SNVSCP5A April   2025  – August 2025 TPS7H3024-SP

PRODMIX  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  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 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Quality Conformance Inspection
    8. 6.8 Typical Characteristics
  8. 7 Parameter Measurement Information
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Input Voltage (IN), VLDO and REFCAP
        1. 8.3.1.1 Undervoltage Lockout (VPOR_IN < VIN < UVLO)
        2. 8.3.1.2 Power-On Reset (VIN < VPOR_IN )
      2. 8.3.2 SR_UVLO
      3. 8.3.3 SENSEx Inputs
        1. 8.3.3.1 VTH_SENSEX and VOUTx_RISE
        2. 8.3.3.2 IHYS_SENSEx and VOUTx_FALL
        3. 8.3.3.3 Input to Output Time Diagrams
        4. 8.3.3.4 Top and Bottom Resistive Divider Design Equations
      4. 8.3.4 MODE
      5. 8.3.5 Output Stages (RESETx, PWRGD, WDO, PULL_UP1 and PULL_UP2)
        1. 8.3.5.1 Push-Pull Outputs
      6. 8.3.6 WDI
      7. 8.3.7 User-Programmable TIMERS
        1. 8.3.7.1 DLY_TMR
        2. 8.3.7.2 WD_TMR
    4. 8.4 Device Functional Modes
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Window Voltage Monitoring
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Input Power Supplies and Decoupling Capacitors
          2. 9.2.1.2.2 SR_UVLO Threshold
          3. 9.2.1.2.3 SENSEx Thresholds
        3. 9.2.1.3 Application Curves
    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 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

8.3.3.2 IHYS_SENSEx and VOUTx_FALL

The TPS7H3024 has a built-in hysteresis current of 24μA with an accuracy of ±3% (with RHYS = 49.9kΩ). The hysteresis current is approximately equivalent to VHYS/RHYS. A tolerance of 0.1% for the RHYS resistor is recommended as the tolerance ultimately affects the accuracy of the hysteresis current. This current is mirrored internally across all SENSEx inputs. This hysteresis current becomes active when the SENSEx voltage is greater than the threshold voltage (599.7mV ± 1%, refer to Equation 11 and Figure 8-3). This current (IHYS_SENSEx) multiplied by the RTOPx resistance induces a voltage (VHYS_SENSEx) that is added to the SENSEx node. This effectively boost (or increments) the node voltage (in this case VSENSEx).

When the VOUTx voltage is falling and becomes lower than VOUT_FALLx, the voltage is considered as:

  1. Not in regulation: for an undervoltage channel (UV).
  2. In regulation: for an overvoltage channel (OV).
The hysteresis voltage is defined as:
Equation 12. V H Y S _ SENSEx_N O M I N A L   ( V )   =   I H Y S _ S E N S E x × R T O P x

Where:

  • IHYS_SENSEx = 24 × 10–6 Amps (or 24μA)
  • RTOPx units are in Ohms (Ω)

The falling voltage threshold can be calculated as:

Equation 13. V OUTx_FALL _ N O M I N A L   ( V )   =   V OUTx_RISE _ N O M I N A L - V H Y S _SENSEx _ N O M I N A L

Using Equation 9 and Equation 13

Equation 14. V OUTx_FALL _ N O M I N A L   ( V ) = 1 + R T O P x R B O T T O M x × V T H _ S E N S E x -   I H Y S _ S E N S E x × R T O P x

Where:

  • VTH_SENSEx is the nominal sense threshold voltage of 0.599V
  • IHYS_SENSEx = 24 × 10–6 Amps (or 24μA)
  • RTOPx and RBOTTOMx units are in Ohms (Ω)

The VOUTx_FALL error can be calculated as:

Equation 15. V TH_FALLx _ E R R O R   ( V ) = ± A + B + C + D R B O T T O M x 2
Equation 15 was obtain, using the derivative method and under the assumptions that all variables are uncorrelated and both resistors have the same tolerance

Where the equation terms are:

Equation 16. A = I H Y S _ S E N S E x 2 × I H Y S _ S E N S E x _ A C C 2 × R T O P x 2 × R B O T T O M x 2
Equation 17. B = R T O L 2 × R T O P x 2 × V T H _ S E N S E x 2
Equation 18. C = R T O L 2 × R T O P x 2 × I H Y S _ S E N S E x × R B O T T O M x - V T H _ S E N S E x 2
Equation 19. D = V T H _ S E N S E x 2 × V T H _ S E N S E x _ A C C 2 × R T O P x + R B O T T O M x 2

Where:

  • RTOL is the resistors tolerance (same for top and bottom resistors) as numeric value. For example, for 0.1% tolerance resistors, we use 0.001.
  • VTH_SENSEx_ACC is the SENSEx threshold accuracy as numeric value (in this case 0.01).
  • IHYS_SENSEx_ACC is the hysteresis current accuracy as numeric value (in this case 0.03).
  • VTH_SENSEx is the nominal sense threshold voltage of 0.599V.
  • IHYS_SENSEx = 24 × 10–6 Amps (or 24μA).
  • RTOPx and RBOTTOMx units are in Ohms (Ω).

Using Equation 14 and Equation 15 we can calculate the falling voltage range as:

Equation 20. V OUTx_FALL = V OUTx_FALL _ N O M I N A L   ±   V OUTx_FALL _ E R R O R

Figure 8-4, shows a conceptual diagram of the rising and falling voltage, the diagram also shows the errors on this voltage due to VTH accuracy, IHYS accuracy, and the resistive divider tolerances. At the system level, these errors have to be taken into account for a robust design.

TPS7H3024-SP Rising and Falling Thresholds Voltages for the SENSEx Comparators Figure 8-4 Rising and Falling Thresholds Voltages for the SENSEx Comparators