TPS61199 PWM Dimming Acoustic Noise

Hi Sir.

TPS61199, Why is the PWM dimming acoustic noise  when the duty 50% (PWM dimming Freq. 5~8KHz)?

The PWM dimming had acoustic noise from input cap. & boost inductor component around.  

To add input cap. or L inductance are can't solve it. So, how can it be solved? 

Johnsin Tao：

Hi输入电容适当加大，layout尽量靠近电感，功率电感饱和电流足够。如果这些确认没有问题，再确认一下输出输出电容。