Monolithic quasi-sliding-mode controller for SIDO buck converter with a self-adaptive free-wheeling current level

An analog implementation of a novel fixed-frequency quasi-sliding-mode controller for single-inductor dual-output（SIDO） buck converter in pseudo-continuous conduction mode（PCCM） with a self-adaptive freewheeling current level（SFCL） is presented.Both small and large signal variations around the operation point are considered to achieve better transient response so as to reduce the cross-regulation of this SIDO buck converter.Moreover,an internal integral loop is added to suppress the steady-state regulation error introduced by conventional PWM-based sliding mode controllers.Instead of keeping it as a constant value,the free-wheeling current level varies according to the load condition to maintain high power efficiency and less cross-regulation at the same time.To verify the feasibility of the proposed controller,an SIDO buck converter with two regulated output voltages,1.8 V and 3.3 V,is designed and fabricated in HEJIAN 0.35 m CMOS process.Simulation and experiment results show that the transient time of this SIDO buck converter drops to 10 s while the cross-regulation is reduced to 0.057 mV/mA,when its first load changes from 50 to 100 mA.

Developing a Super-lift Luo-converter with Integration of Buck Converters for Electric Vehicle Applications

In this paper,a DC-DC multi-port converter is introduced by integrating a super-lift and a buck converter(SLBC).The proposed single-input dual-output(SIDO)converter has conventional positive output voltage super-lift advantages while simultaneously generating a step・up voltage by Luo・converter and a step-down voltage by the buck converter.In this structure,without utilizing electromagnetic components to generate a dual output,the ripple in output voltages is kept low.Meanwhile,the introduced SLBC has a simple structure and an appropriate control method providing a wide range of output voltages.Besides,to illustrate the advantages of the proposed SIDO converter,a comparison with other similar configurations is carried out.Also,simulation and experiment results indicate a considerable reduction in conduction losses compared to other SIDO converters in the same situations.The operation accuracy of SLBC is validated by performing several simulations in PSCAD/EMTDC software and testing a 150W prototype in the laboratory.