Dears,
After the bottom of the inductor is coated with plastic, the duty cycle of the SW output waveform decreases from 25% to 5%, resulting in heat;
The customer's power supply is used in a variety of products. In one product, the bottom of the inductance will be coated with plastic to prevent the inductance from falling off. The output duty cycle of about 50% SW pin will become smaller, resulting in IC heating. After the inductor is re-welded and the bottom plastic is removed, the SW output is normal;