Patent ID: 7683725

Claim:
A ring oscillator structure for generating multiple phases using multiple unit oscillators, the structure comprising: a three-dimensional oscillator structure comprised of multiple two-dimensional oscillator structures, each two-dimensional oscillator structure comprised of: two or more unit oscillators, each unit oscillator implemented by a ring oscillator having M stages, where M is greater than or equal to two; and a loop coupling the two or more unit oscillators to generate multiple phases, the number of phases equal to the product of the number of unit oscillators and M, wherein the coupling aligns inputs and outputs of the unit oscillators sequentially between a first unit oscillator and a last unit oscillator and shifts the outputs of last unit oscillator by one position to loop back to the first unit oscillator; and wherein the three-dimensional oscillator structure aligns inputs and outputs of the unit oscillators sequentially between the first unit oscillator of a first two-dimensional oscillator structure and the last unit oscillator of a last two-dimensional oscillator structure and shifts the outputs of the last unit oscillator of the last two-dimensional oscillator structure by one position to loop back to the first unit oscillator of the first two-dimensional oscillator structure.