Abstract Based on the introduction of MAX038, we discussed the principle and the whole frame of the digital function signal generator. We described the control of the oscillatory frequent, amplitude and the digital display in detail. The generator can output three kinds of waves: sine wave, square wave, triangle wave. The range of frequence can be within 0.1Hz to 10 MHz. The maximum of amplitude can reach to VP = 5V. This text has exposition the micro-computer controls the D/A electric circuit of conversion realize the process. In D/A changing electric circuit adopt the 8 bit 4 channel come to realize. And it is to design it is that voltage0～2.5V to ±2.3V tansform circuit and design it is that voltage0～2.5V to current 2µA～750µA tansform circuit. Porentiometer AD5171 is adopted in the control of length. This chip is that I2C bus control way. This thesis have I2C bus read/write drive program and adopt LCD show the waveform, frequent, range, variable duty cycle of control interface production. This system supports key-control or computer-control modes.
Key words: function signal D/A single - chip microprocessor control digital display
