The UTC 1812A/1812B/1813 is a CMOS LSI chip designed for use in sound effect products .It is equipped with tone circuit, noise circuit and other control logic to generate different sounds including rifle gun, machine gun, booming sound, door bell, alarm etc. The customer supplied sound source can be analyzed and programmed into an internal ROM by changing a mask layer during device fabrication. The UTC 1812A/1812B/1813 is suitable for various toy applications.