A touch screen controller (TSC) includes: a front end circuit configured to send a control signal to a touch panel and to receive a touch signal from the touch panel; an algorithm processing circuit configured to process source data generated based on the touch signal according to a predetermined algorithm; a memory configured to store the source data and result data obtained as a result of processing the source data at the algorithm processing circuit; and a bus configured to transfer data among the front end circuit, the algorithm processing circuit, and the memory. The algorithm processing circuit includes: a buffer configured to temporarily store the source data or the result data and shared by at least two circuits; and a special function register (SFR) configured to store a setting value necessary for an operation of the algorithm processing circuit.