SLVSEA0B january   2018  – june 2023 TPS61280D , TPS61280E , TPS61281D

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Description (continued)
  7. 6 Device Comparison Table
  8. 7 Pin Configuration and Functions
  9. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 I2C Interface Timing Characteristics #GUID-BD85FD7C-B9AF-4F5D-9DFF-CD61365A592A/SLVS5401494
    7. 8.7 I2C Timing Diagrams
    8. 8.8 Typical Characteristics
  10. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Voltage Scaling Management (VSEL)
      2. 9.3.2 Spread Spectrum, PWM Frequency Dithering
    4. 9.4 Device Functional Modes
      1. 9.4.1 Power-Save Mode
      2. 9.4.2 Pass-Through Mode
      3. 9.4.3 Mode Selection
      4. 9.4.4 Current Limit Operation
      5. 9.4.5 Start-Up and Shutdown Mode
      6. 9.4.6 Undervoltage Lockout
      7. 9.4.7 Thermal Shutdown
      8. 9.4.8 Fault State and Power-Good
    5. 9.5 Programming
      1. 9.5.1 Serial Interface Description (TPS61280D/E)
      2. 9.5.2 Standard-, Fast-, Fast-Mode Plus Protocol
      3. 9.5.3 HS-Mode Protocol
      4. 9.5.4 TPS6128xD/E I2C Update Sequence
    6. 9.6 Register Maps
      1. 9.6.1  Slave Address Byte
      2. 9.6.2  Register Address Byte
      3. 9.6.3  I2C Registers, E2PROM, Write Protect
      4. 9.6.4  E2PROM Configuration Parameters
      5. 9.6.5  CONFIG Register [reset = 0x01]
      6. 9.6.6  VOUTFLOORSET Register [reset = 0x02]
      7. 9.6.7  VOUTROOFSET Register [reset = 0x03]
      8. 9.6.8  ILIMSET Register [reset = 0x04]
      9. 9.6.9  Status Register [reset = 0x05]
      10. 9.6.10 E2PROMCTRL Register [reset = 0xFF]
  11. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 TPS61281D with 2.5V-4.35 VIN, 1500 mA Output Current (TPS61280D with default I2C Configuration)
        1. 10.2.1.1 Design Requirement
        2. 10.2.1.2 Detailed Design Parameters
          1. 10.2.1.2.1 Inductor Selection
          2. 10.2.1.2.2 Output Capacitor
          3. 10.2.1.2.3 Input Capacitor
          4. 10.2.1.2.4 Checking Loop Stability
        3. 10.2.1.3 Application Performance Curves
      2. 10.2.2 TPS61282D with 2.5V-4.35 VIN, 2000 mA Output Current (TPS61280D with I2C Programmable)
        1. 10.2.2.1 Design Requirements
        2. 10.2.2.2 Detailed Design Procedures
        3. 10.2.2.3 Application Performance Curves
  12. 11Power Supply Recommendations
  13. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
    3. 12.3 Thermal Information
  14. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Third-Party Products Disclaimer
    2. 13.2 Receiving Notification of Documentation Updates
    3. 13.3 Support Resources
    4. 13.4 Trademarks
    5. 13.5 Electrostatic Discharge Caution
    6. 13.6 Glossary
  15. 14Mechanical, Packaging, and Orderable Information
    1. 14.1 Package Summary

Package Options

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

9.4.3 Mode Selection

Depending on the settings of Section 9.6.5 the device can be operated at a quasi-constant 2.3-MHz frequency PWM mode or in automatic PFM/PWM mode. In this mode, the converter operates in pseudo-fixed frequency PWM mode at moderate to heavy loads and in the PFM mode during light loads, which maintains high efficiency over a wide load current range. For more details, see the Section 9.6.5 description.

The quasi-constant frequency PWM mode has the tightest regulation and the best line/load transient performance. In forced PWM mode, the device features a unique RDS(ON) management function to maintain high broadband efficiency as well as low resistance in pass-through mode.

In the TPS61280D/E device, the GPIO pin can be configured (via the Section 9.6.5) to select the operating mode of the device. In the other TPS6128xD/E devices, the MODE pin is used to select the operating mode. Pulling this pin high forces the converter to operate in the PWM mode even at light load currents. The advantage is that the converter modulates its switching frequency according to a spread spectrum PWM modulation technique allowing simple filtering of the switching harmonics in noise-sensitive applications.

For additional flexibility, it is possible to switch from power-save mode (GPIO or MODE input = L) to PWM mode (GPIO or MODE input = H) during operation. This allows efficient power management by adjusting the operation of the converter to the specific system requirements (that is, 2G RF PA Rx/Tx operation).

Entry to forced pass-through mode (nBYP = L) initiates with a current limited transition followed by a true bypass state. To prevent reverse current to the battery, the devices waits until the output discharges below the input voltage level before entering forced pass-through mode. Care should be taken to prohibit the output voltage from collapsing whilst transitioning into forced pass-through mode under heavy load conditions and/or limited output capacitance. This can be easily done by adding capacitance to the output of the converter. In forced pass-through mode, the output follows the input below the preset output threshold voltage (VOUT_TH).