herpderp shares his waveform generator in the project log forum:
Here is my last project, a tiny waveform generator based on my previous project and some components:
– An AD9834 (DDS chip with sinus/triangle output)
– 2 x AD5310 (10bit DAC: one for the Vpp control, another one the offset control)
– 3 x LM7171 (Fast OPA)
– 3 x LT1616 (switching regulator: +5V, +7V, -7V)
This waveform generator is directly powered by a standard 12V jack and is capable of outputting a 10Vpp signal at 1MHz (between -5V and +5V, sinus waveform, no load). Above 1MHz, the output starts fading, reaching only 9Vpp at 4MHz (maximal frequency). Frequency, amplitude and offset are digitally controlled through the smart TFT.
Three “basic” waveforms are provided: sinus and triangle, coming from the DDS chip (0.1Hz to 4MHz, 0.1Hz step), and PWM coming from the microcontroller (0.1Hz to 1MHz, variable steps).
Check out the video after the break.