TIDUFB3 July   2025

 

  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
    3. 2.3 Highlighted Products
      1. 2.3.1 TPS7H5006-SEP
      2. 2.3.2 TPS7H6025-SEP
      3. 2.3.3 TPS7H1111-SEP
      4. 2.3.4 TPS7H4010-SEP
      5. 2.3.5 TPS73801-SEP
      6. 2.3.6 TPS7H3302-SEP
      7. 2.3.7 TPS7H3014-SEP
      8. 2.3.8 TPS7H2221-SEP
      9. 2.3.9 SN54SC6T14-SEP
  9. 3System Design Theory
    1. 3.1 0V8 Discrete Buck Regulator (VCCINT)
      1. 3.1.1 VCCINT Load Step
    2. 3.2 Buck Regulators (Integrated)
      1. 3.2.1 1V2
      2. 3.2.2 1V2_VCCO
      3. 3.2.3 1V2_MEM
      4. 3.2.4 2V5_DDR_VPP
      5. 3.2.5 3V3_VCCO
    3. 3.3 Linear Regulators
      1. 3.3.1 DDR Termination
      2. 3.3.2 0V92
      3. 3.3.3 1V5_GTY
      4. 3.3.4 1V5
      5. 3.3.5 5V0_SYS
    4. 3.4 Sequencing
      1. 3.4.1 TPS7H3014-SP Sequencer
      2. 3.4.2 TPS7H2221-SEP Discharge Circuit
      3. 3.4.3 VCCINT Discharge Circuit
  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 Discrete Buck Regulator (VCCINT)
        1. 4.3.1.1 0V8
      2. 4.3.2 Buck Regulators (Integrated)
        1. 4.3.2.1 1V2
        2. 4.3.2.2 1V2_VCCO
        3. 4.3.2.3 1V2_MEM
        4. 4.3.2.4 2V5_DDR_VPP
        5. 4.3.2.5 3V3_VCCO
      3. 4.3.3 Linear Regulators
        1. 4.3.3.1 0V6_VTT
        2. 4.3.3.2 0V92
        3. 4.3.3.3 1V5_GTY
        4. 4.3.3.4 1V5
        5. 4.3.3.5 5V0_SYS
  11. 5Design and Documentation Support
    1. 5.1 Design Files
      1. 5.1.1 Schematics
      2. 5.1.2 BOM
      3. 5.1.3 Layout Prints
    2. 5.2 Documentation Support
    3. 5.3 Support Resources
    4. 5.4 Trademarks
  12. 6About the Author

3.3.5 5V0_SYS

The TPS73801-SEP is selected to generate the 5.0V rail from the 12V0_SYS rail. This rail is used to power the TPS7H3014-SP pullup inputs and power for the TPS7H2221-SEP devices. These are all relatively low power. The TPS73801 is sized for 50mA for plenty of margin.

Output capacitors of 1x100μF + 2x22µF are selected for the output. EN is tied high to start-up right away so that this rail is usable for the TPS7H2221 and TPS7H3014 as soon as possible.

Figure 3-23 shows the 5V0_SYS schematic and Figure 3-24 shows the layout.

TIDA-050088 5V0_SYS Schematic Figure 3-23 5V0_SYS Schematic
TIDA-050088 5V0_SYS Layout Figure 3-24 5V0_SYS Layout