设置
快速交货
免运费
国际贸易术语
支付类型
市场产品
After an appropriate Buck converter IC has been selected, the rest of the external components also need to be selected in order for the Buck converter to work properly. First, the inductor. Here are some basic guidelines for selecting an inductor for most applications. Take the switching frequency of the device and use the top equation here to derive a recommended value for the inductor. For faster load transients, use a lower inductance. For lower switching loss and lower voltage ripple, use a higher inductance. As a rule of thumb, it is recommended that ΔIL, the inductor current ripple, be approximately 30% to 40% of the rated maximum load current in Peak Current Mode designs, and 30% to 50% in Constant On-time designs. These inductor current ripple ranges are a good trade-off between load transient response and AC losses. The peak current, IPEAK, determines the required saturation current rating, which influences the size of the inductor. Saturating the inductor decreases the converter efficiency while increasing the temperatures of both the inductor and the internal power MOSFETs. Therefore, choosing an inductor with the appropriate saturation current rating is important. For most applications, it is recommended to select an inductor with a DC current rating of at least 35% higher than the maximum load current for margin.
