SBASB13 December   2024 AMC0311S

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Device Comparison Table
  6. Pin Configuration and Functions
  7. Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information (D Package)
    5. 6.5  Thermal Information (DWV Package)
    6. 6.6  Power Ratings 
    7. 6.7  Insulation Specifications (Basic Isolation)
    8. 6.8  Insulation Specifications (Reinforced Isolation)
    9. 6.9  Safety-Related Certifications (Basic Isolation)
    10. 6.10 Safety-Related Certifications (Reinforced Isolation)
    11. 6.11 Safety Limiting Values (D Package)
    12. 6.12 Safety Limiting Values (DWV Package)
    13. 6.13 Electrical Characteristics
    14. 6.14 Switching Characteristics
    15. 6.15 Timing Diagram
    16. 6.16 Insulation Characteristics Curves
    17. 6.17 Typical Characteristics
  8. 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 Reference Input
    5. 7.5 Device Functional Modes
  9. 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 Connecting the REFIN pin
      3. 8.2.3 Application Curve
    3. 8.3 Best Design Practices
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
  10. Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Input Filter Design

Place a RC filter in front of the device to improve signal-to-noise performance of the signal path. Input noise with a frequency close to the ΔΣ modulator sampling frequency (typically 10MHz) is folded back into the low-frequency range by the modulator. The purpose of the RC filter is to attenuate high-frequency noise below the desired noise level of the measurement. In practice, a cutoff frequency that is two orders of magnitude lower than the modulator frequency yields good results.

Most voltage-sensing applications use high-impedance resistive dividers in front of the isolated modulator to scale down the input voltage. In this case, a single capacitor, as shown in Figure 8-2, is sufficient to filter the input signal. For (R1 + R2) >> RSNS, the cut-off frequency of the input filter is 1 / (2 x π x RSNS x C5). For example, RSNS =10kΩ and C5 = 100pF results in a cutoff frequency of 160kHz.

AMC0311S AMC0211S Input Filter Figure 8-2 Input Filter