Abstract: Quasi-cyclic low-density parity-check (QC-LDPC) codes have been adopted as the inner code of channel codes in chinese digital terrestrial television broadcasting standard (CDTTB). These code have encoding advantage over other types of LDPC codes. Based on its systematic circulant form, this paper presents an encoder with semi-parallel and pipeline architectures. The encoding of LDPC codes at multiple rates can be achieved in transmitter. With carefully designing the involved reqisters and fully multiplexing the hardware, resources are reduced on the premises that the payload rates are met. This architecture has been implemented and its functionality verified.