SLVSC26B November   2013  – May 2024 TPS61162A , TPS61163A

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
    1.     Pin Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 EasyScale Timing Requirements
    7. 5.7 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1  Boost Converter
      2. 6.3.2  IFBx Pin Unused
      3. 6.3.3  Enable and Start-up
      4. 6.3.4  Soft Start
      5. 6.3.5  Full-Scale Current Program
      6. 6.3.6  Brightness Control
      7. 6.3.7  Undervoltage Lockout
      8. 6.3.8  Overvoltage Protection
      9. 6.3.9  Overcurrent Protection
      10. 6.3.10 Thermal Shutdown
    4. 6.4 Device Functional Modes
      1. 6.4.1 One-Wire Digital Interface (EasyScale Interface)
      2. 6.4.2 PWM Control Interface
    5. 6.5 Programming
      1. 6.5.1 EasyScale Programming
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Inductor Selection
        2. 7.2.2.2 Schottky Diode Selection
        3. 7.2.2.3 Compensation Capacitor Selection
        4. 7.2.2.4 Output Capacitor Selection
      3. 7.2.3 Application Curves
      4. 7.2.4 Additional Application Circuits
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
    2. 8.2 Related Links
    3. 8.3 Community Resources
    4. 8.4 Trademarks
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

6.4.2 PWM Control Interface

The PWM control interface is automatically enabled if the EasyScale interface fails to be enabled during startup. In this case, the TPS61162A, TPS61163A receives PWM dimming signals on the PWM pin to control the backlight brightness. When using PWM interface, the EN pin can be connected to VIN pin or a GPIO (refer to Section 7.2.4). If EN pin is connected to VIN pin, PWM pin alone is used to enable and disable the device: pulling PWM pin high or apply PWM signals at PWM pin to enable the device and pulling PWM pin low for more than 20ms to disable the device; if EN pin is connected to a GPIO, either pulling EN pin low for more than 2.5ms or pulling PWM pin low for more than 20ms can disable the device. Only after both EN and PWM signals are applied, the TPS61162A/TPS61163A can start up. Refer to Figure 6-4 for a graphical explanation.

TPS61162A TPS61163A PWM Control Interface Detection Figure 6-4 PWM Control Interface Detection

When the PWM pin is constantly high, the dual channel current is regulated to full scale according to Equation 1. The PWM pin allows PWM signals to reduce this regulation current according to the PWM duty cycle; therefore, it achieves LED brightness dimming. The relationship between the PWM duty cycle and IFBx current is given by Equation 3.

Equation 3. TPS61162A TPS61163A

where

  • IFBx is the current of each current sink
  • IFB_full is the full-scale LED current
  • Duty is the duty cycle information detected from the PWM signals