With 3 outputs averaged with equal resistors, the possible output voltages can be Vss, 0.33*Vdd, 0.67*Vdd and Vdd. The two voltages in the middle are outside the 30%/70% spec for input voltages but not a lot so with typical parameters Vss and 0.33*Vdd will be a "0" and 0.67*Vdd and Vdd will be a "1" as is the case in the scope picture above. The division is 8 in this case so it would be possible to just connect Q4b back to the input to avoid the problem but the waveform will be different so it may affect the harmonics.However, it's not going to behave predictably wired as shown. Resistively mixing the outputs and feeding that to an input will result in non-valid levels at the Data input, unpredictable behavior, and possibly significant heat. If you place an SP5T switch between the Q\ outputs and the Data input, you can select your divider ratio.
With a 5V supply and typical transistor threshold voltages of 1.5V, there will be some cross current in the data input buffer most of the time but probably relatively minor. It will be much worse if powered by 12V or 15V.
Statistics: Posted by Synthiq — Thu Oct 03, 2024 11:23 pm