Inrush-Current Limiting and Soft-Switching Techniques for Filament Light Source Regulator

Inrush-current limiting voltage regulators are considered important components in many voltage and current drivers applications, to reduce the startup surge of current from the voltage supply to the supplied loads. Moreover, driving stable current to multiple filament light sources is necessary to improve their life-time and reduce light fluctuations. In this paper, a fully-integrated soft-start linear voltage regulator is proposed, for driving high current to filament light sources. In addition to the soft startup feature, this proposed technique is used to allow introducing new loads during operation without disturbing the regulated output. The design has been implemented in 130nm technology. The maximum driving current is 1.5A from 5V supply. Minimum drop-out voltage of 250mV is used to supply different filament light sources.