SBVS013E October   2001  – July 2022 DCR010503 , DCR010505 , DCR011203 , DCR011205 , DCR012403 , DCR012405

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Isolation
        1. 8.3.1.1 Operation or Functional Isolation
        2. 8.3.1.2 Basic or Enhanced Isolation
        3. 8.3.1.3 Working Voltage
        4. 8.3.1.4 Isolation Voltage Rating
        5. 8.3.1.5 Repeated High-Voltage Isolation Testing
      2. 8.3.2  Power Stage
      3. 8.3.3  Rectification
      4. 8.3.4  Regulator
      5. 8.3.5  Oscillator and Watchdog
      6. 8.3.6  ERROR Flag
      7. 8.3.7  Synchronization
      8. 8.3.8  Construction
      9. 8.3.9  Thermal Considerations
      10. 8.3.10 Decoupling – Ripple Reduction
    4. 8.4 Device Functional Modes
      1. 8.4.1 Device Disable and Enable
      2. 8.4.2 Regulated Output Disable and Enable
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 DCR01 Single Voltage Output
      2. 9.1.2 Generating Two Positive Output Voltages
      3. 9.1.3 Generation of Dual Polarity Voltages from Two Self-Synchronized DCR01s
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Input Capacitor
        2. 9.2.2.2 Output Capacitor
        3. 9.2.2.3 Filter Capacitor
        4. 9.2.2.4 ERROR Flag
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Examples
  12. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    2. 12.2 Support Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

8.3.10 Decoupling – Ripple Reduction

Due to the very low forward resistance of the DMOS switching transistors, high current demands are placed upon the input supply for a short time. By using a good-quality low Equivalent Series Resistance (ESR) capacitor of 2.2 μF (minimum) for the 5-V input devices and a 0.47-μF capacitor for the 12-V and 24-V devices, placed close to the IC supply input pins, the effects on the power supply can be minimized.

The high switching frequency of 400 kHz allows relatively small values of capacitors to be used for filtering the rectified output voltage. A good-quality, low-ESR, 1-μF ceramic capacitor placed close to the VREC pin and output ground is required and reduces the ripple. The output at VREC is full wave rectified and produces a ripple of 800 kHz.

TI recommends that a 0.1-μF, low-ESR, ceramic capacitor is connected close to the output pin and ground to reduce noise on the output. The capacitor values listed are minimum values. If lower ripple is required, the filter capacitor must be increased in value to 2.2 μF.

As with all switching power supplies, the best performance is obtained with low-ESR, ceramic capacitors connected close to the device pins. If low-ESR, ceramic capacitors are not used, the ESR generates a voltage drop when the capacitor is supplying the load power. Often a larger capacitor is chosen for this purpose, when a low-ESR, smaller capacitor performs as well.

Note:

TI does not recommend that the DCR01 be fitted using an IC socket, as this degrades performance.