SLUSBP5E March   2014  – July 2018 TPS92601-Q1 , TPS92602-Q1

UNLESS OTHERWISE NOTED, this document contains PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1. 3.1 Typical Schematic
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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 Electrical Characteristics
    6. 6.6 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 Fixed-Frequency PWM Control
      2. 7.3.2 Slope-Compensation Output Current
      3. 7.3.3 Boost-Current Limit
      4. 7.3.4 Oscillator and PLL
      5. 7.3.5 Control Loop Compensation
      6. 7.3.6 LED Open-Circuit Detection
      7. 7.3.7 Output Short-Circuit and Overcurrent Detection
      8. 7.3.8 Measuring LED Current During a Non-Failure Condition
      9. 7.3.9 LED Dimming Options
        1. 7.3.9.1 Analog Dimming
        2. 7.3.9.2 PWM Dimming
    4. 7.4 Device Functional Modes
      1. 7.4.1 Undervoltage and Overvoltage Shutdown
      2. 7.4.2 Overtemperature Shutdown
      3. 7.4.3 Device State Diagram
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Boost Regulator With Separate or Paralleled Channels
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1  Switching Frequency
          2. 8.2.1.2.2  Maximum Output-Current Set Point
          3. 8.2.1.2.3  Output Overvoltage-Protection Set Point
          4. 8.2.1.2.4  Duty Cycle Estimation
          5. 8.2.1.2.5  Inductor Selection
          6. 8.2.1.2.6  Rectifier Diode Selection
          7. 8.2.1.2.7  Output Capacitor Selection
          8. 8.2.1.2.8  Input Capacitor Selection
          9. 8.2.1.2.9  Current Sense and Current Limit
          10. 8.2.1.2.10 Switching MOSFET Selection
          11. 8.2.1.2.11 Loop Compensation
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Boost-to-Battery Regulator
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
          1. 8.2.2.2.1  Switching Frequency
          2. 8.2.2.2.2  Maximum Output-Current Set Point
          3. 8.2.2.2.3  Output Overvoltage-Protection Set Point
          4. 8.2.2.2.4  Duty Cycle Estimation
          5. 8.2.2.2.5  Inductor Selection
          6. 8.2.2.2.6  Rectifier Diode Selection
          7. 8.2.2.2.7  Output Capacitor Selection
          8. 8.2.2.2.8  Input Capacitor Selection
          9. 8.2.2.2.9  Current Sense and Current Limit
          10. 8.2.2.2.10 Switching MOSFET Selection
          11. 8.2.2.2.11 Loop Compensation
        3. 8.2.2.3 TPS92602y-Q1 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Related Links
    2. 11.2 Trademarks
    3. 11.3 Electrostatic Discharge Caution
    4. 11.4 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

10.1 Layout Guidelines

  • The performance of any switching regulator depends as much on the layout of the PCB as the component selection. Following a few simple guidelines maximizes noise rejection and minimizes the generation of EMI within the circuit.
  • Discontinuous currents are the most likely to generate EMI, therefore care should be taken when routing the following paths. The main path for discontinuous current in the TPS9260xy-Q1 buck regulator contains the input capacitor (CIN1), the recirculating diode (D1), the N-channel MOSFET (Q1), and the sense resistor (RLIM1). In the TPS9260xy-Q1 boost regulator, the discontinuous current flows through the output capacitor (CO1), D1, Q1, and RLIM1. In the buck-boost regulator, both loops are discontinuous and require careful attention to layout. Keep these loops as small as possible and the connections between all the components short and thick to minimize parasitic inductance. In particular, make the switch node (where L1, D1 and Q1 connect) just large enough to connect the components. To minimize excessive heating, place large copper pours adjacent to the short current path of the switch node.
  • The RT, COMP, ISNS, ICTRL, OVFB, ISP, and ISN pins are all high-impedance inputs which couple external noise easily; therefore, minimize the loops containing these nodes whenever possible. In some applications, the LED or LED array can be far away (several inches or more) from the TPS9260xy-Q1 family of devices, or on a separate PCB connected by a wiring harness. When using an output capacitor where the LED array is large or separated from the rest of the regulator, place the output capacitor close to the LEDs to reduce the effects of parasitic inductance on the ac impedance of the capacitor.
  • AGND and PGND must be separated and connected at the input GND connector.
  • The TPS9260xy-Q1 family of devices has two independent channels. in order to avoid crosstalk, the POWER GND of CH1 and CH2 must be separated and connected at the input GND connector.