SLVSGZ9A February   2025  – May 2025 TPS4141-Q1

ADVANCE INFORMATION  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
    1. 4.1 Pin Functions TPS4141-Q1
  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 Power Ratings
    6. 5.6 Electrical Characteristics
    7. 5.7 Switching Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Uni-directional Voltage Sensing
      2. 6.3.2 Bi-directional Voltage Sensing
      3. 6.3.3 Bi-directional and Uni-directional Voltage Sensing
      4. 6.3.4 High Voltage Input Range
      5. 6.3.5 Calculating the Output Voltage (VAOUT)
    4. 6.4 Device Functional Modes
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Divider Ratio Selection
        2. 7.2.2.2 Error Estimation
      3. 7.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Receiving Notification of Documentation Updates
    2. 8.2 Support Resources
    3. 8.3 Trademarks
    4. 8.4 Electrostatic Discharge Caution
    5. 8.5 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information
    1. 10.1 Tape and Reel Information

6.3.5 Calculating the Output Voltage (VAOUT)

The TPS4141-Q1 measures the voltage on HV (VHV) relative to the voltage on REF (VREF). For bi-directional operation, REF is set to a positive voltage relative to HVGND in the application. The resulting voltage on AOUT (VAOUT) swings above and below VREF for positive and negative VHV, respectively. For uni-directional operation, VREF = VHVGND = 0V or is connected internally to HVGND automatically based on the DIV0 and DIV1 selections. Only positive VHV voltages can be measured and resulting VAOUT is positive with respect to HVGND.

Figure 6-6 shows the transfer function of the TPS4141-Q1 in uni-directional and bi-directional modes. Gain error causes an increase or decrease in the slope of the ideal transfer function curves.

Figure 6-7 shows the transfer function zoomed in of the TPS4141-Q1 in uni-directional and bi-directional modes. Offset error causes a shift up or down of the ideal transfer curves.

TPS4141-Q1 Transfer Function and Gain Error Figure 6-6 Transfer Function and Gain Error
TPS4141-Q1 Transfer Function and Offset Error Figure 6-7 Transfer Function and Offset Error

There are several error sources that contribute to the overall measurement error of the system. These include, but are not limited, to the following:

  • TPS4141-Q1 HV input offset error, VOFFSET_HV.
  • TPS4141-Q1 HV gain error percentage, GAINERROR.
  • Reference absolute accuracy percentage, REFACC.

Assuming no error sources, Equation 1 can be used to estimate the AOUT voltage (VAOUT_IDEAL):

Equation 1. V A O U T _ I D E A L = V H V - V R E F D I V N O M + V R E F

When including the above listed error sources, Equation 2 can be used to estimate the AOUT voltage (VAOUT) for VREF, VHV, and DIVNOM values of interest:

Equation 2. V A O U T = 1 ± G A I N E R R O R 100 D I V N O M × ( V H V ± V O F F S E T _ H V ) - V R E F × 1 ± R E F A C C 100 + V R E F × 1 ± R E F A C C 100

Assuming no reference error, (REFACC = 0), Equation 2 reduces to Equation 3:

Equation 3. V A O U T = 1 ± G A I N E R R O R 100 D I V N O M × ( V H V - V R E F ± V O F F S E T _ H V )   + V R E F

Re-arranging Equation 3, VHV can be computed for a given VAOUT using Equation 4:

Equation 4. V H V = V A O U T - V R E F 1 ± G A I N E R R O R 100 × D I V N O M + V R E F ± V O F F S E T _ H V

The relative percentage error to the ideal transfer curve, %ERRORREL, for a given VREF can be found using Equation 5:

Equation 5. % E R R O R R E L = 100 % × V A O U T - V R E F V A O U T _ I D E A L - V R E F - 1

Using Equation 3 and Equation 1, %ERRORREL results in Equation 6:

Equation 6. % E R R O R R E L = ± 100 % × 1 + | G A I N E R R O R | 100 × 1 + | V O F F S E T H V | V H V - V R E F - 1