In this paper, an efficient, fully-parallel network of programmable logic array (NPLA)-based realization of iterative decoders for structured LDPC codes is presented. The LDPC codes are developed in tandem with the underlying VLSI implementation technique, without compromising chip design constraints. The codes are based on a novel modification of array codes. This design methodology results in reduced routing congestion, a major problem in prior approaches. The operating power, delay and chip-size of the circuits are estimated, indicating that this implementation significantly outperforms presently used standard-cell based architectures. The described LDPC design method can accommodate widely different requirements, such as those arising from recording and wireless channel applications.