SLUSD37E
October 2017 – November 2019
UCC28056
PRODUCTION DATA.
1
Features
2
Applications
3
Description
No Load Power
Device Images
Simplified Application
4
Revision History
5
Device Comparison Tables
6
Pin Configuration and Functions
Pin Functions
7
Specifications
7.1
Absolute Maximum Ratings
7.2
ESD Ratings
7.3
Recommended Operating Conditions
7.4
Thermal Information
7.5
Electrical Characteristics
7.6
Typical Characteristics
8
Detailed Description
8.1
Overview
8.2
Functional Block Diagram
8.3
Feature Description
8.3.1
CrM/DCM Control Principle
8.3.2
Line Voltage Feed-Forward
8.3.2.1
Peak Line Voltage Detection
8.3.3
Valley Switching and CrM/DCM Hysteresis
8.3.3.1
Valley Delay Adjustment
8.3.4
Transconductance Amplifier with Transient Speed-up Function
8.3.5
Faults and Protections
8.3.5.1
Supply Undervoltage Lockout
8.3.5.2
Two Level Over-Current Protection
8.3.5.2.1
Cycle-by-Cycle Current Limit Ocp1
8.3.5.2.2
Ocp2 Gross Over-Current or CCM Protection
8.3.5.3
Output Over-Voltage Protection
8.3.5.3.1
First Level Output Over-Voltage Protection (Ovp1)
8.3.5.3.2
Second Level Over-Voltage Protection (Ovp2)
8.3.5.4
Thermal Shutdown Protection
8.3.5.5
Line Under-Voltage or Brown-In
8.3.6
High-Current Driver
8.4
Controller Functional Modes
8.4.1
Burst Mode Operation
8.4.2
Soft Start
9
Application and Implementation
9.1
Application Information
9.2
Typical Application
9.2.1
Design Requirements
9.2.2
Detailed Design Procedure
9.2.2.1
Custom Design With WEBENCH® Tools
9.2.2.2
Power Stage Design
9.2.2.2.1
Boost Inductor Design
9.2.2.2.2
Boost Switch Selection
9.2.2.2.3
Boost Diode Selection
9.2.2.2.4
Output Capacitor Selection
9.2.2.3
ZCD/CS Pin
9.2.2.3.1
Voltage Spikes on the ZCD/CS pin Waveform
9.2.2.4
VOSNS Pin
9.2.2.5
Voltage Loop Compensation
9.2.2.5.1
Plant Model
9.2.2.5.2
Compensator Design
9.2.3
Application Curves
10
Power Supply Recommendations
11
Layout
11.1
Layout Guidelines
11.1.1
VOSNS Pin
11.1.2
ZCD/CS Pin
11.1.3
VCC Pin
11.1.4
GND Pin
11.1.5
DRV Pin
11.1.6
COMP Pin
11.2
Layout Example
12
Device and Documentation Support
12.1
Custom Design With WEBENCH® Tools
12.2
Receiving Notification of Documentation Updates
12.3
Community Resources
12.4
Trademarks
12.5
Electrostatic Discharge Caution
12.6
Glossary
13
Mechanical, Packaging, and Orderable Information
7.3
Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
NOM
MAX
UNIT
VCC
Input voltage
12
V
T
A
Operating ambient temperature
-40
125
°C