Signal generator, also known as signal source or oscillator, it includes arbitrary waveform generators which has a wide range of applications in the field of production practice and technology. Various waveform curves can be represent by trigonometric equations .It can produce a variety of waveforms, such as triangular, sawtooth, rectangular (including square wave), sine wave circuit is called the function of signal generator. Function generator has a very wide range uses in circuit testing and equipment testing. For example, in the communications,broadcasting and television systems, radio frequency (high frequency) emission is required. The radio frequency wave is a carrier wave. To carry audio (low frequency), video signal or pulse signal, an oscillator capable of generating high frequency is needed.