SLUAAJ0 February 2024 TPS51397A , TPS54308 , TPS54320 , TPS54350 , TPS54620 , TPS54622 , TPS54821 , TPS54824 , TPS563300 , TPS566231 , TPS566235 , TPS566238 , TPS568230 , TPS56C215 , TPS62933 , TPS62933F , TPS62933O
A components selection method for second stage filter is proposed in this application note to make sure converter stability. Three types of feedback network design to support second stage filter are introduced at first and the advantages of hybrid sensing feedback is highlighted. On the basis, the loop response of peak current mode converter with second stage filter is analyzed at first. Then the expressions of zeros and poles introduced by second stage filter and hybrid sensing are derived through small signal analysis. The stability design method and low ripple power design flow are further proposed. Finally, the proposed method is verified by experiments.