SLVSGG8B November   2023  – August 2024 TPS6287B10 , TPS6287B15 , TPS6287B20 , TPS6287B25

PRODMIX  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Options
  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 I2C Interface Timing Characteristics
    7. 6.7 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  Fixed-Frequency DCS-Control Topology
      2. 8.3.2  Forced-PWM and Power-Save Modes
      3. 8.3.3  Transient Non-Synchronous Mode (optional)
      4. 8.3.4  Precise Enable
      5. 8.3.5  Start-Up
      6. 8.3.6  Switching Frequency Selection, Only Applies to TPS6287BxxJE2
      7. 8.3.7  Output Voltage Setting
        1. 8.3.7.1 Output Voltage Range
        2. 8.3.7.2 Output Voltage Setpoint
        3. 8.3.7.3 Non-Default Output Voltage Setpoint
        4. 8.3.7.4 Dynamic Voltage Scaling
        5. 8.3.7.5 Droop Compensation
      8. 8.3.8  Compensation (COMP)
      9. 8.3.9  Mode Selection / Clock Synchronization (MODE/SYNC)
      10. 8.3.10 Spread Spectrum Clocking (SSC)
      11. 8.3.11 Output Discharge
      12. 8.3.12 Undervoltage Lockout (UVLO)
      13. 8.3.13 Overvoltage Lockout (OVLO)
      14. 8.3.14 Overcurrent Protection
        1. 8.3.14.1 Cycle-by-Cycle Current Limiting
        2. 8.3.14.2 Hiccup Mode
        3. 8.3.14.3 Current-Limit Mode
      15. 8.3.15 Power Good (PG)
        1. 8.3.15.1 Standalone / Primary Device Behavior
        2. 8.3.15.2 Secondary Device Behavior
      16. 8.3.16 Remote Sense
      17. 8.3.17 Thermal Warning and Shutdown
      18. 8.3.18 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 HS-Mode Protocol
      4. 8.5.4 I2C Update Sequence
      5. 8.5.5 I2C Register Reset
      6. 8.5.6 Dynamic Voltage Scaling (DVS)
  10. 9 Device Registers
  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 Inductor Selection
        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 Typical Application - TPS6287BxV Devices
      1. 10.3.1 Design Requirements for TPS6287BxV
    4. 10.4 Typical Application Using Two TPS6287B25 in a Stacked Configuration
      1. 10.4.1 Design Requirements For Two Stacked Devices
      2. 10.4.2 Detailed Design Procedure
        1. 10.4.2.1 Selecting the Compensation Resistor
        2. 10.4.2.2 Selecting the Output Capacitors
        3. 10.4.2.3 Selecting the Compensation Capacitor CC
      3. 10.4.3 Application Curves for Two Stacked Devices
    5. 10.5 Typical Application Using Three TPS6287B25 in a Stacked Configuration
      1. 10.5.1 Application Curves
    6. 10.6 Power Supply Recommendations
    7. 10.7 Layout
      1. 10.7.1 Layout Guidelines
      2. 10.7.2 Layout Example
  12. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    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

Package Options

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

8.3.6 Switching Frequency Selection, Only Applies to TPS6287BxxJE2

During device initialization, a resistor-to-digital converter in the device determines the state of the FSET pin and sets the switching frequency of the DC/DC converter according to Table 8-2.

Table 8-2 Switching Frequency Options
Resistor at FSET (1%) Switching Frequency
6.2 kΩ to GND 1.5 MHz
Short to GND 2.25 MHz
Short to VIN 2.5 MHz
47 kΩ to VIN 3 MHz

The following figure shows a simplified block diagram of the R2D converter used to detect the state of the FSET pin (an identical circuit detects the state of the VSET pin – see Output Voltage Setpoint).

TPS6287B10 TPS6287B15 TPS6287B20 TPS6287B25 FSET R2D Converter Functional Block Diagram Figure 8-10 FSET R2D Converter Functional Block Diagram
Detection of the state of the FSET pin works as follows:

To detect the most significant bit (MSB), the circuit opens S1 and S2, and the input buffer detects if a high or a low level is connected to the FSET pin.

To detect the least significant bit (LSB):

  • If the MSB is 0, the circuit closes S1. If the input buffer detects a high level, the LSB = 1; if the circuit detects a low level, the LSB = 0.
  • If the MSB is 1, the circuit closes S2. If the input buffer detects a low level, the LSB = 0; if the circuit detects a high level, the LSB = 1.

The propagation delay of the current-sensing comparator limits the minimum on-time of the device. In practice, this means that the maximum switching frequency the device can support decreases with small duty cycles. Figure 6-5 shows the practical operating range of the device with 3.3-V and 5-V supplies.