SLVS670L June   2006  – May 2018 TPS65023 , TPS65023B

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Simplified Schematic
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 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  Electrical Characteristics: Supply Pins VCC, VINDCDC1, VINDCDC2, VINDCDC3
    7. 6.7  Electrical Characteristics: Supply Pins VBACKUP, VSYSIN, VRTC, VINLDO
    8. 6.8  Electrical Characteristics: VDCDC1 Step-Down Converter
    9. 6.9  Electrical Characteristics: VDCDC2 Step-Down Converter
    10. 6.10 Electrical Characteristics: VDCDC3 Step-Down Converter
    11. 6.11 I2C Timing Requirements for TPS65023B
    12. 6.12 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  VRTC Output and Operation With or Without Backup Battery
      2. 7.3.2  Step-Down Converters, VDCDC1, VDCDC2, and VDCDC3
      3. 7.3.3  Power Save Mode Operation
      4. 7.3.4  Low Ripple Mode
      5. 7.3.5  Soft-Start
      6. 7.3.6  100% Duty Cycle Low Dropout Operation
      7. 7.3.7  Active Discharge When Disabled
      8. 7.3.8  Power-Good Monitoring
      9. 7.3.9  Low-Dropout Voltage Regulators
      10. 7.3.10 Undervoltage Lockout
      11. 7.3.11 Power-Up Sequencing
    4. 7.4 Device Functional Modes
    5. 7.5 Programming
      1. 7.5.1 System Reset + Control Signals
        1. 7.5.1.1 DEFLDO1 and DEFLDO2
        2. 7.5.1.2 Interrupt Management and the INT Pin
      2. 7.5.2 Serial Interface
    6. 7.6 Register Maps
      1. 7.6.1 VERSION Register Address: 00h (Read Only)
      2. 7.6.2 PGOODZ Register Address: 01h (Read Only)
      3. 7.6.3 MASK Register Address: 02h (Read and Write), Default Value: C0h
      4. 7.6.4 REG_CTRL Register Address: 03h (Read and Write), Default Value: FFh
      5. 7.6.5 CON_CTRL Register Address: 04h (Read and Write), Default Value: B1h
      6. 7.6.6 CON_CTRL2 Register Address: 05h (Read and Write), Default Value: 40h
      7. 7.6.7 DEFCORE Register Address: 06h (Read and Write), Default Value: 14h/1Eh
      8. 7.6.8 DEFSLEW Register Address: 07h (Read and Write), Default Value: 06h
      9. 7.6.9 LDO_CTRL Register Address: 08h (Read and Write), Default Value: Set with DEFLDO1 and DEFLDO2
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Input Voltage Connection
      2. 8.1.2 Unused Regulators
      3. 8.1.3 Reset Condition of DCDC1
    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 for the DC-DC Converters
        2. 8.2.2.2 Output Capacitor Selection
        3. 8.2.2.3 Input Capacitor Selection
        4. 8.2.2.4 Output Voltage Selection
        5. 8.2.2.5 VRTC Output
        6. 8.2.2.6 LDO1 and LDO2
        7. 8.2.2.7 TRESPWRON
        8. 8.2.2.8 VCC Filter
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
    1. 9.1 Requirements for Supply Voltages Below 3.0 V
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
      2. 11.1.2 Development Support
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Related Links
    4. 11.4 Community Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

8.2.2.1 Inductor Selection for the DC-DC Converters

Each of the converters in the TPS65023x typically use 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 has to 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 must be selected for highest efficiency.

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

Equation 8 calculates the maximum inductor current under static load conditions. The saturation current of the inductor must be rated higher than the maximum inductor current as calculated with Equation 8. This is needed because during heavy load transient the inductor current rises above the calculated value.

Equation 8. TPS65023 TPS65023B q4_delta_lvs607.gif
Equation 9. TPS65023 TPS65023B q5_ilmax_lvs607.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 conservative approach is to select the inductor current rating just for the maximum switch current of the TPS65023x (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 18 and the typical applications for possible inductors.

Table 18. Tested Inductors

DEVICE INDUCTOR VALUE TYPE COMPONENT SUPPLIER
All converters 2.2 μH LPS4012-222LMB Coilcraft
2.2 μH VLCF4020T-2R2N1R7 TDK
For DCDC2 or DCDC3 2.2 uH LQH32PN2R2NN0 Murata
For DCDC1 1.5 uH LQH32PN1R5NN0 Murata
All converters 2.2 uH PST25201B-2R2MS Cyntec