SGLS384B May   2008  – October 2024 UC2843A-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
    1.     Pin 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
    6. 5.6 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 Pulse-by-Pulse Current Limiting
      2. 6.3.2 Current Sense Circuit
      3. 6.3.3 Error Amplifier Configuration
      4. 6.3.4 Undervoltage Lockout
      5. 6.3.5 Oscillator
    4. 6.4 Device Functional Modes
      1. 6.4.1 Normal Operation
      2. 6.4.2 Undervoltage Lockout (UVLO) Start-Up
      3. 6.4.3 UVLO Turnoff Mode
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
  9. 8 Power Supply Recommendations
  10. 9 Layout
    1. 9.1 Layout Guidelines
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Development Support
        1. 10.1.1.1 Custom Design With WEBENCH® Tools
      2. 10.1.2 Device Nomenclature
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
    3. 10.3 Related Links
    4. 10.4 Receiving Notification of Documentation Updates
    5. 10.5 Support Resources
    6. 10.6 Trademarks
    7. 10.7 Electrostatic Discharge Caution
    8. 10.8 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

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

3 Description

The UC2843A-Q1 control device is a pin-for-pin compatible improved version of the UC2843. Providing the necessary features to control current mode switched mode power supplies, this device has the following improved features. Start up current is specified to be less than 0.5mA. Oscillator discharge is trimmed to 8.3mA. During undervoltage lockout, the output stage can sink at least 10mA at less than 1.2V for VCC over 5V.

Package Information
PART NUMBERPACKAGE(1)PACKAGE SIZE(2)
UC2843A-Q1D (SOIC, 8) 4.90mm x 6.00mm
(1) For all available packages, see the orderable addendum at the end of the data sheet.
(2) The package size (length × width) is a nominal value and includes pins, where applicable.
Device Comparison Table
DEVICEUVLO ONUVLO OFFMAX DUTY CYCLE
UC2843A-Q18.5V7.9V<100%
UC2843A-Q1 Simplified Application DiagramSimplified Application Diagram