Publication: Design a white led driver with controlled by pulse width modulation technique
Loading...
Date
2007-05-01
Authors
Ng, Shyue Lie
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
In the undergraduate project, I was assigned a project title white LED driver. It is used to convert a low input voltage to a high output voltage. This circuit drives as many as four white LEDs in series from a 2.5V to 5.5V source and the LED current from 3mA to 80mA. The output voltage must enough to drives all LEDs to luminate, and maximum output voltage is 16V. A signal is used to trigger the MOSFET switch by using an external signal with frequency 1MHz. In this thesis, it will cover the application of white LED driver (also can called as boost converter). Besides that, it also include the step of design this project and the relevant theories. Pulse Width Modulation technique has been used to drives the output voltage to higher voltage. Based on specification, a white LED driver use power MOSFET as the switch. In order to trigger the MOSFET, a switching circuit with high frequency was designed based on Pulse Width Modulation (PWM) technique. The simulations and analysis was done by using Orcad and the design of the prototype circuit was tested to get the data. As a conclusion, I need to design a white LED driver circuit include control duty cycle of switching signal to drive an input voltage ranged 2.5V to 5.5V source to an output voltage with maximum 16V by using Pulse Width Modulation technique.