I'm using the AD9914 eval board to generate short, phase stable 500 MHz bandwidth frequency ramps at a 10-100 Hz repetition rate. The board is working great for this application, except the phase of the ramps slowly walks off over a period of 3-5 minutes. However, when I calibrate the DAC by pushing a button in the eval board software it resets the phase of the board, halting the slow phase walkoff. If I push this button every ~30 seconds I can effectively solve the problem. This is an OK fix, but I would like to be able to automate the DAC calibration or fix this problem in another automated fashion. I was wondering if anyone has any recommendations for setting up an automatic DAC calibration every few seconds, or another approach to this issue?