@Mitch Bailey hello could you please clarify that R2R 3 bit DAC OUTPUT to make upto 5v I have to give 3 input bits voltage ref in analog ?

@Rafeeq Khan Mohammed Sorry, but I’m not even close to an analog circuit expert. I have no idea what you are asking. Is R2R rail to rail? Isn’t DAC output an analog signal? Do you mean ADC? Are ADC and DAC the same thing? I don’t understand how you’d have 3 bits of an analog signal. I understand having 3 digital bits to represent 8 levels of an analog signal. Is that what you mean? To me it seems that you want to create a DAC that converts a 3 bit digital signal into an analog signal with the following levels. 0V, 0.7V, 1.4V, 2.1V, 2.9V, 3.6V, 4.3V, 5V. You then want to convert an input pulse (maximum 1.8V or 3.3V or 5V), to a pulse of the same frequency but with an amplitude given by the output of the dac. Is that correct? The 6 transistor level shifter that you propose may be sufficient for both low and high voltages.

@Mitch Bailey thank you so much