SLVSBF0C JULY   2012  – April 2019 TPS53015

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Application
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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 Drivers
      2. 7.3.2 5-Volt Regulator
      3. 7.3.3 Soft-Start and Pre-biased Soft-Start Time
      4. 7.3.4 Overcurrent Protection
      5. 7.3.5 Overvoltage and Undervoltage Protection
      6. 7.3.6 UVLO Protection
      7. 7.3.7 Thermal Shutdown
      8. 7.3.8 Power Good
    4. 7.4 Device Functional Modes
      1. 7.4.1 PWM Operation
      2. 7.4.2 Auto-skip Eco-Mode Control
  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 Determine the Inductance Value
        2. 8.2.2.2 Output Capacitor
        3. 8.2.2.3 Input Capacitor
        4. 8.2.2.4 Bootstrap Capacitor
        5. 8.2.2.5 VREG5 Capacitor
        6. 8.2.2.6 Choose Output Voltage Resistors
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Trademarks
    2. 11.2 Electrostatic Discharge Caution
    3. 11.3 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.4 Overcurrent Protection

The TPS53015 device has a cycle-by-cycle over current limit feature. The over current limits the inductor valley current by monitoring the voltage drop across the low-side MOSFET RDS(on) during the low-side driver on-time. If the inductor current is larger than the overcurrent limit (OCL), the device delays the start of the next switching cycle until the sensed inductor current falls below the OCL current. MOSFET RDS(on) current sensing is used to provide an accuracy and cost effective solution without external devices. To program the OCL, a resister should be connected between DRVL and PGND. The recommended values are given inTable 1.

Table 1. OCL Resistor Values

Resistor Value ( kΩ) VTRIP (V)
6.8 0.050
11 0.087
18 0.125
27 0.174
39 0.224
56 0.274
75 0.336

Use Equation 1 to calculate IOCL.

Equation 1. TPS53015 eq3_slvsbf1.gif

The trip voltage is set between 0.05 V to 0.336 V over all operational temperature, including the 4000ppm/°C temperature slope compensation for the temperature dependency of the RDS(on). If the load current exceeds the overcurrent limit, the voltage begins to drop. If the overcurrent conditions continues the output voltage falls below the undervoltage protection threshold and the device shuts down.