TIDUEZ4 May   2021

 

  1.   Description
  2.   Resources
  3.   Features
  4.   Applications
  5.   5
  6. 1System Description
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Highlighted Products
      1. 2.2.1 SimpleLink MCU
        1. 2.2.1.1 CC3235MODS
        2. 2.2.1.2 CC1352R LaunchPad
          1. 2.2.1.2.1 CC1352R
      2. 2.2.2 Power
        1. 2.2.2.1 TPS63802
        2. 2.2.2.2 TPS63900
        3. 2.2.2.3 TPS62825
        4. 2.2.2.4 TPS7A03
        5. 2.2.2.5 TPS7A20
        6. 2.2.2.6 TPS62840
        7. 2.2.2.7 TPS22919
        8. 2.2.2.8 LM66100
      3. 2.2.3 Peripherals
        1. 2.2.3.1 OPT3004
        2. 2.2.3.2 DRV8837C
        3. 2.2.3.3 TPA2011
        4. 2.2.3.4 TLV61048
      4. 2.2.4 OmniVision Video Encoder OA7000
      5. 2.2.5 OmniVision Image Sensor SP2329
      6. 2.2.6 YTOT Lens Module
    3. 2.3 Design Considerations
      1. 2.3.1  Input Power: Battery and USB
      2. 2.3.2  Power Requirements
      3. 2.3.3  Camera Wake-up and Day or Night Sensing
        1. 2.3.3.1 PIR and MSP430 Based Motion Detection Design for Low Cost and High Performance
      4. 2.3.4  Battery Gauging
      5. 2.3.5  IR LED Illumination
      6. 2.3.6  IR Cut Filter
      7. 2.3.7  Audio
      8. 2.3.8  System Operation
      9. 2.3.9  Wi-Fi and Host Subsystem
      10. 2.3.10 Firmware Control
        1. 2.3.10.1 Application Flow
  8. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware
    2. 3.2 Software
    3. 3.3 Setup
      1. 3.3.1 Configuration Steps for Video over Wi-Fi
      2. 3.3.2 (Optional) Flash OA7000 With Latest Firmware or Stream Video Over USB
      3. 3.3.3 Audio Streaming
      4. 3.3.4 LPSTK-CC1352R Configuration Steps for Camera Module
    4. 3.4 Test Results
      1. 3.4.1 Power Supply Rails and Current Consumption
      2. 3.4.2 Battery Life Calculations
      3. 3.4.3 Video Streaming
      4. 3.4.4 IR LED Drive
  9. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 Bill of Materials
    2. 4.2 Software
    3. 4.3 Support Resources
    4. 4.4 References
    5. 4.5 Trademarks
  10. 5About the Author

2.2.2.7 TPS22919

The TPS22919 device is a 5.5 V, 1.5 A load switch in a 6-pin SOT-23 package. To reduce voltage drop for low voltage and high current rails, the device implements a low resistance N-channel MOSFET which reduces the drop out voltage across the device. The TPS22919 device has a slow slew rate which helps reduce or eliminate power supply droop because of large inrush currents. Furthermore, the device features a QOD pin, which allows the configuration of the discharge rate of VOUT once the switch is disabled. During shutdown, the device has very low leakage currents, thereby reducing unnecessary leakages for downstream modules during standby. Integrated control logic, driver, charge pump, and output discharge FET eliminates the need for any external components which reduces solution size and bill of materials (BOM) count. The TPS22919 load switch is also self-protected, meaning that it will protect itself from short circuit events on the output of the device. It also has thermal shutdown to prevent any damage from overheating.

GUID-95EC9AD7-69E9-4F86-95C5-730677B73E02-low.gif Figure 2-12 TPS22919 Functional Block Diagram

In this design, TPS22919 load switch is used to reduce the shutdown current of loads (video processor, IR LED driver, sensors) that consume few µA current in deep-sleep or hibernation mode. The TPS22919 load switch reduces the shutdown current of the camera to just 10 nA that enables longer battery life.