Adaptive Constant On-Time (D-CAPTM) Control Study in Notebook Applications (Rev. B)
The buck converter with adopted voltage mode, current mode, constant on-time control, and adaptive on-time control (D-CAP™ mode) are discussed in detail in terms of their control methods, and their transient performances. The advantages of the D-CAP mode applicable to the portable applications are presented based on this analysis. The jitter mechanism in the D-CAP mode is studied, and an improvement method is introduced. The comparison of the jitter performance is presented with TPS51124, which implemented the silicon solution of ramp compensation.