A weblog focused on interesting circuits, ideas, schematics and other information about microelectronics and microcontrollers.
True Random Number Generator
True random number generator, generated by AVR-based hardware (not a computed pseudorandom numbers).
The numbers are generated by sampling a source of random noise. The noise comes from a PN junction biased into breakdown. The noise is amplified and turned into a random bit by a comparator. Bits are gathered up and sent out to a PC where they are buffered, ready for use. The AVR regulates the PN junction boost voltage to about 12V by adjusting the PWM duty cycle. The AVR also contains the comparator which produces the binary digits from the noise. A simple display is included in the circuit, which currently displays the mean average of all the numbers generated so far.