TIDUFA5 December   2024

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Small Compact Size
      2. 2.2.2 Transformerless Design
    3. 2.3 Highlighted Products
      1. 2.3.1  BQ25790 IIC Controlled, 1–4 Cell, 5A Buck-Boost Battery Charger
      2. 2.3.2  TPS3422 Low-Power, Push-Button Controllers With Configurable Delay
      3. 2.3.3  SN74LVC1G74 Single Positive-Edge-Triggered D-Type Flip-Flop With Clear and Preset
      4. 2.3.4  TPS259470 2.7V–23V, 5.5A, 28mΩ True Reverse Current Blocking eFuse
      5. 2.3.5  TPS54218 2.95V to 6V Input, 2A Synchronous Step-Down SWIFT Converter
      6. 2.3.6  TPS54318 2.95V to 6V Input, 3A Synchronous Step-Down SWIFT Converter
      7. 2.3.7  LM5158 2.2MHz, Wide VIN, 85V Output Boost, SEPIC, or Flyback Converter
      8. 2.3.8  TPS61178 20V Fully Integrated Sync Boost With Load Disconnect
      9. 2.3.9  LMZM23601 36V, 1A Step-Down DC-DC Power Module in 3.8mm × 3mm Package
      10. 2.3.10 TPS7A39 Dual, 150mA, Wide-VIN, Positive and Negative Low-Dropout (LDO) Voltage Regulator
      11. 2.3.11 TPS74401 3.0A, Ultra-LDO With Programmable Soft Start
      12. 2.3.12 TPS7A96 2A, Ultra-Low Noise, Ultra-high PSRR RF Voltage Regulator
      13. 2.3.13 LM3880 3-Rail Simple Power Sequencer With Fixed Time Delay
      14. 2.3.14 DAC53401 10-Bit, Voltage-Output DAC With Nonvolatile Memory
      15. 2.3.15 INA231 28V, 16-bit, I2C Output Current, Voltage, and Power Monitor With Alert in WCSP
  9. 3System Design Theory
    1. 3.1 Input Section
      1. 3.1.1 Buck-Boost Charger
      2. 3.1.2 Power On or Off
    2. 3.2 Designing SEPIC and Cuk Based High-Voltage Power Supply
      1. 3.2.1 Basic Operation Principle of SEPIC and Cuk Converters
      2. 3.2.2 Dual High-Voltage Power Supply Design Using Uncoupled Inductors With SEPIC and Cuk
        1. 3.2.2.1 Duty Cycle
        2. 3.2.2.2 Inductor Selection
        3. 3.2.2.3 Power MOSFET Verification
        4. 3.2.2.4 Output Diode Selection
        5. 3.2.2.5 Coupling Capacitor Selection
        6. 3.2.2.6 Output Capacitor Selection
        7. 3.2.2.7 Input Capacitor Selection
        8. 3.2.2.8 Programming the Output Voltage With Adjustable function
    3. 3.3 Designing the Low-Voltage Power Supply
      1. 3.3.1 Designing the TPS54218 Through WEBENCH Power Designer
      2. 3.3.2 ±5V Transmit Supply Generation
    4. 3.4 System Clock Synchronization
    5. 3.5 Power and Data Output Connector
    6. 3.6 System Current and Power Monitoring
  10. 4Hardware, Testing Requirements, and Test Results
    1. 4.1 Hardware Requirements
    2. 4.2 Test Setup
    3. 4.3 Test Results
      1. 4.3.1 Efficiency Test Result
      2. 4.3.2 Line Regulation Testing Result
      3. 4.3.3 Spectrum Test Result
  11. 5Design and Documentation Support
    1. 5.1 Design Files
      1. 5.1.1 Schematics
      2. 5.1.2 BOM
      3. 5.1.3 PCB Layout Recommendations
        1. 5.1.3.1 High-Voltage Supply Layout
    2. 5.2 Tools and Software
    3. 5.3 Documentation Support
    4. 5.4 Support Resources
    5. 5.5 Trademarks

3.2.2 Dual High-Voltage Power Supply Design Using Uncoupled Inductors With SEPIC and Cuk

This section describes the implementation of the dual high-voltage supply using uncoupled inductors. The specifications of the dual supply are described in Table 1-1. Section 3.2.2.1 through Section 3.2.2.8 provide a step-by-step method to design the supply. This system can be thought of as two parallel output stages coupled through capacitors C1 and C15 with the primary side as shown in Figure 3-11. To create a high-voltage dual supply, the output stage of the high-voltage power supply (HVPS) was designed differently. As Figure 3-11 shows, the output capacitors are charged to the positive rail of 75V for the top stage (SEPIC). Similarly, the output capacitors of the bottom stage are charged to a negative supply of –75V (Cuk). This is due to the inclusion of the HVGND in Figure 3-11 between R7, R11, and R13. A dual high-voltage power supply was achieved using HVGND. Following the output of both rails, a Pi and Power Filter were used to attenuate the ripple of the high-voltage supply.

TIDA-010269 SEPIC and Cuk Converter Schematic Figure 3-11 SEPIC and Cuk Converter Schematic