Drivers for OLEDs

Organic light emitting diodes (OLEDs) are expected to become important light sources in the future. In contrast to point source inorganic LEDs, OLEDs are large area device. This in combination with different materials results in differences in performance and electrical behaviour, which on their turn result in different drivers. This work gives an overview of OLED characteristics. Based on these characteristics a simplified equivalent circuit is obtained and driver requirements are derived. It is found that AM dimming is preferred. Additionally, some OLED characteristics are compared with those of inorganic LEDs.