SLUSEC8A March   2021  – June 2022 TPS628501 , TPS628502 , TPS628503

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Device Comparison Table
  6. Pin Configuration and Functions
  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 Typical Characteristics
  8. Parameter Measurement Information
    1. 8.1 Schematic
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Precise Enable (EN)
      2. 9.3.2 COMP/FSET
      3. 9.3.3 MODE / SYNC
      4. 9.3.4 Spread Spectrum Clocking (SSC)
      5. 9.3.5 Undervoltage Lockout (UVLO)
      6. 9.3.6 Power Good Output (PG)
      7. 9.3.7 Thermal Shutdown
    4. 9.4 Device Functional Modes
      1. 9.4.1 Pulse Width Modulation (PWM) Operation
      2. 9.4.2 Power Save Mode Operation (PWM/PFM)
      3. 9.4.3 100% Duty-Cycle Operation
      4. 9.4.4 Current Limit and Short Circuit Protection
      5. 9.4.5 Foldback Current Limit and Short Circuit Protection
      6. 9.4.6 Output Discharge
      7. 9.4.7 Soft Start
      8. 9.4.8 Input Overvoltage Protection
  10. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 Programming the Output Voltage
      2. 10.1.2 Inductor Selection
      3. 10.1.3 Capacitor Selection
        1. 10.1.3.1 Input Capacitor
        2. 10.1.3.2 Output Capacitor
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
      3. 10.2.3 Application Curves
    3. 10.3 System Examples
      1. 10.3.1 Synchronizing to an External Clock
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 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
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

Overview

The TPS62850x synchronous switch mode power converters are based on a peak current mode control topology. The control loop is internally compensated.

To optimize the bandwidth of the control loop to the wide range of output capacitance that can be used with TPS62850x, the internal compensation has two settings. See Section 9.3.2. One out of the two compensation settings is chosen either by a resistor from COMP/FSET to GND, or by the logic state of this pin. The regulation network achieves fast and stable operation with small external components and low-ESR ceramic output capacitors. The devices can be operated without a feedforward capacitor on the output voltage divider, however, using a typically 10-pF feedforward capacitor improves transient response.

The devices support forced fixed frequency PWM operation with the MODE pin tied to a logic high level. The frequency is defined as either 2.25 MHz internally fixed when COMP/FSET is tied to GND or VIN, or in a range of 1.8 MHz to 4 MHz defined by a resistor from COMP/FSET to GND. Alternatively, the devices can be synchronized to an external clock signal in a range from 1.8 MHz to 4 MHz, applied to the MODE pin with no need for additional passive components. An internal PLL allows the internal clock to be changed to an external clock during operation. The synchronization to the external clock is done on a falling edge of the clock applied at MODE to the rising edge on the SW pin. This allows a roughly 180° phase shift when the SW pin is used to generate the synchronization signal for a second converter. When the MODE pin is set to a logic low level, the device operates in power save mode (PFM) at low output current and automatically transfers to fixed frequency PWM mode at higher output current. In PFM mode, the switching frequency decreases linearly based on the load to sustain high efficiency down to very low output current.