1.2.1 Key Insight

From above expressions, the ACOT loop contains one low-frequency pole from the 1/s term, a double pole from the output LC filter, and two zeros introduced by the ripple-injection and feed-forward networks. The first zero, ω_Z1, is mainly set by R_INJ and C_INJ, while the second zero, ω_Z2, is mainly set by R1 and C_FF. These zeros are important because they help compensate for the phase lag introduced by the output LC double pole and improve the phase margin near crossover frequency. Thus, proper placement of C_INJ, R_INJ and C_FF directly determines the stability and transient performance of the ACOT converter.