To achieve high performance scalar multiplication arithmetic in Elliptic Curve Cryptography (ECC) based on GF(2m), a high-speed constant-time division module with optimized architecture is proposed in this paper. Modified from the traditional extended Euclidean Great Common Divisor (GCD) division algorithm, the presented algorithm computes a single multiplicative inverse or division in constant m iterations, i.e. m clock cycles, in GF(2m), which obtains a tremendous reduction (specifically more than 50%) on computing time compared with previous works. Combined with the meticulously optimized architecture, this novel division module achieves lower area-time complexity, which makes it an excellent option for high performance ECC design.

In this paper, a novel device/circuit co-design scheme, namely Dynamic-Adjusting Threshold-Voltage Scheme (DATS) for independent-gate mode FinFET circuits has been proposed. The main idea of this scheme is that a pair of back-gate bias of FinFETs is adjusted dynamically to change threshold voltage according to the system operating frequency and operating mode, which could optimize circuit power, especially leakage power. The experimental and simulation result shows that the leakage power dissipation reduced greatly when circuits operate at the lower frequency, and the energy-delay product of FinFET circuits is reduced by 30% approximately.