Control-to-output and duty ratio-to-inductor current transfer functions of peak current-mode controlled dc-dc PWM buck converter in CCM

The control-to-output and the duty ratio-to-inductor current transfer functions of peak current-mode controlled PWM dc-dc buck converter in CCM are derived and illustrated. The closed inner-current loop and the power stage inductor current-to-output voltage transfer functions are used to derive the control-to-output transfer function of the peak current-mode controlled buck converter in CCM, which is essential for the outer-voltage loop controller design. A small-signal model including parasitic components and delay is used to derive the power stage transfer function, necessary for proper analysis of the power stage. The loop gain of the inner-current loop is derived and is shown that it is independent of converter topology.