Fairchild公司的FAN9611/12是交叉雙路邊界導通模式(BCM) PFC控制器,控制輸出功率從300W到大于800W,允許使用較便宜二極管而不犧牲效率,由于波紋電流相互抵消和開關頻率的加倍,使得輸入和輸出濾波器更小,主要用在100-1000W AC/DC電源,大屏幕LCD-TV,PDP-TV,PR-TV電源,高效臺式計算機和服務器電源以及太陽能微逆變器.本文介紹了FAN9611/12主要特性,方框圖,典型應用電路圖,以及300W交叉雙路BCM小尺寸PFC評估板主要特性,電路圖,材料清單和PCB元件布局圖.
The FAN9611/12 family of interleaved dual Boundary-Conduction-Mode (BCM) Power-Factor-Correction (PFC) controllers operate two parallel-connected boost power trains 180° out of phase. Interleaving extends the maximum practical power level of the control technique from about 300W to greater than 800W. Unlike the continuous conduction mode (CCM) technique often used at higher power levels, BCM offers inherent zerocurrent switching of the boost diodes, which permits the use of less expensive diodes without sacrificing efficiency. Furthermore, the input and output filters can be smaller due to ripple current cancellation and effective doubling of the switching frequency.
The converters operate with variable frequency, which is a function of the load and the instantaneous input /output voltages. The switching frequency is limited between 16.5kHz and 525kHz. The Pulse Width Modulators (PWM) implement voltage-mode control with input voltage feedforward. When configured for PFC applications, the slow voltage regulation loop results in constant on-time operation within a line cycle. This PWM method, combined with the BCM operation of the boost converters, provides automatic power factor correction.
The controllers offers bias UVLO (10V / 7.5V for FAN9611 and 12.5V / 7.5V for FAN9612), input brownout, over-current, open-feedback, output overvoltage, and redundant latching over-voltage protections.
Furthermore, the converters’ output power is limited independently of the input RMS voltage. Synchronization between the power stages is maintained under all operating conditions.
FAN9611/12主要特性:
Sync-Lock™ Interleaving Technology for 180° Out-of-Phase Synchronization Under All Conditions
Automatic Phase Disable at Light Load
Dead-Phase Detect Protection
2.0A Sink, 1.0A Source, High-Current Gate Drivers
High Power Factor, Low Total Harmonic Distortion
Voltage-Mode Control with (VIN)2 Feedforward
Closed-Loop Soft-Start with User-Programmable Soft-Start Time for Reduced Overshoot
Minimum Restart Frequency to Avoid Audible Noise
Maximum Switching Frequency Clamp
Brownout Protection with Soft Recovery
Non-Latching OVP on FB Pin and Latching Second-Level Protection on OVP Pin
Open-Feedback Protection
Power-Limit and Current Protection for Each Phase
Low Startup Current of 80μA Typical
Works with DC and 50Hz to 400Hz AC Inputs
FAN9611/12主要應用:
100-1000W AC-DC Power Supplies
Large Screen LCD-TV, PDP-TV, RP-TV Power
High-Efficiency Desktop and Server Power Supplies
Networking and Telecom Power Supplies
Solar Micro Inverters
圖1.FAN9611/12方框圖
圖2.FAN9611/12典型應用電路圖
圖3.FAN9611/12交叉BCM PFC應用電路圖
FAN9611 300W交叉雙BCM小尺寸PFC評估板
This FAN9611 evaluation board uses a four-layer Printed Circuit Board (PCB) designed for 300W (400V/0.75A) rated power. The maximum rated power is 350W and the Maximum On-Time (MOT) power limit is set to 360W. The FEBFAN9611_S01U300A is optimized to demonstrate all the FAN9611 efficiency and protection features in a lowprofile height form factor less than 18mm.
FAN9611 300W評估板主要特性:
180° Out-of-Phase Synchronization
Automatic Phase Disable at Light Load
1.8A Sink, 1.0A Source, High-Current Gate Drivers
Transconductance (gM) Error Amplifier for Reduced Overshoot
Voltage-Mode Control with (VIN)2 Feed-Forward
Closed-Loop Soft-Start with Programmable Soft-Start Time for Reduced Overshoot
Minimum Restart Timer Frequency to Avoid Audible Noise
Maximum Switching Frequency Clamp
Brownout Protection with Soft Recovery
Non-Latching OVP on FB Pin and Second-Level Latching Protection on OVP Pin
Open-Feedback Protection
Over-Current and Power-Limit Protection for Each Phase
Low Startup Current: 80μA Typical
Works with DC input or 50Hz to 400Hz AC Input
圖4.FAN9611 300W評估板外形圖:尺寸152mm x 105mm
FAN9611 300W評估板指標:
圖5.FEBFAN9611_S01U300A 300W評估板電路圖
圖6.浪涌電流限制電路
300W評估板材料清單:
圖7.300W評估板PCB元件布局圖:頂層
圖8.300W評估板PCB元件布局圖:底層 |
