TIDUF26 june   2023 BQ24072 , LMR36520 , TLV62568 , TPS2116

 

  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 24 VAC to DC Rectification
      2. 2.2.2 eFuse Protection
      3. 2.2.3 5-V Rails
        1. 2.2.3.1 LMR36520 Voltage Rail
        2. 2.2.3.2 USB Power Input
      4. 2.2.4 Power Source ORing
      5. 2.2.5 Battery Management
      6. 2.2.6 3.3-V Power Rail
      7. 2.2.7 Power Rail Current Sensing
      8. 2.2.8 Backlight LED Driver
      9. 2.2.9 BoosterPack Overview
    3. 2.3 Highlighted Products
      1. 2.3.1 LMR36520
      2. 2.3.2 TPS2116
      3. 2.3.3 TLV62568
      4. 2.3.4 INA2180
      5. 2.3.5 TPS92360
      6. 2.3.6 TPS2640
      7. 2.3.7 BQ24072
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
    2. 3.2 Test Setup
    3. 3.3 Test Results
      1. 3.3.1  24-VAC Start-Up and Shutdown
      2. 3.3.2  USB Start-Up and Shutdown
      3. 3.3.3  ORing
      4. 3.3.4  LMR36520
      5. 3.3.5  TLV62568 Transient Response
      6. 3.3.6  BM24072 Transient Response
      7. 3.3.7  TLV62568 (3V3 Power Rail)
      8. 3.3.8  LMR36520 (LMOut Power Rail)
      9. 3.3.9  BM24072 (BMOut Power Rail)
      10. 3.3.10 Reference
        1. 3.3.10.1 TLV62568
        2. 3.3.10.2 LMR36520
  10. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
    2. 4.2 Tools and Software
    3. 4.3 Documentation Support
    4. 4.4 Support Resources
    5. 4.5 Trademarks
  11. 5About the Author

3.3.8 LMR36520 (LMOut Power Rail)

The LMR36520 produces a larger ripple when operating in DCM when compared to CCM. Regardless of the mode, the LMR36520 produces an output ripple of less than 1% across the entire load range. Jitter on the switch node as shown in Figure 3-41 is expected as the rectified 24 VAC exhibits significant ripple that the LMR36520 is constantly adjusting for. The amount of ripple exhibited on the rectified 24 VAC increases with higher load currents thereby increasing jitter on the LMR36520 switch node.

GUID-20230607-SS0I-L7TG-HQRR-B5WTDMV2B09J-low.png Figure 3-41 LMROut Ripple (No Load)
GUID-20230607-SS0I-CJ5S-3NN7-GXTCLTFDMMDC-low.png Figure 3-42 LMROut Ripple (150-mA Load)
GUID-20230607-SS0I-MVGK-ZTDN-5DDCP5L02NF3-low.png Figure 3-43 LMROut Ripple (300-mA Load)
GUID-20230607-SS0I-1QXN-1WCG-WHW6BGQ2XRKV-low.png Figure 3-44 LMROut Ripple Persist (300-mA Load)
GUID-20230607-SS0I-HXP9-LPTR-VLWZLRXZN9JJ-low.png Figure 3-45 LMROut Ripple (490-mA Load)
GUID-20230607-SS0I-BRRB-S1WD-VMZXJZZKQVW5-low.png Figure 3-46 Needs Title