so i need an 8bit DAC . the R2R resistor ladder is good . it gives 256 different voltage levels .
i need something like that but . now i have 8 pins for the DAC and a sync pin .
the sync pin is always HIGH while the DAC is being used .
so it’s a sync pin and 8 pins . the total would be 9 pins but one of them is always on .
so if the sync pin is on HIGH and all the rest are LOW . the voltage output must be 0.3v or something around it .
if the sync pin is HIGH and all the 8 pins are also high , the voltage output must be 1.0v or something around it .
i need 256 voltage levels . the thing is , how can i calculate the resistor values ?