针对低频信号源进行设计，设计以LPC2138为控制芯片，探索研究了低频信号发生器的原理和应用，设计输出频率及幅度可调，频率范围为1HZ～50KHZ的正弦波、方波、三角波、调幅波、调频波及其复合波信号，具有信号频率、波形、幅度变化容易，硬件简单可靠等特点的多功能信号源-Design, design for low-frequency signal source to LPC2138 controller chip, and explore the principles and applications of low-frequency signal generator, the design output frequency and amplitude adjustable frequency range is 1HZ to 50KHZ sine wave, square wave, triangle wave, AMwaves, FM waves and their composite wave signal, the signal frequency, waveform, amplitude changes in hardware and easy, simple and reliable multi-function source