This paper presents a 2-MHz voltage-mode controlled buck converter with fast reference-tracking responses. An analog-controlled hybrid scheme with end-point prediction technique is proposed to achieve nearly optimum reference tracking process with resistor load under different tracking conditions. The converter is designed in a 0.18-μm standard CMOS process. With a constant load resistor of 4Ω, the simulated up and down tracking speeds are 0.3 μs/V and 0.245 μs/V, respectively.