Fairchild公司的192W LCD TV电源方案采用FSFR系列器件FSFR2100,额定输出功率192W,输出电压24V/8A,输入电压400V,效率大于94%,具有多种保护功能以增加系统可靠性.本文介绍了FSFR2100的主要特性,功能方框图, LLC谐振半桥转换器典型应用电路以及FSFR2100评估板电路图和材料清单(BOM).
The FSFR-series are a highly
integrated power switches designed for high-efficiency half-bridge resonant
converters. Offering everything necessary to build a reliable and robust resonant
converter, the FSFR-series simplifies designs and improves productivity, while improving performance. The FSFR-series combines power MOSFETs
with fast-recovery type body diodes, a high-side gate-drive
circuit, an accurate current
controlled oscillator, frequency limit
circuit, soft-start, and built-in protection functions. The high-side gate-drive
circuit has a common-mode noise cancellation capability, which guarantees stable operation
with excellent noise immunity. The fast-recovery body diode
of the MOSFETs improves reliability against abnormal operation conditions, while minimizing the effect of the reverse recovery. Using the zero-voltage-switching (ZVS)
technique dramatically reduces the switching losses and efficiency is significantly improved. The ZVS also reduces the switching noise noticeably, which allows a
small-sized Electromagnetic Interference (EMI) filter.
The FSFR-series can be applied to various resonant
converter topologies such as series resonant, parallel resonant, and LLC resonant converters.
FSFR2100主要特性:
Variable Frequency Control
with 50% Duty Cycle for Half-bridge Resonant Converter Topology
High Efficiency through Zero Voltage Switching (ZVS)
Internal SuperFETs with Fast-Recovery Type Body Diode (trr=120ns) for FSFR2100 and UniFETs with Fast-Recovery Type Body Diode (trr<160ns) for FSFR2000/1900/1800/1700.
Fixed Dead Time (350ns) Optimized for MOSFETs
Up to 300kHz Operating Frequency
Pulse Skipping for Frequency Limit (Programmable) at Light-Load Condition
Remote On/Off Control Using Control Pin
Protection Functions: Over-Voltage Protection (OVP), Over-Load Protection (OLP), Over-Current Protection (OCP), Abnormal Over-Current Protection (AOCP), Internal Thermal Shutdown (TSD)
FSFR2100应用:
PDP and LCD TVs
Desktop PCs and servers
Adapters
Telecom Power Supplies
Audio Power Supplies
图1.FSFR2100方框图
图2.典型应用电路图(LLC谐振半桥转换器)
图3.FSFR2100评估板电路图(LCC谐振转换器)
材料清单(BOM):
