A design of OSD technology to overlap the characters and pictures in the TV signal based on FPGA controller is introduced in this paper . The data of overlapped characters and pictures are stored in the ROM of FPGA

the times are generated by FPGA inner logic circuit to control the switch of TV channels to finish the overlapping work. The design has the advantages of simple code framework

good expansibility

convenient changing the display position. The results that the circuit works stably

and character phase wobbles little

were testified by using the method which can be widedly used in the OSD field.