TI公司的ucc28180是可編頻率（18 kHz到250 kHz）連續導電模式（CCM）功率因速修正（PFC）控制器，8引腳封裝，通用AC輸入，工作在100W 到幾kW范圍，主要用在服務器和臺式計算機電源，白色家電（空調器，冰箱），工業電源和平板（PDP，LCD和LED）TV等。本文介紹了UCC28180主要特性，功能框圖，典型應用電路圖以及230-V， 3.5-kW PFC效率大于98%參考設計TIDA-00779主要特性，系統指標，電路圖和材料清單。

The UCC28180 is a flexible and easy-to-use， 8-pin，active Power-Factor Correction （PFC） controller thatoperates under Continuous Conduction Mode （CCM）to achieve high Power Factor， low current distortionand excellent voltage regulation of boost preregulatorsin AC - DC front-ends. The controller issuitable for universal AC input systems operating in100-W to few-kW range with the switching frequencyprogrammable between 18 kHz to 250 kHz， toconveniently support both power MOSFET and IGBTswitches. An integrated 1.5-A and 2-A （SRC-SNK）peak gate drive output， clamped internally at 15.2 V（typical）， enables fast turn-on， turn-off， and easymanagement of the external power switch without theneed for buffer circuits.

Low-distortion wave shaping of the input currentusing average current mode control is achievedwithout input line sensing， reducing the externalcomponent count. In addition， the controller featuresreduced current sense thresholds to facilitate the useof small-value shunt resistors for reduced powerdissipation， especially important in high-powersystems. To enable low current distortion， thecontroller also features trimmed internal current loop regulation circuits for eliminating associatedinaccuracies.

Simple external networks allow for flexible compensation of the current and voltage control loops. In addition，UCC28180 offers an enhanced dynamic response circuit that is based on the voltage feedback signal to deliverimproved response under fast load transients， both for output overvoltage and undervoltage conditions. Anunique VCOMP discharge circuit provided in UCC28180 is activated whenever the voltage feedback signalexceeds VOVP_L thus allowing a chance for the control loop to stabilize quickly and avoid encountering theovervoltage protection function when PWM shutoff can often cause audible noise. Controlled soft start graduallyregulates the input current during start-up and reduces stress on the power switches. Numerous system-levelprotection features available in the controller include VCC UVLO， peak current limit， soft overcurrent， outputopen-loop detection， output overvoltage protection and open-pin detection （VISNS）。 A trimmed internal referenceprovides accurate protection thresholds and regulation set-point. The user can control low-power standby modeby pulling the VSENSE pin below 0.82 V.

UCC28180主要特性：

1? 8-Pin Solution （No AC Line Sensing Needed）

? Wide Range Programmable Switching Frequency（18 kHz to 250 kHz for MOSFET and IGBT-basedPFC Converters）

? Trimmed Current Loop Circuits for Low iTHD

? Reduced Current Sense Threshold （MinimizesPower Dissipation in Shunt）

? Average Current-Mode Control

? Soft Over Current and Cycle-by-Cycle PeakCurrent Limit Protection

? Output Overvoltage Protection With HysteresisRecovery

? Audible Noise Minimization Circuitry

? Open Loop Detection

? Enhance Dynamic Response During OutputOvervoltage and Undervoltage Conditions

? Maximum Duty Cycle of 96% （Typical）

? Burst Mode for No Load Regulation

? VCC UVLO， Low ICC Start-Up （《 75 μA）

UCC28180應用：

? Universal AC Input， CCM Boost PFC Convertersin 100-W to Few-kW Range

? Server and Desktop Power Supplies

? White Good Appliances （Air Conditioners，Refrigerators）

? Industrial Power Supplies （DIN Rail）

? Flat Panel （PDP， LCD， and LED） TVs

圖1.UCC28180功能框圖

圖2.UCC28180典型應用電路圖

圖3.UCC28180設計案例電路圖

230-V， 3.5-kW PFC效率大于98%參考設計TIDA-00779

230-V， 3.5-kW PFC With 》98% Efficiency， Optimized for BOM and Size Reference Design

This reference design is a 3.5-kW， cost competitivePFC designed for room air conditioners and othermajor appliances. This reference design is acontinuous-conduction-mode （CCM） boost converterimplemented using TI’s UCC28180 PFC controllerprovided with all of the necessary built-in protections.

The hardware is designed and tested to pass surgeand EFT testing as per the IEC 61000 requirementsfor household appliances.

The key highlights of this reference design are：

? Provides a ready platform for front-end PFCs toaddress power level requirements for appliancesup to 3.5 kW

? Up to 98.6% peak converter efficiency under 230-Vinput enable a competitive high power density andsmall heat sink design

? Robust output supply protected for outputovercurrent， output overvoltage， and output

undervoltage conditions

參考設計TIDA-00779主要特性：

? High Efficiency of 》 98% Over Entire OperatingVoltage Range， Allowing a Smaller Heat Sink

? Wide Full Load Operating Input Range of 190-V to270-V AC

? High Power Factor 》 0.99 and 《 5% THD FromMedium-to-Full Load （50 to 100%）

? Up to 3.5-kW High Power Output to Cover Most ofSingle-Phase Input PFC Application

? 8-Pin PFC Solution （No AC Line Sensing Needed）Enable Very Simple Design

? Reduced Current Sense Threshold MinimizesPower Dissipation

? High Power Density for Smaller Dimension

? Robust Output Supply Protected for OutputOvercurrent， Output Overvoltage， and OutputUndervoltage Conditions

? Meets Requirements of EFT Norm IEC 6000-4-4and Surge Norm IEC 61000-4-5

? Simple Use PCB Form Factor （215 × 145 mm）

參考設計TIDA-00779應用：

? Room Air Conditioners

? Industrial AC/DC 》 480 W

? Single-Phase UPS

? Other Major Appliances

圖4.參考設計TIDA-00779外形圖

參考設計TIDA-00779系統指標：

圖5.PFC調節器框圖

圖6.參考設計TIDA-00779電路圖

參考設計TIDA-00779材料清單：