Jean Nicolai

Method for the fast charging of a battery and integrated circuit for the implementation of this method

To carry out a fast charging of a battery, a high current is injected into this battery while, at the same time, the terminals of this battery are monitored. This injection is stopped when this voltage undergoes an inflection of its variation. It is shown that, given the security of the system, it is possible to charge nickel-cadmium or nickel-metal-hydride type batteries with currents that are even higher than in prior systems.

A Physical Approach for Stochastic Modeling of TERO-Based TRNG

Security in random number generation for cryptography is closely related to the entropy rate at the generator output. This rate has to be evaluated using an appropriate stochastic model. The stochastic model proposed in this paper is dedicated to the transition effect ring oscillator (TERO) based true random number generator (TRNG) proposed by Varchola and Drutarovsky in 2010. The advantage and originality of this model is that it is derived from a physical model based on a detailed study and on the precise electrical description of the noisy physical phenomena that contribute to the generation of random numbers. We compare the proposed electrical description with data generated in a 28 nm CMOS ASIC implementation. Our experimental results are in very good agreement with those obtained with both the physical model of TERO’s noisy behavior and with the stochastic model of the TERO TRNG, which we also confirmed using the AIS 31 test suites.