In 1983, Asahi Chemical Industry Co. and Asahi microsystems Inc. jointly established Asahi Kasei Microsystems, Inc., referred to as AKM company, in Japan. Since its inception, AKM has been committed to the development of large-scale semiconductor integrated circuits in the field of information and communication. AKM company has won credit in the industry by successfully developing CMOS based mixed signal integrated circuit. This innovation also greatly reduces the cost of producing this kind of integrated circuit and shows a good application prospect. At present, AKM company can provide a series of circuits including analog-digital mixed circuit IC for mobile communication equipment, a / D and D / a conversion circuit based on delta sigma self-tuning technology, large capacity memory IC with lossless compression and error correction technology, etc.