Patent attributes
An image forming apparatus according to this invention prevents adverse effects on peripheral circuits and speeds up data transfer by preventing a mutual interference among signals. In the image forming apparatus, a transfer controller which converts into a differential serial data pair (data+/−) multiplex data td [6:0] multiplexed from head data vd [7:0], a head control signal vctl [3:0], a data enable signal dten, and a control enable signal cten, converts as well a clock signal clk into a differential clock signal pair (clk+/−), and transfers those differential serial data pair and differential clock signal pair to an LED head via a cable. The LED head receives both of the differential serial data pair and the differential clock signal pair to separate those pairs into head data hd [7:0], head control signal hctl [3:0], and data transfer clock hclk.