analog voltage is variable, digital is discrete patterns.
but what is considered HIGH and what is considered LOW is determined by the logic-level voltage.
voltage source is different from logic-level voltage. usually, we’ll need to use a regulator if powering from an analog source.
all 7400 ic-s can be connected together.
added to electrical components.
a logic-level shifter can shift a 3.3 (or simos protocol) to a 5v protocol.
there is a comparator inside that compares incoming voltage to the threshold.
