A Multi-Path LED Driver Circuit with Serial Structure by using Protection Circuits

Abstract

The LED is attracting attention in lighting market as advantages such as long life and low power consumption. As a LED has a limitation on the brightness per cell, multiple LEDs are used. Therefore, the multi-path consisting of several LEDs is used variously depending on the application. There are parallel and serial connections in multiple output LED. The brightness and quality of LED module are affected by current, and parallel configuration has a disadvantage of current matching. However, the parallel connection has a advantage that remaining LEDs are turned on , even though some LEDs are out of order. The serial configuration has a advantage of accurate current matching. However, the serial configuration has a disadvantage that whole LEDs are turned off, even though one LED is out of order. This paper proposes a multi-path LED driver circuit including the protection circuit. The proposed circuit has the advantages of the serial connection, and overcomes the disadvantages of the serial connection with the protection circuit. To verify the performance of the proposed circuit, simulation and experimental results were carried out.