Cross-Regulation-Suppression control scheme for CCM Single-Inductor-Dual-Output buck converter with ordered-power-distributive control

A Single-Inductor-Dual-Output (SIDO) buck converter with Cross-Regulation-Suppression (CRS) control scheme is presented. The converter operates in continuous-conduction-mode (CCM) and employs ordered-power-distributive control (OPDC) to distribute the inductor current to the two outputs. The novel CRS control method is used to suppress the cross-regulation (CR) of the SIDO which is an important issue in OPDC CCM converter design. On-chip type-III compensator is incorporated in the SIDO converter to eliminate off-chip components and accelerate system response. The CRS controlled converter is fabricated with AMS 0.35μm CMOS process and operates at 2MHz. Measurement results show that this converter achieves a cross-regulation down to 0.056mV/mA with 180mA load current changes and a response time less than 20μs. The maximum efficiency is 91.8%.