SLUSDD4B
April 2019 – December 2020
UC1843B-SP
PRODUCTION DATA
1
Features
2
Applications
3
Description
4
Revision History
5
Pin Configuration and Functions
6
Specifications
6.1
Absolute Maximum Ratings
6.2
ESD Ratings
6.3
Recommended Operating Conditions
6.4
Thermal Information
6.5
Electrical Characteristics
6.6
Typical Characteristics
7
Detailed Description
7.1
Overview
7.2
Functional Block Diagram
7.3
Feature Description
7.3.1
UVLO
7.3.2
Reference
7.3.3
Totem-Pole Output
7.4
Device Functional Modes
8
Application Information Disclaimer
8.1
Application Information
8.2
Typical Application
8.2.1
Design Requirements
8.2.2
Detailed Design Procedure
8.2.2.1
Switching Frequency
8.2.2.2
Transformer
8.2.2.3
RCD Diode Clamp
8.2.2.4
Output Diode
8.2.2.5
Output Filter and Capacitor
8.2.2.6
Compensation
8.2.2.7
Sense Resistor and Slope Compensation
8.2.3
Application Curves
9
Power Supply Recommendations
10
Layout
10.1
Layout Guidelines
10.1.1
Feedback Traces
10.1.2
Input/Output Capacitors
10.1.3
Compensation Components
10.1.4
Traces and Ground Planes
10.2
Layout Example
11
Device and Documentation Support
11.1
Receiving Notification of Documentation Updates
11.2
Support Resources
11.3
Trademarks
11.4
Electrostatic Discharge Caution
11.5
Glossary
12
Mechanical, Packaging, and Orderable Information
1
Features
QML class V (QMLV) qualified, SMD 5962-86704
5962
R
8670412VYC:
Radiation hardness assurance (RHA) up to
100-krad(Si) total ionizing dose (TID)
Optimized for offline and DC-to-DC converters
Low start-up current (< 0.5 mA)
Trimmed oscillator discharge current
Automatic feed forward compensation
Pulse-by-pulse current limiting
Enhanced load response characteristics
Undervoltage lockout (UVLO) with hysteresis
Double-pulse suppression
High-current totem-pole output
Internally-trimmed bandgap reference
500-kHz operation
Low R
O
error amplifier