Adaptive Dead-Time-Controlled Boost Converter With Startup Voltage Lower Than Threshold

Recently,wireless sensor network(WSN)is a new field that more and more researchers are interested in.Wireless sensor network includes harvesting and managing the energies from the network,then collecting information and communicating with the outside networks by the energies harvested before.The energies harvested from wireless sensor network is so poor and unstable that they can't directly supply to other circuits.A Boost converter is of great demand to manage these energies and output a constant voltage.So this paper proposed a Boost converter to manage the energies in wireless sensor network.Firstly,the basic theory of the Boost converter is introduced.Secondly,the small signal model,stability analysis and compensation networks design are addressed.Thirdly,this paper offer the key blocks of the Boost converter,including the low voltage start up block,the feed forward block,the adaptive dead time block,the bandgap reference,the oscillator,the error amplifier and so on.The energies harvested is stored in a capacity by the rectifiers which is used as the input voltage of the Boost converter.The input voltage of the Boost converter may be very low(a few hundred millivolts)since the energies harvested may be poor.In order to start up and work stably in such a low voltage,a low voltage start up block is designed in the Boost converter.The energies harvested is variable that the input voltage is variable too.A feed forward block is designed to reduce the line transient of the converter,so that the converter is able to respond to the change of the input voltage rapidly and work stably.Besides,an adaptive dead time block is prosed in this paper to enhance the converting efficiency of the Boost converter.The blocks mentioned before are introduced in detail in this paper.Finally,based on SMIC 0.18?m Mixed signals CMOS technology platform,this paper completes the simulation and the layout of the presented Boost converter.According to the simulation results,the proposed Boost converter is able to start up in 320 m V input voltage.Thanks to the feed forward method,4% of the line transient of the Boost converter is reduced,compared with the traditional Boost converter.Besides the peak efficiency can be up to 92.1% by the adaptive dead time method.As seen from the simulation results,the proposed Boost converter meets the design objective and is suitable for wireless sensor network.