SLPS785 December   2023 RES11A

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. 6 Parameter Measurement Information
    1. 6.1 DC Measurement Configurations
    2. 6.2 AC Measurement Configurations
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Ratiometric Matching
      2. 7.3.2 Ratiometric Drift
      3. 7.3.3 Predictable Voltage Coefficient
      4. 7.3.4 Ultra-Low Noise
    4. 7.4 Device Functional Modes
  9. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Discrete Difference Amplifier
        1. 8.1.1.1 Difference-Amplifier Common-Mode Rejection Analysis
      2. 8.1.2 Discrete Instrumentation Amplifiers
        1. 8.1.2.1 Instrumentation Amplifier Common-Mode Rejection Analysis
      3. 8.1.3 Fully Differential Amplifier
    2. 8.2 Typical Application
      1. 8.2.1 Common-Mode Shifting Input Stage
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Examples
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Development Support
        1. 9.1.1.1 PSpice® for TI
        2. 9.1.1.2 TINA-TI™ Simulation Software (Free Download)
        3. 9.1.1.3 TI Reference Designs
        4. 9.1.1.4 Filter Design Tool
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information
    1. 11.1 Tape and Reel Information
    2. 11.2 Mechanical Data

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • DDF|8
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.3.3 Predictable Voltage Coefficient

The voltage coefficients of the RES11A are almost entirely related to self-heating, where the power dissipated in the device raises the die temperature. As previously mentioned, the commonality of this temperature rise leads to a comparable shift in each resistor, such that the divider ratio is well preserved.

Applying voltage V across resistor or divider R results in the loss of a corresponding power dissipation of P = V2 / R, in the form of heat in the device die. This heat leads to a localized increase in the junction temperature, which in turn causes the same parametric shifts previously discussed in the context of temperature coefficients. TCR is specified as a function of ambient temperature; therefore, use the effective junction-to-ambient thermal resistance to determine the effective temperature rise and calculate the nominal or expected shift.

Equation 9. R expected = V R 2 R × R θJA effective × TCR abs × R
GUID-20231215-SS0I-2CR8-CDLP-DLLQBDKNZ9W1-low.svgFigure 7-1 RIN Resistance vs Voltage
GUID-20231215-SS0I-DLPT-4KLM-K2VSMC1CBRGS-low.svgFigure 7-2 RG Resistance vs Voltage

The difference of the expected value of R from the actual value of R describes the actual-to-expected mismatch error of R, due to non-temperature-related effects on the voltage coefficient. Similar to the logarithmic conformity error of a logarithmic amplifier or the integrated nonlinearity error of an ADC, this error describes the deviations of the actual device behavior from the predictable behavior. While the absolute magnitude of the shift varies, the slope or trend is predictable.

GUID-20231213-SS0I-8BFW-DQB4-V0VJNPLRFDJB-low.svg Figure 7-3 Resistor Actual-to-expected Mismatch vs Voltage

The measured value of R for low bias (measured by sourcing a very small current) is used with the actual value of R to calculate the effective voltage coefficient of resistance.

Equation 10. Voltage coefficient (Ω/V) = R biased – R initial V bias

This exercise is repeated for each Rx, tD1, tD2, and tM, to calculate the voltage coefficients associated with each parameter. For example, the RES11A40 has a typical absolute voltage coefficient of approximately 0.02 Ω/V for RIN or RG. When considered in ratiometric terms, the typical voltage coefficient of tD1 or tD2 is 2 ppm/V, and the voltage coefficient of tM is 0.5 ppm/V.