SLVS996D September   2009  – September 2015 TPS54262-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 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 DC Electrical Characteristics
    6. 6.6 DC Electrical Characteristics
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Unregulated Input Voltage
      2. 7.3.2  Regulated Output Voltage
      3. 7.3.3  Regulation and Feedback Voltage
      4. 7.3.4  Enable and Shutdown
      5. 7.3.5  Soft Start
      6. 7.3.6  Oscillator Frequency
        1. 7.3.6.1 Selecting the Switching Frequency
        2. 7.3.6.2 Synchronization With External Clock
      7. 7.3.7  Slew Rate Control
      8. 7.3.8  Reset
      9. 7.3.9  Reset Delay
      10. 7.3.10 Reset Threshold and Undervoltage Threshold
      11. 7.3.11 Overvoltage Supervisor
      12. 7.3.12 Noise Filter on RST_TH and OV_TH Terminals
      13. 7.3.13 Boot Capacitor
      14. 7.3.14 Short Circuit Protection
      15. 7.3.15 Overcurrent Protection
      16. 7.3.16 Internal Undervoltage Lockout (UVLO)
      17. 7.3.17 Thermal Shutdown (TSD)
      18. 7.3.18 Loop Control Frequency Compensation - Type 3
        1. 7.3.18.1 Bode Plot of Converter Gain
    4. 7.4 Device Functional Modes
      1. 7.4.1 Active Mode Continuous Conduction Mode (CCM)
      2. 7.4.2 Active Mode Discontinuous Conduction Mode (DCM)
      3. 7.4.3 Pulse Skip Mode (PSM)
      4. 7.4.4 Low-Power Mode (LPM)
      5. 7.4.5 Hysteretic Mode
      6. 7.4.6 Output Tolerances in Different Modes of Operation
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Component Selection
          1. 8.2.2.1.1  Input Capacitors (C1, C11)
          2. 8.2.2.1.2  Output Capacitor (C4, C12)
          3. 8.2.2.1.3  Soft-Start Capacitor (C6)
          4. 8.2.2.1.4  Bootstrap Capacitor (C3)
          5. 8.2.2.1.5  Power-On Reset Delay (PORdly) Capacitor (C2)
          6. 8.2.2.1.6  Output Inductor (L1)
          7. 8.2.2.1.7  Flyback Schottky Diode (D2)
          8. 8.2.2.1.8  Resistor to Set Slew Rate (R7)
          9. 8.2.2.1.9  Resistor to Select Switching Frequency (R8)
          10. 8.2.2.1.10 Resistors to Select Output Voltage (R4, R5)
          11. 8.2.2.1.11 Resistors to Set Undervoltage, Overvoltage, and Reset Thresholds (R1, R2, R3)
            1. 8.2.2.1.11.1 Overvoltage Resistor Selection
            2. 8.2.2.1.11.2 Reset Threshold Resistor Selection
            3. 8.2.2.1.11.3 Undervoltage Threshold for Low-Power Mode and Load Transient Operation
          12. 8.2.2.1.12 Low-Power Mode (LPM) Threshold
          13. 8.2.2.1.13 Enable Pin Pull-Up Resistor (R11) and Voltage Divider Resistor (R10)
          14. 8.2.2.1.14 Pull-Up Resistor (R12) at RST Pin
          15. 8.2.2.1.15 Type 3 Compensation Components (R5, R6, R9, C5, C7, C8)
            1. 8.2.2.1.15.1 Resistors
            2. 8.2.2.1.15.2 Capacitors
          16. 8.2.2.1.16 Noise Filter on RST_TH and OV_TH Terminals (C9, C10)
        2. 8.2.2.2 Design Example 1
          1. 8.2.2.2.1  Calculate the Switching Frequency (fsw)
          2. 8.2.2.2.2  Calculate the Ripple Current (IRipple)
          3. 8.2.2.2.3  Calculate the Inductor Value (L1)
          4. 8.2.2.2.4  Calculate the Output Capacitor and ESR (C4)
            1. 8.2.2.2.4.1 Calculate capacitance
            2. 8.2.2.2.4.2 Calculate ESR
          5. 8.2.2.2.5  Calculate the Feedback Resistors (R4, R5)
          6. 8.2.2.2.6  Calculate Type 3 Compensation Components
            1. 8.2.2.2.6.1 Resistances (R6, R9)
            2. 8.2.2.2.6.2 Capacitors (C5, C8, C7)
          7. 8.2.2.2.7  Calculate Soft-Start Capacitor (C6)
          8. 8.2.2.2.8  Calculate Bootstrap Capacitor (C3)
          9. 8.2.2.2.9  Calculate Power-On Reset Delay Capacitor (C2)
          10. 8.2.2.2.10 Calculate Input Capacitor (C1, C11)
          11. 8.2.2.2.11 Calculate Resistors to Control Slew Rate (R7)
          12. 8.2.2.2.12 Resistors to Select Undervoltage, Overvoltage and Reset Threshold Values (R1, R2, R3)
          13. 8.2.2.2.13 Diode D1 and D2 Selection
          14. 8.2.2.2.14 Noise Filter on RST_TH and OV_TH Terminals (C9 and C10)
          15. 8.2.2.2.15 Power Budget and Temperature Estimation
        3. 8.2.2.3 Design Example 2
          1. 8.2.2.3.1  Calculate the Switching Frequency (fsw)
          2. 8.2.2.3.2  Calculate the Ripple Current (IRipple)
          3. 8.2.2.3.3  Calculate the Inductor Value (L1)
          4. 8.2.2.3.4  Calculate the Output Capacitor and ESR (C4, C12)
            1. 8.2.2.3.4.1 Calculate Capacitance
            2. 8.2.2.3.4.2 Calculate ESR
          5. 8.2.2.3.5  Calculate the Feedback Resistors (R4, R5)
          6. 8.2.2.3.6  Calculate Type 3 Compensation Components
            1. 8.2.2.3.6.1 Resistances (R6, R9)
            2. 8.2.2.3.6.2 Capacitors (C5, C8, C7)
          7. 8.2.2.3.7  Calculate Soft-Start Capacitor (C6)
          8. 8.2.2.3.8  Calculate Bootstrap Capacitor (C3)
          9. 8.2.2.3.9  Calculate Power-On Reset Delay Capacitor (C2)
          10. 8.2.2.3.10 Calculate Input Capacitor (C1, C11)
          11. 8.2.2.3.11 Calculate Resistors to Control Slew Rate (R7)
          12. 8.2.2.3.12 Resistors to Select Undervoltage, Overvoltage and Reset Threshold Values (R1, R2, R3)
          13. 8.2.2.3.13 Diode D1 and D2 Selection
          14. 8.2.2.3.14 Noise Filter on RST_TH and OV_TH Terminals (C9 and C10)
          15. 8.2.2.3.15 Power Budget and Temperature Estimation
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Power Dissipation and Temperature Considerations
  11. 11Device and Documentation Support
    1. 11.1 Community Resource
    2. 11.2 Trademarks
    3. 11.3 Electrostatic Discharge Caution
    4. 11.4 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

9 Power Supply Recommendations

The design of the TPS54262-Q1 devices is for operation using an input supply range from 3.6 V to 48 V. Both the VIN input pins must be shorted together at the board level. One high frequency filter capacitor in the range from 0.1 uF to 0.01 uF is recommended at VIN pin. Additionally, to minimize the ripple voltage, use a ceramic bulk capacitor of type X5R or X7R at the VIN pin. See Equation 25 and Equation 26 for calculating the value of this bulk capacitor. If there is a possibility for a reverse-voltage condition to occur, place a series Schottky diode in the power routing.