
我把4.2V电压升压为5.0V的,开关频率2.3MHZ,电感总能听到嘶嘶的省下的,这是属于正常的吗?\

zhiwen cheng1:
回复 KW X:
Vout=Vfb*(1+R1/R2)
To minimize the current through the feedback divider network, R2 should be between 180 kΩ and 360 kΩ. The sum of R1 and R2 should not exceed ~1 M?, to keep the network robust against noise. For the example, R1 is 768 kΩ and R2 is 243 kΩ. An external feed forward capacitor C1 is required for optimum load transient response. The value of C1 should be 100 pF. The connection from the FB pin to the resistor divider should be kept short and away from noise sources, such as the inductor or the SW line.
要求R2=180~360K
zhiwen cheng1:
回复 KW X:
上升和下降波形有些重影的。
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