SLVS719H June   2008  – June 2026 TL1963A

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics: TL1963A (for DCQ, KTT package)
    6. 5.6 Electrical Characteristics: TL1963A (for DCY Package)
    7. 5.7 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 SHDN
      2. 6.3.2 Dropout Voltage
      3. 6.3.3 Undervoltage Lockout
      4. 6.3.4 Thermal Shutdown
      5. 6.3.5 Current Limit
      6. 6.3.6 Overload Recovery
      7. 6.3.7 Output Voltage Noise
      8. 6.3.8 Protection Features
        1. 6.3.8.1 For Legacy Chip Only
        2. 6.3.8.2 For Both Legacy and New Chip
    4. 6.4 Device Functional Modes
      1. 6.4.1 Device Functional Mode Comparison
      2. 6.4.2 Normal Operation
      3. 6.4.3 Dropout Operation
      4. 6.4.4 Disabled
  8. 7 Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Input/Output Capacitance and Transient Response
      2. 7.1.2 Reverse Current
      3. 7.1.3 Feed-Forward Capacitor
      4. 7.1.4 Estimating Junction Temperature
      5. 7.1.5 Power Dissipation (PD)
    2. 7.2 Typical Applications
      1. 7.2.1 Kelvin Sense Connection with SENSE pin
      2. 7.2.2 Design Requirements
      3. 7.2.3 Detailed Design Procedure
      4. 7.2.4 Application Curve
      5. 7.2.5 Paralleling Regulators for Higher Output Current (Legacy chip only)
        1. 7.2.5.1 Design Requirements
        2. 7.2.5.2 Detailed Design Procedure (Legacy chip only)
        3. 7.2.5.3 Application Curve
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
      3. 7.4.3 Thermal Considerations
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Development Support
      2. 8.1.2 Device Nomenclature
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Trademarks
    5. 8.5 Electrostatic Discharge Caution
    6. 8.6 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

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

6.3.6 Overload Recovery

Like many IC power regulators, the TL1963A-xx has safe operating area protection. The safe area protection decreases the current limit as input-to-output voltage increases and keeps the power transistor inside a safe operating region for all values of input-to-output voltage. The design of the protection provides some output current at all values of input-to-output voltage up to the device breakdown.

The voltage drop across LDO (VIN - VOUT) and load current (IL) flowing through define the power dissipated (PDissip) across the LDO.

Equation 2. P D i s s i p = V I N - V O U T × I O U T

The power limiting circuit, monitors both the voltage drop (headroom, VIN - VOUT) across LDO and output load current (IOUT) flowing through. If PDissip crosses the defined SOA limits, the power limiting circuit, limits the load current (IOUT) flowing through.

When power is first turned on, as the input voltage rises, the output follows the input, allowing the regulator to start up into very heavy loads. During start-up, as the input voltage is rising, the input-to-output voltage differential is small, allowing the regulator to supply large output currents. With a high input voltage, a problem can occur wherein removal of an output short does not allow the output voltage to recover. Other regulators also exhibit this phenomenon, so it is not unique to the TL1963A-xx.

The problem occurs with a heavy output load when the input voltage is high and the output voltage is low. Common situations occur immediately after the removal of a short circuit or when the shutdown pin is pulled high after the input voltage has already been turned on. The load line for such a load can intersect the output current curve at two points. If this occurs, there are two stable output operating points for the regulator. With this double intersection, the input power supply may need to be cycled down to zero and brought up again to make the output recover.