Integrated circuit board according to its function, structure, can be divided into analog integrated circuit board and digital two categories.

Simulation is used to generate, amplify, and process a variety of analog signals (signals whose amplitude varies with the time boundary). For example, the audio signal of a semiconductor radio, the tape signal of a video recorder, etc.), and the digital is used to generate, amplify and process various digital signals (referring to signals with discrete values in time and amplitude. Such as VCD, DVD playback of audio signals and video signals).