Therefore {HEAD ~ this circuit} produces a digital ramp signal with a slope and frequency proportional to the numerical value of {TAIL ~ the input digital word} 
Therefore { HEAD ~ this circuit } produces a digital ramp signal with a slope and frequency proportional to the numerical value of { TAIL ~ the input digital word }
OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL