Generator. - Here is Electronic Project : DDS Function Generator using ATMEGA16. This is a new implementation of the AVR DDS signal generator v2.0, already published in scienceprog.com. It is obvious that full credit for the original schematic and the firmware goes to its original creator. Presented here is a different PCB that is compact, single sided with only through-hole components for easy construction.
The function generator features two BNC outputs : one for the high speed [1 to 8 MHz] square signal (BNC1) and another for the DDS signal (BNC2). Offset and amplitude can be regulated by two potentiometers : offset in range of +5V to -5V (POT1) and amplitude in range of 0 to 10V (POT2). Up and down arrow buttons are used for changing the function type (sine, triangle etc.) while left and right arrow buttons are used for changing the frequency value. There is also a separate menu for changing frequency step. When the middle button is pressed, the signal generation starts. Middle button is pressed again for stopping the signal. More details can be found in the original site.
The Original Article : "DDS Function Generator"