SLUU274A May   2007  – January 2022 TPS40193

 

  1.   Trademarks
  2. 1Introduction
    1. 1.1 Description
    2. 1.2 Applications
    3. 1.3 Features
  3. 2TPS40193EVM-001 Electrical Performance Specifications
  4. 3Schematic
  5. 4General Configuration and Description
    1. 4.1 Adjusting Output Voltage (R7)
    2. 4.2 Adjusting Short-Circuit Protection (R9)
    3. 4.3 Disable Jumper (JP1)
    4. 4.4 Test Point Descriptions
      1. 4.4.1 Input Voltage Monitoring (TP1, TP2)
      2. 4.4.2 Power-Good (TP3, TP4, TP5)
      3. 4.4.3 Compensation and Initialization (TP6)
      4. 4.4.4 Switching Waveforms (TP7, TP8, TP9, TP10)
      5. 4.4.5 Loop Analysis (TP11, TP12, TP13, TP14)
      6. 4.4.6 Output Voltage and Monitoring (TP15, TP16)
      7. 4.4.7 Pre-Bias Input (TP17)
  6. 5Test Setup
    1. 5.1 Equipment
      1. 5.1.1 Voltage Source
      2. 5.1.2 Meters
      3. 5.1.3 Loads
      4. 5.1.4 Oscilloscope
      5. 5.1.5 Recommended Wire Gauge
      6. 5.1.6 Other
    2. 5.2 Equipment Setup
    3. 5.3 Start-Up/Shutdown Procedure
    4. 5.4 Output Ripple Voltage Measurement Procedure
    5. 5.5 Control Loop Gain and Phase Measurement Procedure
    6. 5.6 Equipment Shutdown
  7. 6TPS40193EVM-001 Typical Performance Data and Characteristic Curves
    1. 6.1 Efficiency
    2. 6.2 Line and Load Regulation
    3. 6.3 Output Voltage Ripple
    4. 6.4 Switch Node
    5. 6.5 Control Loop Bode Plot
      1. 6.5.1 Low Line (VIN = 8 V)
      2. 6.5.2 High Line (VIN = 14 V)
  8. 7EVM Assembly Drawings and Layout
  9. 8Bill of Materials
  10. 9Revision History

4.2 Adjusting Short-Circuit Protection (R9)

The TPS40193 uses a selectable current limit for short-circuit protection. The current limit is selected from three predefined levels by placing a resistor at R9. The TPS40193 compares the voltage drop across the high-side FET (VDD to SW) to an internal reference voltage selected during start-up. Table 4-2 shows the voltage levels.

Table 4-2 Adjusting VSCP with R9
VSCP (min) R7 (kΩ)
88mV 3.9
160mV Open
228mV 12

The current before declaring short-circuit protection can be determined by dividing the VSCP by the RDS(ON) of the high-side FET (Q2).