函数发生器是一种用于产生波形等函数信号的电子测试设备，是一种重要的信号源。部分函数发生器还具有调制的功能，可以对输出的信号进行调幅、调频等附加功能。函数发生器被广泛应用于电路教学、电子器件的样品试验和批量生产的质量检测中。

A function generator is usually a piece of electronic test equipment or software used to generate different types of electrical waveforms over a wide range of frequencies. Some of the most common waveforms produced by the function generator are the sine, square, triangular and sawtooth shapes. These waveforms can be either repetitive or single-shot (which requires an internal or external trigger source). Integrated circuits used to generate waveforms may also be described as function generator ICs.