Computer drive for addition circuits of cryptographic processors, uses switching stage to switch computational potential through to output

摘要

A computer drive for adder circuits has a dual-rail input stage (10) for receiving at least one input operand and for outputting the input operand in non-inverting form. A switching stage (12) is designed to switch though a computation potential to an output (18) of the switching stage. A dual-rail output stage (14 a,b,c) has one input connected to the output (18 a,b,c) of the switching stage (12 a,b,c) and has a first output (26b) and a second output (26a) with output bit applied to the first output (26b) in a data mode. A node potential circuit is provided for coupling the internal node in the preparatory mode with the reference potential (Vss) and for decoupling the internal node in the data mode from the reference potential (Vss).