SLUSA71B
July 2010 – September 2025
UCC28070-Q1
PRODUCTION DATA
1
1
Features
2
Applications
3
Description
4
Pin Configuration and Functions
5
Specifications
5.1
Absolute Maximum Ratings
5.2
ESD Ratings
5.3
Recommended Operating Conditions
5.4
Thermal Information
5.5
Electrical Characteristics
5.6
Typical Characteristics
6
Detailed Description
6.1
Overview
6.2
Functional Block Diagram
6.3
Feature Description
6.3.1
Interleaving
6.3.2
Programming the PWM Frequency and Maximum Duty-Cycle Clamp
6.3.3
Frequency Dithering (Magnitude and Rate)
6.3.4
External Clock Synchronization
6.3.5
Multi-phase Operation
6.3.6
VSENSE and VINAC Resistor Configuration
6.3.7
VSENSE and VINAC Open-Circuit Protection
6.3.8
Current Synthesizer
6.3.9
Programmable Peak Current Limit
6.3.10
Linear Multiplier and Quantized Voltage Feed Forward
6.3.11
Enhanced Transient Response (VA Slew-Rate Correction)
6.3.12
Bias Voltages (VCC and VREF)
6.3.13
PFC Enable and Disable
6.3.14
Adaptive Soft-Start
6.3.15
PFC Start-Up Hold Off
6.3.16
Output Overvoltage Protection (OVP)
6.3.17
Zero-Power Detection
6.3.18
Thermal Shutdown
6.3.19
Current Loop Compensation
6.3.20
Voltage Loop Compensation
6.4
Device Functional Modes
7
Application and Implementation
7.1
Application Information
7.2
Typical Application
7.2.1
Design Requirements
7.2.2
Detailed Design Procedure
7.2.2.1
Output Current Calculation
7.2.2.2
Bridge Rectifier
7.2.2.3
PFC Inductor (L1 and L2)
7.2.2.4
PFC MOSFETs (M1 and M2)
7.2.2.5
PFC Diode
7.2.2.6
PFC Output Capacitor
7.2.2.7
Current-Loop Feedback Configuration (Sizing of the Current-Transformer Turns-Ratio NCT and Current-Sense Resistor RS)
7.2.2.8
Current-Sense Offset and PWM Ramp for Improved Noise Immunity
7.2.3
Application Curves
7.3
Power Supply Recommendations
7.4
Layout
7.4.1
Layout Guidelines
7.4.2
Layout Example
8
Device and Documentation Support
8.1
Documentation Support
8.1.1
Related Documentation
8.2
Receiving Notification of Documentation Updates
8.3
Support Resources
8.4
Trademarks
8.5
Electrostatic Discharge Caution
8.6
Glossary
9
Revision History
10
Mechanical, Packaging, and Orderable Information
1
Features
AEC-Q100 qualified for automotive applications:
Temperature grade 1, T
A
: –40°C to 125°C
Device HBM ESD classification level 2
Device CDM ESD classification level C4
Interleaved average current-mode PWM control with inherent current matching
Advanced current-synthesizer current sensing for superior efficiency
Synchronization capability to external clock
Highly-linear multiplier output with internal quantized voltage feed-forward for near-unity PF
Enhanced transient response through slew-rate correction of voltage amplifier output current
Programmable frequency (30kHz to 300kHz)
Programmable maximum duty-cycle clamp
Programmable frequency-dithering rate and magnitude (up to 30kHz) for EMI reduction
Programmable soft-start
Programmable peak current limiting
External PFC-disable interface
Protections: bias-supply UVLO, output overvoltage, open
‑
loop detection, open-circuit detection on VSENSE and VINAC,
and PFC-enable monitoring