Abstract
Abstract Nowadays, handheld devices with small LCD panel for information display have become very popular, they have advantage of small size and low-power. The application of small LCD panel has extended to different areas such as PDA, mobile phone, GPS, camera and TV game. In new technology, by embedded phototransistors, the panel can also be used as an image input device. In this study we investigate the design of interface circuit for this dual purposes application and do the implementation in an OMAP environment. The interface circuit is suitable for low-power standard LCD panel too. OMAP environment provides a reliable microcontroller function for the interface circuit design. By the study the panel light-pen input signal can be accessed and processed in the AMR processor.