunity	++	--
Scalability	++	-
Ease of Design	+	++