SLUAB09 October   2025 AMC0386-Q1 , TPS61170 , TPS61170-Q1 , TPSI2140-Q1

 

  1.   1
  2.   Abstract
  3. 1Introduction
    1. 1.1 Background
    2. 1.2 System Requirements
    3. 1.3 Typical Challenges
      1. 1.3.1 Influence of Y-Capacitors
      2. 1.3.2 High Potential Testing
      3. 1.3.3 Wide AC Voltage Range
  4. 2Insulation Monitoring Architectures
    1. 2.1 Basic Architecture
    2. 2.2 Dual-Switch Architecture
    3. 2.3 Active Single-Switch Architecture
    4. 2.4 Architecture Comparison
  5. 3Key Components
    1. 3.1 Solid-State Relay
    2. 3.2 Voltage Sensor
    3. 3.3 DC Power Supply
  6. 4Summary
  7. 5Reference
  8.   Trademarks

2.4 Architecture Comparison

Based on the previous analysis and equivalent circuit, Table 2-1 summarizes the characteristics of the three IMD architectures.

Table 2-1 Architecture Comparison
Architecture Basic Dual switches Active single switch
Components Op-amp × 1 Switch × 2 + Op-amp × 1 Switch × 1 + Op-amp × 1 + DC bias × 1
Accuracy Low High Medium
Effort on software Low High Medium
Cost Low High Medium
Influence of Y-capacitor High Medium Low
Features Symmetric | Asymmetric fault No Yes Yes
Detect fault location Yes Yes No
Calculate insulation resistance No Yes No
Operate without AC voltage present No No Yes
Golden rule ( R i s o P - R i s o N ) ↑   → V i n ↑ R i s o P   ↓   → V i n   ↓ ,   R i s o N   ↓   → V i n ↑ R s y s ↑   → V i n ↑