LED technologies in energy efficient applications

In this thesis, a quarter part of 21? LCD backlight is done with rgb leds. The thesis consists of designing and analyzing the power board, the driver board and the led board. For the power board the buck converter topology has chosen for easy implementation and a microcontroller 16F877 was used to generate pwm signal for the mosfet. Using microcontroller makes the system more stable according to analog circuits.The most important thing is the heat, that the driver IC?s (TLC5941 in this thesis) generate when there is excess voltage on them. The microcontroller is also used to prevent the IC from this voltage. The driver IC?s requires control signals, to determine the current value and the brightness of leds. These control signals generated with another 16F877.Simulations are carried on Proteus ISIS 7. The application software is converted from Pic Basic Pro into hex files. The system pcb design was done with Proteus ARES 7.At last the consuming energy was measured and compared with the same size of CCFL backlight TV.