6 Conclusion

This application note analyzes the effect of switching frequency on the performance of buck converter. The higher the switching frequency, the smaller inductor and capacitor are needed, and a better dynamic performance can be achieved while it decreases the efficiency with the increase of switching frequency.

Table 6-1 summarizes the bench test results at both 600-kHz and 1000-kHz using the TPS568230. The device under 1000kHz mode can be paired with a smaller filter inductor and output capacitor. It can improve the ripple and load transient performance in this condition. With the increase of power loss under 1000kHz mode, the efficiency becomes lower then 600kHz mode. There is a trade-off between dynamic performance and efficiency. The engineer can choose 600kHz mode if they care more about efficiency, otherwise, 1000kHz mode is a better choice to achieve better dynamic performance.