Binary adder having a fixed operand and parallel-serial binary multiplier incorporating such an adder

Binary adder having a fixed operand and a parallel-serial binary multiplier incorporating such an adder. The multiplier comprises a dedicated adder, whose elements (transistors, logic gates, etc.) are wired to incorporate the value of the fixed operand B. The non-fixed operand D is applied in serial form to the control input of a multiplexer. The multiplier also comprises an accumulator-shift register for storing a partial result A of the multiplication. As a function of the state of the multiplexer, the register receives A or A+B.