FairchildFAN6920MR臨界模式PFC電源解決方案

Fairchild公司的FAN6920MR是采用mWSaver技術的集成了臨界模式PFC控制器和準諧振電流模式PWM控制器,提供了成本效益的設計和降低了外接元件. FAN6920MR具有谷低檢測,綠色模式工作以及高/低火線電壓超功率補償,從而提高了電源系統的性能,主要用在筆記本電腦適配器,開架開關電源和電池充電器.本文介紹了FAN6920MR主要特性,方框圖, 典型應用電路圖, 設計案例最終電路圖,材料清單和PCB布局考慮.

FAN6920MR: mWSaver? Technology Integrated Critical-Mode PFC and Quasi-Resonant Current-Mode PWM Controller

Factor Correction (PFC) controller and quasi-resonant PWM controller. Integration provides cost-effective design and reduces external components.

For PFC, FAN6920MR uses a controlled on-time technique to provide a regulated DC output voltage and to perform natural power-factor correction. With an innovative THD optimizer, FAN6920MR can reduce input current distortion at zero-crossing duration to
improve THD performance.

For PWM, FAN6920MR provides several functions to enhance the power system performance: valley detection, green-mode operation, and high / low line over-power compensation. Protection functions include secondary-side open-loop and over-current with autorecovery protection; external auto-recovery triggering; adjustable over-temperature protection by RT pin; and external NTC resistor, internal over-temperature shutdown, VDD pin OVP, and DET pin over-voltage for output OVP, and brown-in / out for AC input voltage UVP.

The FAN6920MR controller is available in a 16-pin small-outline package (SOP).

FAN6920MR主要特性:

? Integrated PFC and Flyback Controller

? Critical-Mode PFC Controller

? Zero-Current Detection for PFC Stage

? Quasi-Resonant Operation for PWM Stage

? Internal Minimum 5μs tOFF for QR PWM Stage

? Internal 5ms Soft-Start for PWM

? Brownout Protection

? High / Low Line Over-Power Compensation

? Auto-Recovery Over-Current Protection

? Auto-Recovery Open-Loop Protection

? Externally Auto-Recovery Triggering (RT Pin)

? Adjustable Over-Temperature Protection

? VDD Pin and Output Voltage OVP (Auto-Recovery)

? Internal Over-Temperature Shutdown (140°C)

FAN6920MR應用:

? AC/DC NB Adapters

? Open-Frame SMPS

? Battery Charger

圖1.FAN6920MR方框圖

圖2.FAN6920MR典型應用電路圖

圖3.FAN6920MR設計案例最終電路圖

圖4. 設計案例布局考慮
設計案例材料清單: