Hot switch between 5v and 3.3v buses for Signal Generator by uController For project description and firmware refer to github: https://github.com/ShaggyDog18/SignalGeneratorSD AD98333 module generates meandre (square signal) at its VCC level. So, if VCC bus is +5V, then amplitude of the square sugnal is 5V. In some cases a signal of 3.3v may be required. There are several solution: 1. use 3.3v power bus for entire solutoin. 2. add 3.3v voltage regulator and switch between 5v and 3.3v power bus for entire setup (plain rough solution). 3. add 3.3v voltage regulator and switch power bus of an output buffer (deployed). So, I deployed option 3: added an output cascade/buffer for meander signal only based on Schmitt-trigger (74LVC1G14) which is connected right to the AD9833 out pin, and flip its power bus between 5v and 3.3v from firmware (menu).