An RNG circuit is connected to the parallel port of a computer. The circuit includes a flat source of white noise and a CMOS amplifier circuit compensated in the high frequency range. A low-frequency cut-off is selected to maintain high band-width yet eliminate the 1/f amplifier noise tail. A CMOS comparator...http://www.google.co.uk/patents/US6763364?utm_source=gb-gplus-sharePatent US6763364 - Random number generator and generation method
