Fairchild 公司的FAN6754B是高度集成的绿色模式PWM控制器,能提高反激转换器的性能,最小化待机功耗.高压起动,低工作电流1.5mA,固定PWM频率65kHz,频率跳频以降低EMI,峰值电流模式控制,主要用在LCD监视器,LCD TV和笔记本电脑.本文介绍了FAN6754B主要特性,功能方框图,典型应用电路图以及65W(19V / 3.42A)反激转换器的主要指标,电路图,材料厂清单和PCB布局图.
FAN6754B: Highly Integrated Green- Mode PWM Controller
The highly integrated FAN6754B PWM controller provides several features to enhance the performance of flyback converters. To minimize standby power consumption, a proprietary green-mode function provides off-time modulation to continuously decrease the switching frequency under light-load conditions.
Under zero-load and very light-load conditions, FAN6754B saves PWM pulses by entering deep burst mode. This burst mode function enables the power supply to meet international power conservation requirements.
FAN6754B integrates a frequency-hopping function internally to reduce EMI emission of a power supply with minimum line filters. Built-in synchronized slope compensation is accomplished by proprietary HV monitor to adjust VLimit for constant output power limit over universal AC input range. The gate output is clamped at 13V to protect the external MOSFET from over-voltage damage.
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