SBAS655F September   2014  – January 2020 AMC1304L05 , AMC1304L25 , AMC1304M05 , AMC1304M25

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 7 Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings
    3. 7.3  Recommended Operating Conditions
    4. 7.4  Thermal Information
    5. 7.5  Power Ratings
    6. 7.6  Insulation Specifications
    7. 7.7  Safety-Related Certifications
    8. 7.8  Safety Limiting Values
    9. 7.9  Electrical Characteristics: AMC1304x05
    10. 7.10 Electrical Characteristics: AMC1304x25
    11. 7.11 Switching Characteristics
    12. 7.12 Insulation Characteristics Curves
    13. 7.13 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Analog Input
      2. 8.3.2 Modulator
      3. 8.3.3 Digital Output
    4. 8.4 Device Functional Modes
      1. 8.4.1 Fail-Safe Output
      2. 8.4.2 Output Behavior in Case of a Full-Scale Input
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Digital Filter Usage
    2. 9.2 Typical Applications
      1. 9.2.1 Frequency Inverter Application
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
        3. 9.2.1.3 Application Curve
      2. 9.2.2 Isolated Voltage Sensing
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
        3. 9.2.2.3 Application Curve
      3. 9.2.3 What To Do and What Not To Do
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Examples
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Device Nomenclature
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Related Links
    4. 12.4 Receiving Notification of Documentation Updates
    5. 12.5 Community Resources
    6. 12.6 Trademarks
    7. 12.7 Electrostatic Discharge Caution
    8. 12.8 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9.2.2.2 Detailed Design Procedure

As indicated in Figure 56, the output of the integrated differential amplifier is internally biased to a common-mode voltage of 2 V. This voltage results in a bias current IIB through the resistive network R4 and R5 (or R4' and R5') used for setting the gain of the amplifier. The value range of this current is specified in the Electrical Characteristics table. This bias current generates additional offset error that depends on the value of the resistor R3. Because the value of this bias current depends on the actual common-mode amplitude of the input signal (as illustrated in Figure 57), the initial system offset calibration does not minimize its effect. Therefore, in systems with high accuracy requirements, TI recommends using a series resistor at the negative input (AINN) of the AMC1304 with a value equal to the shunt resistor R3 (that is, R3' = R3 in Figure 56) to eliminate the affect of the bias current.

This additional series resistor (R3') influences the gain error of the circuit. The effect can be calculated using Equation 5 with R5 = R5' = 50 kΩ and R4 = R4' = 2.5 kΩ (for the AMC1304x05) or 12.5 kΩ (for the AMC1304x25).

Equation 5. AMC1304L05 AMC1304L25 AMC1304M05 AMC1304M25 ai_equation5_bas654.gif