SBASAB0 December   2021 AMC1350-Q1

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  6. Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information
    5. 6.5  Power Ratings
    6. 6.6  Insulation Specifications
    7. 6.7  Safety-Related Certifications
    8. 6.8  Safety Limiting Values
    9. 6.9  Electrical Characteristics
    10. 6.10 Switching Characteristics
    11. 6.11 Timing Diagram
    12. 6.12 Insulation Characteristics Curves
    13. 6.13 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Analog Input
      2. 7.3.2 Isolation Channel Signal Transmission
      3. 7.3.3 Analog Output
    4. 7.4 Device Functional Modes
  8. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Input Filter Design
        2. 8.2.2.2 Differential to Single-Ended Output Conversion
      3. 8.2.3 Application Curve
    3. 8.3 What To Do and What Not To Do
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary

Typical Application

Isolated amplifiers are widely used for voltage measurements in high-voltage applications that must be isolated from a low-voltage domain. Typical applications are AC line voltage measurements, either line-to-neutral or line-to-line in grid-connected equipment.

Figure 8-1 illustrates a simplified schematic of an onboard charger (OBC) application that uses three AMC1350-Q1 devices to measure the AC line voltage on each phase of a three-phase system. The AC line voltage is divided down to an approximate ±5-V level across the bottom resistor (RSNS) of a high-impedance resistive divider that is sensed by the AMC1350-Q1. The output of the AMC1350-Q1 is a differential analog output voltage proportional to the input voltage but is galvanically isolated from the high-side by a reinforced isolation barrier. A common high-side power supply (VDD1) for all three AMC1350-Q1 devices is generated from the low-side supply (VDD2) of the system by an isolated DC/DC converter circuit. A low-cost solution is based on the push-pull driver SN6501-Q1 and a transformer that supports the desired isolation voltage ratings.

The high-impedance input, high input voltage range, and the high common-mode transient immunity (CMTI) of the AMC1350-Q1 ensure reliable and accurate operation even in high-noise environments.

Figure 8-1 Using the AMC1350-Q1 for AC Line-Voltage Sensing in an OBC Application