SLLS636N December   2004  – January 2015 MC33063A , MC34063A

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Description
  3. 3 Simplified Schematic
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 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—Oscillator
    6. 6.6 Electrical Characteristics—Output Switch
    7. 6.7 Electrical Characteristics—Comparator
    8. 6.8 Electrical Characteristics—Total Device
    9. 6.9 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
    4. 7.4 Device Functional Modes
      1. 7.4.1 Standard operation
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 External Switch Configurations for Higher Peak Current
    2. 8.2 Typical Application
      1. 8.2.1 Voltage-Inverting Converter Application
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Performance
      2. 8.2.2 Step-Up Converter Application
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Performance
      3. 8.2.3 Step-Down Converter Application
        1. 8.2.3.1 Design Requirements
        2. 8.2.3.2 Detailed Design Procedure
        3. 8.2.3.3 Application Performance
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Related Links
    2. 11.2 Trademarks
    3. 11.3 Electrostatic Discharge Caution
    4. 11.4 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7 Detailed Description

7.1 Overview

The MC33063A and MC34063A devices are easy-to-use ICs containing all the primary circuitry needed for building simple DC-DC converters. These devices primarily consist of an internal temperature-compensated reference, a comparator, an oscillator, a PWM controller with active current limiting, a driver, and a high-current output switch. Thus, the devices require minimal external components to build converters in the boost, buck, and inverting topologies.

The MC33063A device is characterized for operation from –40°C to 85°C, while the MC34063A device is characterized for operation from 0°C to 70°C.

7.2 Functional Block Diagram

fbd_lls636.gif

7.3 Feature Description

  • Wide Input Voltage Range: 3 V to 40 V
  • High Output Switch Current: Up to 1.5 A
  • Adjustable Output Voltage
  • Oscillator Frequency Up to 100 kHz
  • Precision Internal Reference: 2%
  • Short-Circuit Current Limiting
  • Low Standby Current

7.4 Device Functional Modes

7.4.1 Standard operation

Based on the application, the device can be configured in multiple different topologies. See the Application and Implementation section for how to configure the device in several different operating modes.