SLVSGC5B January   2023  – May 2024 TPS62870 , TPS62871 , TPS62872 , TPS62873

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Description (continued)
  6. 5 Device Options
  7. 6 Pin Configuration and Functions
  8. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings_Catalog
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 I2C Interface Timing Characteristics
    7. 7.7 Timing Requirements
    8. 7.8 Typical Characteristics
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Fixed-Frequency DCS Control Topology
      2. 8.3.2  Forced PWM and Power Save Modes
      3. 8.3.3  Precise Enable
      4. 8.3.4  Start-Up
      5. 8.3.5  Switching Frequency Selection
      6. 8.3.6  Output Voltage Setting
        1. 8.3.6.1 Output Voltage Range
        2. 8.3.6.2 Output Voltage Setpoint
        3. 8.3.6.3 Non-Default Output Voltage Setpoint
        4. 8.3.6.4 Dynamic Voltage Scaling
      7. 8.3.7  Compensation (COMP)
      8. 8.3.8  Mode Selection and Clock Synchronization (MODE/SYNC)
      9. 8.3.9  Spread Spectrum Clocking (SSC)
      10. 8.3.10 Output Discharge
      11. 8.3.11 Undervoltage Lockout (UVLO)
      12. 8.3.12 Overvoltage Lockout (OVLO)
      13. 8.3.13 Overcurrent Protection
        1. 8.3.13.1 Cycle-by-Cycle Current Limiting
        2. 8.3.13.2 Hiccup Mode
        3. 8.3.13.3 Current Limit Mode
      14. 8.3.14 Power Good (PG)
        1. 8.3.14.1 Standalone or Primary Device Behavior
        2. 8.3.14.2 Secondary Device Behavior
      15. 8.3.15 Remote Sense
      16. 8.3.16 Thermal Warning and Shutdown
      17. 8.3.17 Stacked Operation
    4. 8.4 Device Functional Modes
      1. 8.4.1 Power-On Reset
      2. 8.4.2 Undervoltage Lockout
      3. 8.4.3 Standby
      4. 8.4.4 On
    5. 8.5 Programming
      1. 8.5.1 Serial Interface Description
      2. 8.5.2 Standard, Fast, Fast Mode Plus Protocol
      3. 8.5.3 I2C Update Sequence
      4. 8.5.4 I2C Register Reset
  10. 9 Register Map
  11. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Selecting the Inductor
        2. 10.2.2.2 Selecting the Input Capacitors
        3. 10.2.2.3 Selecting the Compensation Resistor
        4. 10.2.2.4 Selecting the Output Capacitors
        5. 10.2.2.5 Selecting the Compensation Capacitor, CC
        6. 10.2.2.6 Selecting the Compensation Capacitor, CC2
      3. 10.2.3 Application Curves
    3. 10.3 Best Design Practices
    4. 10.4 Power Supply Recommendations
    5. 10.5 Layout
      1. 10.5.1 Layout Guidelines
      2. 10.5.2 Layout Example
  12. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  13. 12Revision History
  14. 13Mechanical, Packaging, and Orderable Information

8.3.6.4 Dynamic Voltage Scaling

If the user changes the output voltage setpoint while the DC/DC converter is operating, the device ramps up or down to the new voltage setting in a controlled way.

The VRAMP[1:0] bits in the CONTROL1 register sets the slew rate when the device ramps from one voltage to another during DVS (see Table 8-6).

Table 8-6 Dynamic Voltage Scaling Slew Rate
VRAMP[1:0]DVS Slew Rate
0b0010mV/μs (0.5μs/step)
0b015mV/μs (1μs/step)
0b101.25mV/μs (5μs/step)
0b110.5mV/μs (10μs/step)

Note that ramping the output to a higher voltage requires additional output current, so that during DVS, the converter must generate a total output current given by:

Equation 2. TPS62870 TPS62871 TPS62872 TPS62873

where

  • IOUT is the total current the converter must generate while ramping to a higher voltage.
  • IOUT(DC) is the DC load current.
  • COUT is the total output capacitance.
  • dVOUT/dt is the slew rate of the output voltage (programmable in the range 0.5mV/µs to 10mV/µs).

For correct operation, make sure that the total output current during DVS does not exceed the current limit of the device.