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Problem 3 (10 points) In peak current mode control of the dc-dc converter, , = 0.5 and the loop transfer function cross over frequency is: fc = 15KHz. At the crossover frequency, the magnitude of GPS (not dB value) is GPS(f=15KHz = 4 and phase of GPS/=15KHz) = -90 For a Phase Margin of 60, determine f: fp kc k 1+/0. G(S)= s 1+slo, phase boost Current PWM Power Controller IC Stage v (s) Va iz (s) G(S) sla i7(s)+ 1 (s) (6) Figure 6-5 PFC current loop. Problem 3 (10 points) In peak current mode control of the dc-dc converter, , = 0.5 and the loop transfer function cross over frequency is: fc = 15KHz. At the crossover frequency, the magnitude of GPS (not dB value) is GPS(f=15KHz = 4 and phase of GPS/=15KHz) = -90 For a Phase Margin of 60, determine f: fp kc k 1+/0. G(S)= s 1+slo, phase boost Current PWM Power Controller IC Stage v (s) Va iz (s) G(S) sla i7(s)+ 1 (s) (6) Figure 6-5 PFC current loop