SLVS010X january   1976  – june 2023 UA78L

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Pin Configuration and Functions
  7. 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: UA78L02 (Legacy Chip Only)
    6. 6.6  Electrical Characteristics: UA78L033 (New Chip Only)
    7. 6.7  Electrical Characteristics: UA78L05 (Both Legacy and New Chip)
    8. 6.8  Electrical Characteristics: UA78L12 (Both Legacy and New Chip)
    9. 6.9  Electrical Characteristics: UA78L06 (Legacy Chip Only)
    10. 6.10 Electrical Characteristics: UA78L08 (Legacy Chip Only)
    11. 6.11 Electrical Characteristics: UA78L09 (Legacy Chip Only)
    12. 6.12 Electrical Characteristics: UA78L10 (Legacy Chip Only)
    13. 6.13 Electrical Characteristics: UA78L15 (Both Legacy and New Chip)
    14. 6.14 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Current Limit
      2. 7.3.2 Thermal Shutdown
      3. 7.3.3 Dropout Voltage (VDO)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Normal Operation
      2. 7.4.2 Dropout Operation
  9. 8 Applications 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 Input and Output Capacitor Requirements
        2. 8.2.2.2 Power Dissipation (PD)
        3. 8.2.2.3 Estimating Junction Temperature
        4. 8.2.2.4 External Capacitor Requirements
        5. 8.2.2.5 Overload Recovery
        6. 8.2.2.6 Reverse Current
        7. 8.2.2.7 Polarity Reversal Protection
      3. 8.2.3 Application Curves
    3. 8.3 System Examples
      1. 8.3.1 Positive Regulator in Negative Configuration
      2. 8.3.2 Current Limiter Circuit
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Development Support
        1. 9.1.1.1 Evaluation Module
      2. 9.1.2 Device Nomenclature
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • D|8
  • PK|3
  • LP|3
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.2.2.6 Reverse Current

Excessive reverse current can damage this device. Reverse current flows through the emitter-base junction of the pass transistor instead of the normal conducting channel. At high magnitudes, this current flow degrades the long-term reliability of the device.

Conditions where reverse current can occur are outlined in this section, all of which can exceed the absolute maximum rating of VO ≤ VI + 7 V. These conditions are:

  • If the device has a large COUT and the input supply collapses with little or no load current
  • The output is biased when the input supply is not established
  • The output is biased above the input supply

If reverse current flow is expected in the application, use external protection to protect the device. Reverse current is not limited in the device, so external limiting is required if extended reverse voltage operation is anticipated. Limit reverse current to 5% or less of the rated output current of the device in the event this current cannot be avoided.

Figure 8-3 shows one approach for protecting the device.

GUID-20220330-SS0I-TTND-LZ1J-BRQFHWBB80KH-low.svg Figure 8-2 Example Circuit for Reverse Current Protection Using a Schottky Diode