Intel has developed a new circuit for generating random numbers that has a fully digital design, making it possible to incorporate it into the microprocessor die for maximum encryption security.

At the heart of the new design is a cross-coupled inverter, a combination of two basic circuit components that is essentially a memory capable of storing a single 1 or 0. This memory, though, is designed to be unreliable; it can be tipped between its two possible outputs by the influence of thermal noise from the surrounding silicon. Since that thermal noise is random, the circuit’s output should be, too.