Design On Car Sound Device System

With the development of technology, electrical product is an important part of modern people life. The requirement of electrical product is more and more. For electronically consumable product used by population, besides function requirement, cost is a critical parameter. To be winner in price competition in auto wireless product market, we must integrate more function on smaller area so that we can get less cost in material. So in this project I design a high frequency precision tuner which integrated PLL function into the original turner.Automatic ambulant radio is more complicated than family immobile radio due to the automatic motility. Some technical obstruction will be made due to the reflection by high building and high mountain. These special chip can lighten the affect from disturb signal and ensure the receiver quality in the automatic.In the process of research, design, execution and test of this project, author emphasized the PLL related circuit design and complete flow chart and circuit diagram, chip selection, sample making and testing. Compatibility and timbre quality are all improved, and we performed combination of theory research and actual application.