SBOSAF6 June   2024 TMCS1127

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison
  6. 5 Pin Configuration and Functions
  7. 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 Insulation Specifications
    6. 6.6 Electrical Characteristics
    7. 6.7 Typical Characteristics
  8. 7 Parameter Measurement Information
    1. 7.1 Accuracy Parameters
      1. 7.1.1 Sensitivity Error
      2. 7.1.2 Offset Error and Offset Error Drift
      3. 7.1.3 Nonlinearity Error
      4. 7.1.4 Power Supply Rejection Ratio
      5. 7.1.5 Common-Mode Rejection Ratio
      6. 7.1.6 External Magnetic Field Errors
    2. 7.2 Transient Response Parameters
      1. 7.2.1 CMTI, Common-Mode Transient Immunity
    3. 7.3 Safe Operating Area
      1. 7.3.1 Continuous DC or Sinusoidal AC Current
      2. 7.3.2 Repetitive Pulsed Current SOA
      3. 7.3.3 Single Event Current Capability
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Current Input
      2. 8.3.2 Ambient Field Rejection
      3. 8.3.3 High-Precision Signal Chain
        1. 8.3.3.1 Temperature Stability
        2. 8.3.3.2 Lifetime and Environmental Stability
      4. 8.3.4 Internal Reference Voltage
      5. 8.3.5 Current-Sensing Measurable Ranges
    4. 8.4 Device Functional Modes
      1. 8.4.1 Power-Down Behavior
  10. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Total Error Calculation Examples
        1. 9.1.1.1 Room-Temperature Error Calculations
        2. 9.1.1.2 Full-Temperature Range Error Calculations
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curve
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Device Nomenclature
    2. 10.2 Device Support
      1. 10.2.1 Development Support
    3. 10.3 Documentation Support
      1. 10.3.1 Related Documentation
    4. 10.4 Receiving Notification of Documentation Updates
    5. 10.5 Support Resources
    6. 10.6 Trademarks
    7. 10.7 Electrostatic Discharge Caution
    8. 10.8 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

7.1.2 Offset Error and Offset Error Drift

Offset error is the deviation from the ideal output with zero input current and most often limits measurement accuracy at low input current levels. Offset error can be referred to the output as offset voltage error or referred to the input as offset current error. When divided by device sensitivity, S, output voltage offset error VOE is input referred as input current offset error IOS (see Equation 4). Offset error referred to the input (RTI) allows for more direct comparisons or offset error with input current. Regardless of whether offset error is referred to the input as current offset error IOS, or to the output as voltage offset error VOE, offset error is a single error source and must only be included once in either input-referred or output-referred error calculations.

Equation 4. IOS=VOES

As shown in Figure 7-1, the output voltage offset error VOE of the TMCS1127 is the difference between the zero current output voltage VOUT,0A and the zero current output reference voltage VREF (see Equation 5).

Equation 5. VOE=VOUT,0A-VREF

The output offset error VOE includes magnetic offset error in the Hall sensor, offset voltage error in the signal chain, and offset error in the internal zero current output reference voltage VREF.

Offset drift is the change in the offset as a function of temperature T. Output offset drift is reported in µV/°C. To calculate offset error at any given temperature, multiply the offset drift by the change in temperature and add that value to the offset error at 25°C (see Equation 6).

Equation 6. V O E , ∆ T = V O E , 25 ℃ + V O E , d r i f t × ∆ T

where

  • VOE,drift is the output voltage offset drift with temperature in µV/°C.
  • ΔT is the change in device temperature from 25°C.