SLVS927F March   2009  – July 2018 TPS65023-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Pin Configuration and Functions
    1.     Pin 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 Timing Requirements
    7. 7.7 Typical Characteristics
  8. 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. 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

8.3.1 Step-Down Converters, VDCDC1, VDCDC2, and VDCDC3

The TPS65023-Q1 incorporates three synchronous step-down converters operating typically at 2.25 MHz fixed-frequency pulse-width modulation (PWM) at moderate to heavy load currents. At light load currents, the converters automatically enter the power-save mode (PSM), and operate with pulse-frequency modulation (PFM). The VDCDC1 converter is capable of delivering 1.5-A output current, the VDCDC2 converter is capable of delivering 1.2 A, and the VDCDC3 converter is capable of delivering up to 1 A.

The converter output voltages can be programmed through the DEFDCDC1, DEFDCDC2, and DEFDCDC3 pins. The pins can either be connected to GND, VCC, or to a resistor divider between the output voltage and GND. The VDCDC1 converter defaults to 1.2 V or 1.6 V, depending on the DEFDCDC1 configuration pin. If DEFDCDC1 is tied to ground, the default is 1.2 V. If it is tied to VCC, the default is 1.6 V. When the DEFDCDC1 pin is connected to a resistor divider, the output voltage can be set in the range of 0.6 V to VCC. See Application and Implementation for more details. The core voltage can be reprogrammed through the serial interface in the range of 0.8 V to 1.6 V with a programmable slew rate. The converter is forced into PWM operation while any programmed voltage change is underway, whether the voltage is being increased or decreased. The DEFCORE and DEFSLEW registers are used to program the output voltage and slew rate during voltage transitions.

The VDCDC2 converter defaults to 1.8 V or 3.3 V, depending on the DEFDCDC2 configuration pin. If DEFDCDC2 is tied to ground, the default is 1.8 V. If it is tied to VCC, the default is 3.3 V. When the DEFDCDC2 pin is connected to a resistor divider, the output voltage can be set in the range of 0.6 V to VCC.

The VDCDC3 converter defaults to 1.8 V or 3.3 V, depending on the DEFDCDC3 configuration pin. If DEFDCDC3 is tied to ground, the default is 1.8 V. If it is tied to VCC, the default is 3.3 V. When the DEFDCDC3 pin is connected to a resistor divider, the output voltage can be set in the range of 0.6 V to VCC.

The step-down converter outputs (when enabled) are monitored by power good (PG) comparators, the outputs of which are available through the serial interface. The outputs of the DC-DC converters can be optionally discharged through on-chip 300-Ω resistors when the DC-DC converters are disabled.

During PWM operation, the converters use a unique fast-response voltage-mode controller scheme with input-voltage feed-forward to achieve good line and load regulation, allowing the use of small ceramic input and output capacitors. At the beginning of each clock cycle initiated by the clock signal, the P-channel MOSFET switch is turned on. The inductor current ramps up until the comparator trips and the control logic turns off the switch. The current-limit comparator also turns off the switch if the current limit of the P-channel switch is exceeded. After the adaptive dead time used to prevent shoot-through current, the N-channel MOSFET rectifier is turned on, and the inductor current ramps down. The next cycle is initiated by the clock signal, again turning off the N-channel rectifier and turning on the P-channel switch.

The three DC-DC converters operate synchronized to each other with the VDCDC1 converter as the master. A 180° phase shift between the VDCDC1 switch turnon and the VDCDC2 and a further 90° shift to the VDCDC3 switch turnon decreases the input rms current, and smaller input capacitors can be used. This is optimized for a typical application where the VDCDC1 converter regulates a Li-Ion battery voltage of 3.7 V to 1.2 V, the VDCDC2 converter from 3.7 V to 1.8 V, and the VDCDC3 converter from 3.7 V to 3.3 V. The phase of the three converters can be changed using the CON_CTRL register.