Small-signal modeling technique fails in capturing operating point variation in a dc-dc converter model. A sample average current mode controller design is used to highlight this difficulty for a time-varying voltage reference tracking problem. Sliding mode controller design based on the large signal model of the system is studied as an alternative for such problems. A sliding surface consisting of both voltage and current error is presented based on the discrete time state-space model of the system. Simulation and experimental results validate the performance of sliding mode controller in a boost converter for tracking sinusoidal and triangular voltage reference signals. The performance of the system under load variations is also presented. © 2016 IEEE.