SDAA154 October   2025 AMC0300D , AMC0300D-Q1 , AMC0300R , AMC0300R-Q1 , AMC0306M05 , AMC0306M05-Q1 , AMC0306M25 , AMC0306M25-Q1 , AMC131M03 , AMC131M03-Q1 , AMC3301 , AMC3301-Q1 , AMC3302 , AMC3302-Q1 , AMC3306M05 , AMC3306M05-Q1 , AMC3306M25 , AMC3306M25-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Detailed Description
    1. 2.1 Cost Optimized Power Supplies
      1. 2.1.1 Transformer Winding
      2. 2.1.2 Gate Driver Supply with Zener Diode
      3. 2.1.3 Gate Driver Supply with LDO
    2. 2.2 Simplified Power Supplies:
      1. 2.2.1 Integrated DC/DC Converter Power Supply
      2. 2.2.2 Discrete Transformer
    3. 2.3 Isolated Current Sensing Locations in High Voltage Power Conversion
      1. 2.3.1 Introduction
      2. 2.3.2 Rectifier (AC to DC Converter)
      3. 2.3.3 DC/DC
      4. 2.3.4 Inverter (DC to AC Converter)
  6. 3Summary
  7. 4References

1 Introduction

Texas Instruments' AMC devices are a variety of isolated current and voltage sensing devices that are capable of withstanding high common-mode voltages. The integrated isolation barrier inherently separates a high-voltage side and a low-voltage side of a given device which each require an independent power supply. When determining an optimal high-side power supply for an AMC device and system, considerations may include cost, size, location, ease of use, isolation, and functional safety. This app note aims to summarize five recommended high-side power supply options for the seven main locations isolated current sensing is seen in high voltage power conversion. The high-side power supply options include three cost optimized power supply designs: transformer winding, gate driver supply with Zener diode, and gate driver supply with LDO and two simplified power supply designs: integrated DC/DC converter and discrete transformer. Then, this document outlines the seven main locations isolated current sensing in the rectifier, DC/DC, and inverter.

Table 1-1 High-Side Power Supply Options Comparison
Cost Optimized Power SuppliesSimplified Power Supplies
Transformer WindingGate Driver Supply with Zener DiodeGate Driver Supply with LDOIntegrated

DC/DC Converter

Discrete Transformer

Cost$$$1$1$$$$$
Size+++++++++
Ease of Use+++++++++++1
IsolationN/AN/AN/A+++
Functional Safety+++++++++
System RequirementsLow cost option with greater functional safety.Lowest cost option with less potential for overshoot.Low cost option with stable output and lower noise.Small footprint with great ease of use.Most customizable with great ease of use.
  1. Further differentiating factors included in System Requirements row.