SBVS012I December   2000  – September 2020 DCP010505B , DCP010505DB , DCP010507DB , DCP010512B , DCP010512DB , DCP010515B , DCP010515DB , DCP011512DB , DCP011515DB , DCP012405B , DCP012415DB

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
    1.     Pin Functions
  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 Switching Characteristics
    7. 6.7 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagrams
    3. 7.3 Feature Description
      1. 7.3.1  Isolation
        1. 7.3.1.1 Operation or Functional Isolation
        2. 7.3.1.2 Basic or Enhanced Isolation
        3. 7.3.1.3 Continuous Voltage
        4. 7.3.1.4 Isolation Voltage
        5. 7.3.1.5 Repeated High-Voltage Isolation Testing
      2. 7.3.2  Power Stage
      3. 7.3.3  Oscillator And Watchdog Circuit
      4. 7.3.4  Thermal Shutdown
      5. 7.3.5  Synchronization
      6. 7.3.6  Light Load Operation (< 10%)
      7. 7.3.7  Load Regulation (10% to 100%)
      8. 7.3.8  Construction
      9. 7.3.9  Thermal Management
      10. 7.3.10 Power-Up Characteristics
    4. 7.4 Device Functional Modes
      1. 7.4.1 Disable and Enable (SYNCIN Pin)
      2. 7.4.2 Decoupling
        1. 7.4.2.1 Ripple Reduction
        2. 7.4.2.2 Connecting the DCP01B in Series
        3. 7.4.2.3 Connecting the DCP01B in Parallel
  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 Input Capacitor
        2. 8.2.2.2 Output Capacitor
        3. 8.2.2.3 SYNCIN Pin
      3. 8.2.3 DCP010505 Application Curves
      4. 8.2.4 PCB Design
      5. 8.2.5 Decoupling Ceramic Capacitors
      6. 8.2.6 Input Capacitor and the Effects of ESR
      7. 8.2.7 Ripple and Noise
        1. 8.2.7.1 Output Ripple Calculation Example
      8. 8.2.8 Dual DCP01B Output Voltage
      9. 8.2.9 Optimizing Performance
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Device Nomenclature
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Support Resources
    5. 11.5 Trademarks
    6. 11.6 Glossary
    7. 11.7 Electrostatic Discharge Caution
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

Input Capacitor and the Effects of ESR

If the input decoupling capacitor is not ceramic (and has an ESR greater than  20 mΩ), then at the instant the power transistors switch on, the voltage at the input pins falls momentarily. If the voltage falls below approximately 4 V, the device detects an undervoltage condition and switches the internal drive circuits to a momentary off state. This detection is carried out as a precaution against a genuine low input voltage condition that could slow down or even stop the internal circuits from operating correctly. A slow-down or stoppage results in the drive transistors being turned on too long, causing saturation of the transformer and destruction of the device.

Following detection of a low input voltage condition, the device switches off the internal drive circuits until the input voltage returns to a safe value, at which time the device tries to restart. If the input capacitor is still unable to maintain the input voltage, shutdown recurs. This process repeats until the input capacitor charges sufficiently to start the device correctly.

Normal start-up should occur in approximately 1 ms after power is applied to the device. If a considerably longer start-up duration time is encountered, it is likely that either (or both) the input supply or the capacitors are not performing adequately.

For 5-V to 15-V input devices, a 2.2-μF, low-ESR ceramic capacitor ensures good startup performance. For 24-V input voltage devices, 0.47-μF ceramic capacitors are recommended. Tantalum capacitors are not recommended, since most do not have low-ESR values and will degrade performance. If tantalum capacitors must be used, close attention must be paid to both the ESR and voltage as derated by the vendor.

Note:

During the start-up period, these devices may draw maximum current from the input supply. If the input voltage falls below approximately 4 V, the devices may not start up. Connect a 2.2-μF ceramic capacitor close to the input pins.