SLVS927F March   2009  – July 2018 TPS65023-Q1

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
    1.     Device Images
      1.      Simplified Schematic
  4. Revision History
  5. Description (continued)
  6. Pin Configuration and Functions
    1.     Pin Functions
  7. Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Timing Requirements
    7. 7.7 Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Step-Down Converters, VDCDC1, VDCDC2, and VDCDC3
      2. 8.3.2 Soft Start
      3. 8.3.3 Active Discharge When Disabled
      4. 8.3.4 Power-Good Monitoring
      5. 8.3.5 Low-Dropout Voltage Regulators
      6. 8.3.6 Undervoltage Lockout
    4. 8.4 Device Functional Modes
      1. 8.4.1 VRTC Output and Operation With or Without Backup Battery
      2. 8.4.2 Power-Save Mode Operation (PSM)
      3. 8.4.3 Low-Ripple Mode
      4. 8.4.4 100% Duty-Cycle Low-Dropout Operation
      5. 8.4.5 System Reset and Control Signals
        1. 8.4.5.1 DEFLDO1 and DEFLDO2
        2. 8.4.5.2 Interrupt Management and the INT Pin
    5. 8.5 Programming
      1. 8.5.1 Power-Up Sequencing
      2. 8.5.2 Serial Interface
    6. 8.6 Register Maps
      1. 8.6.1 VERSION Register (address: 00h) Read-Only
      2. 8.6.2 PGOODZ Register (address: 01h) Read-Only
        1. Table 5. PGOODZ Register Field Descriptions
      3. 8.6.3 MASK Register (address: 02h)
      4. 8.6.4 REG_CTRL Register (address: 03h)
        1. Table 6. REG_CTRL Register Field Descriptions
      5. 8.6.5 CON_CTRL Register (address: 04h)
        1. Table 7. CON_CTRL Register Field Descriptions
      6. 8.6.6 CON_CTRL2 Register (address: 05h)
        1. Table 8. CON_CTRL2 Register Field Descriptions
      7. 8.6.7 DEFCORE Register (address: 06h)
        1. Table 9. DEFCORE Register Field Descriptions
      8. 8.6.8 DEFSLEW Register (address: 07h)
        1. Table 10. DEFSLEW Register Field Descriptions
      9. 8.6.9 LDO_CTRL Register (address: 08h)
        1. Table 11. LDO_CTRL Register Field Descriptions
  9. Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Reset Condition of DCDC1
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Inductor Selection for the DC-DC Converters
        2. 9.2.2.2 Output Capacitor Selection
        3. 9.2.2.3 Input Capacitor Selection
        4. 9.2.2.4 Output Voltage Selection
        5. 9.2.2.5 VRTC Output
        6. 9.2.2.6 LDO1 and LDO2
        7. 9.2.2.7 TRESPWRON
        8. 9.2.2.8 VCC Filter
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Community Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Inductor Selection for the DC-DC Converters

Each of the converters in the TPS65023-Q1 typically uses a 2.2-μH output inductor. Larger or smaller inductor values are used to optimize the performance of the device for specific operation conditions. The selected inductor must be rated for its DC resistance and saturation current. The DC resistance of the inductance influences directly the efficiency of the converter. Therefore, an inductor with lowest DC resistance should be selected for highest efficiency.

For a fast transient response, TI recommends a 2.2-μH inductor in combination with a 22-μF output capacitor.

Equation 4 calculates the maximum inductor current under static load conditions. The saturation current of the inductor should be rated higher than the maximum inductor current as calculated with Equation 4. This is needed because during a heavy load transient the inductor current rises above the value calculated under Equation 4.

Equation 4. TPS65023-Q1 q4_delta_lvs927.gif
Equation 5. TPS65023-Q1 q5_ilmax_lvs927.gif

where

  • f = Switching frequency (2.25 MHz typical)
  • L = Inductor value
  • ΔIL = Peak-to-peak inductor ripple current
  • ILMAX = Maximum inductor current

The highest inductor current occurs at maximum VIN.

Open-core inductors have a soft saturation characteristic, and they can usually handle higher inductor currents versus a comparable shielded inductor.

A more-conservative approach is to select the inductor current rating just for the maximum switch current of the TPS65023-Q1 (2 A for the VDCDC1 and VDCDC2 converters, and 1.5 A for the VDCDC3 converter). The core material from inductor to inductor differs and has an impact on the efficiency, especially at high switching frequencies.

See Table 12 and the typical applications for possible inductors.

Table 12. Tested Inductors

DEVICE INDUCTOR VALUE TYPE COMPONENT SUPPLIER
All converters 2.2 μH LPS4012-222LMB Coilcraft
2.2 μH VLCF4020T-2R2N1R7 TDK