SNVSCV5 October   2025 TPS923621 , TPS923622

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  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 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Enable and Start-up
      2. 7.3.2 Under-Voltage Lockout (UVLO)
      3. 7.3.3 Shutdown
      4. 7.3.4 Boost Control Operation
      5. 7.3.5 Switching Peak Current Limit
      6. 7.3.6 Over-Voltage Protection
      7. 7.3.7 Output Current Setting
      8. 7.3.8 Output Current PWM Controlled Analog Dimming
      9. 7.3.9 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Normal Operation Mode
      2. 7.4.2 Over-Voltage Protection Mode
      3. 7.4.3 Shutdown Mode
  9. 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 Inductor Selection
        2. 8.2.2.2 Schottky Diode Selection
        3. 8.2.2.3 Output Capacitor Selection
        4. 8.2.2.4 LED Current Set Resistor
        5. 8.2.2.5 Thermal Considerations
      3. 8.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

7.1 Overview

The TPS923621/2 is a high-current, high-efficiency, high-output-voltage fully-integrated synchronous boost converter in small package size. The device integrates 280mΩ low-side switch FET and 600mΩ high-side switch FET and is designed for output voltage up to 30V with a switch peak current limit of 2.25A. Its large driving capability can drive single or parallel LED strings for small to large size LCD panel back lighting or general illumination.

The TPS923621/2 operates in peak current mode (PCM) control with quasi-constant frequency. It is internally compensated for maximum flexibility and stability, which also enables a simple design. During the low-side switch FET on-time, the inductor current rises until reaching a threshold value set by the internal GM amplifier. Then, the low-side switch FET is turned off and the high-side switch FET is turned on which lets the current flow towards the output of the boost converter. The adaptive off-time varies as a function of VIN and VOUT, to maintain a nearly constant frequency, which provides better stability for the system over a wider range of input voltage and output voltage than conventional boost converters. The TPS923621/2 topology also has the benefits of providing very good load and line regulations, and excellent line and load transient responses.

The TPS923621/2 implements PWM controlled analog dimming by changing feedback (FB) voltage proportional to the duty cycle of PWM input signal in 0.1% to 100% range. The feedback loop regulates the FB pin to a reference voltage of 200mV for 100% PWM duty cycle, reducing the power dissipation in the current sense resistor.

The TPS923621/2 is optimized for single-cell lithium-ion battery applications, featuring an ultra-low 130nA shutdown current that extends battery life. It can support 2.5V low VIN when battery near full discharge. The TPS923621/2 has both 1.1MHz version and 400KHz version switch frequency options. The 1.1MHz version supports ultra-compact surface-mount inductors and capacitors, while the 400KHz version is ideal for applications with EMI constraints near the 1.1MHz frequency band.