SLUSC14A May   2015  – February 2019 UC1845A-SP

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
      2.      VREF Radiation Drift Curve
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
    1.     Pin 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 UVLO
      2. 8.3.2 Reference
      3. 8.3.3 Totem-Pole Output
    4. 8.4 Device Functional Modes
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Oscillator
        2. 9.2.2.2 Current Sensing and Limiting
        3. 9.2.2.3 Error Amplifier
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Feedback Traces
      2. 11.1.2 Input/Output Capacitors
      3. 11.1.3 Compensation Components
      4. 11.1.4 Traces and Ground Planes
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    2. 12.2 Community Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • FK|20
  • HKU|10
  • JG|8
Thermal pad, mechanical data (Package|Pins)
Orderable Information

3 Description

The UC1845A-SP control IC is a radiation hardened pin-for-pin compatible version of the UC184x family. It is primarily suited for Satellites and other harsh environment applications. Providing the necessary characteristics to control current-mode switched-mode power supplies, this device has improved features. Start-up current is specified to be less than 0.5 mA and oscillator discharge is trimmed to 8.3 mA. During UVLO, the output stage can sink at least 10 mA at less than 1.2 V for VCC over 5 V.

The Device Comparison Table shows the difference between members of this family. Reference the individual product data sheets for ordering the radiation-improved version if available.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
UC1845A-SP CDIP/JG (8) 6.67 mm × 9.60 mm
LCCC/FK (20) 8.89 mm × 8.89 mm
CFP/HKU (10) 6.48 mm × 7.02 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.