SLVSAE3A August   2010  – January 2016 TPS650231

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Pin Configuration and Functions
  7. 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  Electrical Characteristics: Control Signals
    7. 7.7  Electrical Characteristics: Supply Pins VCC, VINDCDC1, VINDCDC2, VINDCDC3, VINDCDC13
    8. 7.8  Electrical Characteristics: Supply Pins VBACKUP, VSYSIN, VRTC, VINLDO
    9. 7.9  Electrical Characteristics: VDCDC1 Step-Down Converter
    10. 7.10 Electrical Characteristics: VDCDC2 Step-Down Converter
    11. 7.11 Electrical Characteristics: VDCDC3 Step-Down Converter
    12. 7.12 Timing Requirements
    13. 7.13 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagrams
    3. 8.3 Feature Description
      1. 8.3.1  VRTC Output and Operation With or Without Backup Battery
      2. 8.3.2  Step-Down Converters, VDCDC1, VDCDC2, and VDCDC3
      3. 8.3.3  Power Save Mode Operation
      4. 8.3.4  Low-Ripple Mode
      5. 8.3.5  Soft-Start
      6. 8.3.6  100% Duty Cycle Low-Dropout Operation
      7. 8.3.7  Active Discharge When Disabled
      8. 8.3.8  Power-Good Monitoring
      9. 8.3.9  Low-Dropout Voltage Regulators
      10. 8.3.10 Undervoltage Lockout
      11. 8.3.11 Power-Up Sequencing
      12. 8.3.12 System Reset + Control Signals
        1. 8.3.12.1 DEFLDO1 and DEFLDO2
        2. 8.3.12.2 Interrupt Management and the INT Pin
    4. 8.4 Device Functional Modes
    5. 8.5 Programming
      1. 8.5.1 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)
      3. 8.6.3 MASK Register Address: 02h (Read or Write), Default Value: C0h
      4. 8.6.4 REG_CTRL Register Address: 03h (Read or Write), Default Value: FFh
      5. 8.6.5 CON_CTRL Register Address: 04h (Read or Write), Default Value: B1h
      6. 8.6.6 CON_CTRL2 Register Address: 05h (Read or Write), Default Value: 40h
      7. 8.6.7 DEFCORE Register Address: 06h (Read or Write), Default Value: 14h/1Eh
      8. 8.6.8 DEFSLEW Register Address: 07h (Read or Write), Default Value: 06h
      9. 8.6.9 LDO_CTRL Register Address: 08h (Read or Write), Default Value: Set with DEFLDO1 and DEFLDO2
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Input Voltage Connection
      2. 9.1.2 Unused Regulators
      3. 9.1.3 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
    1. 10.1 Requirements for Supply Voltages Below 3.0 V
  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 Community Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

10 Power Supply Recommendations

10.1 Requirements for Supply Voltages Below 3.0 V

For a supply voltage on pins VCC, VINDCDC1, VINDCDC2, and VINDCDC3 below 3.0 V, TI recommends enabling the DCDC1, DCDC2, and DCDC3 converters in sequence. If all 3 step-down converters are enabled at the same time while the supply voltage is close to the internal reset detection threshold, a reset may be generated during power-up. Therefore, TI recommends enabling the DC-DC converters in sequence. This can be done by driving one or two of the enable pins with a RC delay or by driving the enable pin by the output voltage of one of the other step-down converters. If a voltage above 3.0 V is applied on pin VBACKUP while VCC and VINDCDCx is below 3.0 V, there is no restriction in the power-up sequencing as VBACKUP is used to power the internal circuitry.