SLVSDY9A March   2017  – November 2022 TPS65263-1Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Adjusting the Output Voltage
      2. 7.3.2  Enable and Adjusting UVLO
      3. 7.3.3  Soft-Start Time
      4. 7.3.4  Power-Up Sequencing
      5. 7.3.5  V7V Low-Dropout Regulator and Bootstrap
      6. 7.3.6  Out-of-Phase Operation
      7. 7.3.7  Output Overvoltage Protection (OVP)
      8. 7.3.8  PSM
      9. 7.3.9  Slope Compensation
      10. 7.3.10 Overcurrent Protection
        1. 7.3.10.1 High-Side MOSFET Overcurrent Protection
        2. 7.3.10.2 Low-Side MOSFET Overcurrent Protection
      11. 7.3.11 Power Good
        1. 7.3.11.1 Adjustable Switching Frequency
      12. 7.3.12 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Serial Interface Description
      2. 7.4.2 I2C Update Sequence
    5. 7.5 Register Maps
      1. 7.5.1 VOUT2_SEL: Vout2 Voltage Selection Register (Address = 0x01H)
      2. 7.5.2 VOUT1_COM: Buck1 Command Register (offset = 0x03H)
      3. 7.5.3 VOUT2_COM: Buck2 Command Register (offset = 0x04H)
      4. 7.5.4 VOUT3_COM: Buck3 Command Register (offset = 0x05H)
      5. 7.5.5 SYS_STATUS: System Status Register (offset = 0x06H)
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Output Inductor Selection
        2. 8.2.2.2 Output Capacitor Selection
        3. 8.2.2.3 Input Capacitor Selection
        4. 8.2.2.4 Loop Compensation
      3. 8.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  9. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Electrostatic Discharge Caution
    5. 9.5 Glossary
  10. 10Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.8 PSM

The TPS65263-1Q1 can enter high-efficiency PSM operation at light load current. To enable PSM operation, set the VOUTx_COM register bit 1 to '1' through I2C interface.

When a controller is enabled for PSM operation, the peak inductor current is sensed and compared with 310-mA current typically. Because the integrated current comparator catches the peak inductor current only, the average load current entering PSM varies with the applications and external output filters. In PSM, the sensed peak inductor current is clamped at 310 mA, shown in Figure 7-10.

When a controller operates in PSM, the inductor current is not allowed to reverse. The reverse current comparator turns off the low-side MOSFET when the inductor current reaches 0, preventing it from reversing and going negative.

Due to the delay in the circuit and current comparator, tdly (typical 50 nS at Vin = 12 V), the real peak inductor current threshold to turn off high-side power MOSFET can shift higher depending on inductor inductance and input, output voltages. Calculate the threshold of peak inductor current to turn off high-side power MOSFET with Equation 6.

Equation 6. GUID-A02901E8-B447-4487-A4C1-75DAC2D0BA84-low.gif

After the charge accumulated on the Vout capacitor is more than loading need, the COMP pin voltage drops to a low voltage driven by the error amplifier. There is an internal comparator at COMP pin. If the comp voltage is <0.35 V, the power stage stops switching to save power.

GUID-0D99B57F-182C-4089-8982-3CF77E8E2B5B-low.gifFigure 7-10 PSM Current Comparator