SLVS979C October   2009  – May 2018 TPS65720 , TPS65721

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Typical Application Schematic
  4. 4 Revision History
  5. 5 Device Options
  6. 6 Pin Configuration and Functions
    1.     Pin Functions—DSBGA (TPS65720)
    2.     Pin Functions—DSBGA (TPS657201, TPS657202)
    3.     Pin Functions—WQFN (TPS65721)
  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 Dissipation Ratings
    7. 7.7 Timing Requirements
    8. 7.8 Switching Characteristics
    9. 7.9 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  Battery Charger and Power Path
      2. 8.3.2  Power-Path Management
      3. 8.3.3  Battery Charging
        1. 8.3.3.1 I-PRECHARGE
        2. 8.3.3.2 ITERM
        3. 8.3.3.3 Battery Detection and Recharge
        4. 8.3.3.4 Charge Termination On/Off
        5. 8.3.3.5 Timers
        6. 8.3.3.6 Dynamic Timer Function
        7. 8.3.3.7 Charger Fault
      4. 8.3.4  Thermal Regulation and Thermal Shutdown
      5. 8.3.5  Battery Pack Temperature Monitoring
      6. 8.3.6  DCDC1 Converter
      7. 8.3.7  Power Save Mode
        1. 8.3.7.1 Dynamic Voltage Positioning
        2. 8.3.7.2 Soft Start
        3. 8.3.7.3 100% Duty Cycle Low Dropout Operation
        4. 8.3.7.4 Undervoltage Lockout
      8. 8.3.8  Short-Circuit Protection
      9. 8.3.9  Thermal Shutdown
      10. 8.3.10 LDO1
        1. 8.3.10.1 Default Voltage Setting for LDOs and DCDC1
        2. 8.3.10.2 Internal Analog Multiplexer (BAT, TS, TS_OUT); TPS657201, TPS657202 Only
        3. 8.3.10.3 Internal Battery Voltage Comparator
        4. 8.3.10.4 GPIOs, LED Drivers
        5. 8.3.10.5 RESET Output
        6. 8.3.10.6 Threshold Input (TPS65721 Only)
          1. 8.3.10.6.1 ENABLE for DCDC1 and LDO1
          2. 8.3.10.6.2 PB_IN Input
          3. 8.3.10.6.3 HOLD_DCDC1 Input
          4. 8.3.10.6.4 HOLD_LDO1 Input
          5. 8.3.10.6.5 INT Output
    4. 8.4 Device Functional Modes
      1. 8.4.1 Power Down
      2. 8.4.2 Sleep Mode
      3. 8.4.3 Standby Mode
      4. 8.4.4 Power-On Reset Mode
      5. 8.4.5 Idle Mode
    5. 8.5 Programming
      1. 8.5.1 Serial Interface
    6. 8.6 Register Maps
      1. 8.6.1  CHGSTATUS Register Address: 01h (read only)
      2. 8.6.2  CHGCONFIG0 Register Address: 02h (read/write)
      3. 8.6.3  CHGCONFIG1 Register Address: 03h (read/write)
      4. 8.6.4  CHGCONFIG2 Register Address: 04h (read/write)
      5. 8.6.5  CHGCONFIG3 Register Address: 05h (read/write)
      6. 8.6.6  CHGSTATE Register Address: 06h (read only)
      7. 8.6.7  DEFDCDC1 Register Address: 07h (read/write)
      8. 8.6.8  LDO_CTRL Register Address: 08h (read/write)
      9. 8.6.9  CONTROL0 Register Address: 09h (read/write)
      10. 8.6.10 CONTROL1 Register Address: 0Ah (read/write)
      11. 8.6.11 GPIO_SSC Register Address: 0Bh (read/write)
      12. 8.6.12 GPIODIR Register Address: 0Ch (read/write)
      13. 8.6.13 IRMASK0 Register Address: 0Dh (read/write)
      14. 8.6.14 IRMASK1 Register Address: 0Eh (read/write)
      15. 8.6.15 IRMASK2 Register Address: 0Fh (read/write)
      16. 8.6.16 IR0 Register Address: 10h (read only)
      17. 8.6.17 IR1 Register Address: 11h (read)
      18. 8.6.18 IR2 Register Address: 12h (read)
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Output Voltage Setting
          1. 9.2.2.1.1 DCDC1
          2. 9.2.2.1.2 LDO1
        2. 9.2.2.2 Output Filter Design (Inductor and Output Capacitor)
          1. 9.2.2.2.1 Inductor Selection
          2. 9.2.2.2.2 Output Capacitor Selection
          3. 9.2.2.2.3 Input Capacitor Selection
        3. 9.2.2.3 Charger/Power Path
          1. 9.2.2.3.1 Charger Stability
          2. 9.2.2.3.2 Setting the Charge Current
          3. 9.2.2.3.3 Dynamic Power Path Management (DPPM)
      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 Related Links
    4. 12.4 Receiving Notification of Documentation Updates
    5. 12.5 Community Resources
    6. 12.6 Trademarks
    7. 12.7 Electrostatic Discharge Caution
    8. 12.8 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9.2.2.2.2 Output Capacitor Selection

The advanced Fast Response voltage mode control scheme of the step-down converter allows the use of small ceramic capacitors with a typical value of 10 μF, without having large output voltage under and overshoots during heavy load transients. Ceramic capacitors having low ESR values result in lowest output voltage ripple and are therefore recommended. For an inductor value of 3.3 μH, an output capacitor with 4.7 μF can be used. Refer to recommended components.

If ceramic output capacitors are used, the capacitor RMS ripple current rating will always meet the application requirements. Just for completeness the RMS ripple current is calculated by Equation 6:

Equation 6. TPS65720 TPS657201 TPS657202 TPS65721 eq4_irms_lvs979.gif

At nominal load current the inductive converters operate in PWM mode and the overall output voltage ripple is the sum of the voltage spike caused by the output capacitor ESR plus the voltage ripple caused by charging and discharging the output capacitor, as calculated by Equation 7:

Equation 7. TPS65720 TPS657201 TPS657202 TPS65721 eq5_dvout_lvs979.gif

Where the highest output voltage ripple occurs at the highest input voltage Vin.

At light load currents the converter operates in power save mode and the output voltage ripple is dependent on the output capacitor value. The output voltage ripple is set by the internal comparator delay and the external capacitor. The typical output voltage ripple is less than 1% of the nominal output voltage.