Active Test and Alteration of Sample Times For a Ring Based Random Number Generator

An apparatus includes: a plurality of bit producing circuits; a controller setting a sample frequency at which bits from the bit producing circuits are sampled; and a plurality of test circuits determining if bits sampled from each of the bit producing circuits are random, wherein the controller adjusts the sample frequency if the test circuits determine that the sampled bits are not random. A method performed by the apparatus is also included.