SGLS384A May   2008  – November 2022 UC2843A-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Electrical Characteristics
    5. 6.5 Thermal Information
    6. 6.6 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Pulse-by-Pulse Current Limiting
      2. 7.3.2 Current Sense Circuit
      3. 7.3.3 Error Amplifier Configuration
      4. 7.3.4 Undervoltage Lockout
      5. 7.3.5 Oscillator
    4. 7.4 Device Functional Modes
      1. 7.4.1 Normal Operation
      2. 7.4.2 Undervoltage Lockout (UVLO) Start-Up
      3. 7.4.3 UVLO Turnoff Mode
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 Custom Design With WEBENCH® Tools
      2. 11.1.2 Device Nomenclature
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Related Links
    4. 11.4 Receiving Notification of Documentation Updates
    5. 11.5 Support Resources
    6. 11.6 Trademarks
    7. 11.7 Electrostatic Discharge Caution
    8. 11.8 Glossary
  12. 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 0.5 mA. Oscillator discharge is trimmed to 8.3 mA. During undervoltage lockout, the output stage can sink at least 10 mA at less than 1.2 V for VCC over 5 V.

Device Information(1)
PART NUMBERPACKAGEBODY SIZE (NOM)
UC2843A-Q1SOIC (8)5.80 mm × 4.81 mm
(1) For all available packages, see the orderable addendum at the end of the data sheet.
Device Comparison Table
DEVICEUVLO ONUVLO OFFMAX DUTY CYCLE
UC2843A-Q18.5 V7.9 V<100%
GUID-CCADA895-41C8-456C-96FB-20E2FB85EB61-low.gifSimplified Application Diagram