A true random number generator with high bit rate and low energy efficiency

In this paper, a novel feedback architecture of true random number generator based on tetrahedral ring oscillator is proposed. The random raw bits are fed back to produce control voltages, which control the transmission gates in ring oscillators. Since random fluctuations of the control voltages increase the phase jitter of the oscillator, this architecture improves the bit rate and randomness of random sequence. Besides, a post-processor is designed to enhance the randomness further. The circuit is implemented in TSMC 40-nm complementary metal oxide semiconductor (CMOS) process, and it takes up an area of 85 x 51 mu m. Measurement results show that the random number sequences pass the statistical randomness tests, with a low power consumption of 67 mu W, high speed of 45 Mbps, and low energy efficiency of 1.48 pJ/bit.

Automated summary

In this paper, a novel feedback architecture based on tetrahedral ring oscillator is proposed to improve the bit rate and randomness of random sequence. The random raw bits are fed back to produce control voltages, increasing the phase jitter of the oscillator. A post-processor is designed to enhance the randomness further. The circuit is implemented in TSMC 40-nm CMOS process, with low power consumption, high speed, and low energy efficiency.