Linear voltage-amplitude to pulse-width conversion utilizing a controlled unijunction monostable multivibrator

A circuit that achieves linear wide-range voltage-amplitude to pulse-width conversion is presented. The circuit combines a unijunction transistor operating in an inverted mode, a field- effect transistor, and an integrated circuit flip-flop to obtain highly linear conversion. Other advantages are low-ments, excellent interface characteristics, asynchronous operation, simplicity, and a wide range of pulse-width variation. The circuit operation is discussed, and major design equations are derived. In the experimental circuit that is included, linearity of conversion is within 0.5 percent of full scale pulse width. The pulse width is controllable over the range of 85 to 6 ms for a control voltage variation of 0 to 1.6 volts.