Altera Corporation

Chee Cheong Tan

Kyung Suk Oh

Loke Yip Foo

Wai Ling Lee

Yee Huan Yew

Mei See Chin

Chooi Ian Loh

Hui Lee Teng

The present disclosure relates to an innovative method of assigning signals to general-purpose input/output pads of an integrated circuit chip. An inductance matrix for the input/output pads is obtained. A candidate assignment is made of a differential signal to a pair of the input/output pads, and a differential mutual inductance is determined for each open pad location in relation to the pair of input/output pads. Single-ended signals are assigned to open pad locations having the lowest differential mutual inductances. The jitter contribution due to each assigned single-ended signal is computed, and a total jitter is updated. In a first embodiment, said assigning, computing and updating steps are repeated until the total jitter exceeds a total jitter budget. In a second embodiment, said assigning, computing and updating steps are repeated until a number of assigned single-ended signals is equal to a target number. Other embodiments and features are also disclosed.

Method to optimize general-purpose input/output interface pad assignments for integrated circuit

Growing community of inventors

Georgetown, Malaysia

Chee Cheong Tan