Current-mode CMOS cosine transform chip

An 8-point cosine transform chip has been designed and fabricated in a standard 3 mu m CMOS process. The architecture of the chip is based on the discrete cosine transform algorithm, where the product of the coefficient matrix and the input vector is realised in current mode operations. The coefficient values are determined by the ratios of transistor width and length with an accuracy corresponding to 6-7 bits. The settling time of the chip is 500 ns with a power dissipation of only 2 mW.