An Input-Adaptive Self-Oscillating Boost Converter for Fault-Tolerant LED Driving With Wide-Range Ultralow Voltage Input

An input-adaptive self-oscillating boost converter is proposed for wide-range ultralow voltage input LED driving with tight input regulation, low cost, high efficiency, and high reliability. It consists of a self-oscillation unit, a rectification unit, and an input-adaptive peak-current control unit with a blanking time control branch and an open-circuit protection branch. In this paper, its operation principle including an input-adaptive peak-current control scheme with a blanking time control strategy and a method to provide multiple protection functions is introduced. For experimental verification, a prototype boost converter was implemented by using several commonly used cheap components and devices. The steady-state and dynamic results obtained in the experiments show that it could start up successfully by itself, could operate with tight input regulation and high efficiency, and had short-circuit and open-circuit fault-tolerant characteristics.