INVERTING GATE WITH MAXIMIZED THERMAL NOISE IN RANDOM NUMBER GENERTION

摘要

A random number generator comprises a first high frequency (HF) oscillator, a second low frequency (LF) oscillator, and a sampling circuit. The HF oscillator generates a high frequency oscillating signal. The LF oscillator generates a low frequency oscillating signal. The LF oscillating signal is used to sample the HF oscillating signal to generate a sequence of random bits. In one preferred embodiment, the LF oscillator comprises a plurality of stages of inverters, and each inverter comprises a number of series-stacked minimum length transistors. The LF oscillating signal has a jitter distribution due to thermal noise present in each transistor of the LF oscillator. By series stacking a number of minimum length transistors in each inverter, the overall thermal noise in the LF oscillator is maximized to increase the jitter distribution of the LF oscillating signal and thereby increase the random behavior of the sequence of random bits.