Altera Corporation

Philip Pan

Chiakang Sung

Joseph Huang

Yan Chong

Bonnie I Wang

Khai Nguyen

Xiaobao Wang

In Whan Kim

Tzung-Chin Chang

Andy Louie Lee

Gopinath Rangan

Brian D Johnson

Gopi Rangan

Lu Zhou

Aniket Kadkol

Jonathan Chung

David Lewis

Thomas Henry White

Johnson Tan

Surgey Y Shumarayev

Vaughn Betz

Paul Leventis

Thomas Yau-Tsun Wong

Bonnie L Wang

James G Schleicher, Ii

Ling Yu

Yen-Fu Lin

Xiabao Wang

Prosenjit Mal

Boonie I Wang

An integrated circuit having a logic element that includes an array of storage elements convertibly functioning as either a configuration random access memory (CRAM) or a static random access memory (SRAM) is provided. The logic element includes first and second pairs of data paths having dedicated multiplexers. In one embodiment, the first and second pairs of data paths are multiplexed into bit lines of a row of the array. The logic element also includes a data path control block generating control signals for each of the dedicated multiplexers. The control signals determine whether the storage elements function as a CRAM or a SRAM. A method for selectively configuring a memory array between a CRAM mode and SRAM mode are provided.

Scaleable look-up table based memory

Methods and apparatus for providing either high-speed, or lower-speed, flexible inputs and outputs. An input and output structure having a high-speed input, a high-speed output, a low or moderate speed input, and an low or moderate speed output is provided. One of the input and output circuits are selected and the others are deselected. The high-speed input and output circuits are comparatively simple, in one example having only a clear signal for a control line input, and are able to interface to lower speed circuitry inside the core of an integrated circuit. The low or moderate speed input and output circuits are more flexible, for example, having preset, enable, and clear as control line inputs, and are able to support JTAG boundary testing. These parallel high and lower speed circuits are user selectable such that the input output structure is optimized between speed and functionality depending on the requirements of the application.

Programmable high-speed I/O interface

Method and circuitry for implementing high speed multiple-data-rate interface architectures for programmable logic devices. The invention partitions I/O pins and their corresponding registers into independent multiple-data rate I/O modules each having at least one pin dedicated to the strobe signal DQS and others to DQ data signals. The modular architecture facilitates pin migration from one generation of PLDs to the next larger generation.

Multiple data rate interface architecture

A method and circuit with minimized clock skews in an IC. One embodiment includes placing an application specific IP block at a predetermined location in an integrated circuit (IC), the IC having a clock network that distributes a clock signal, the clock network having one or more clock buses, each clock bus providing the clock signal to a row of logic blocks of the IC, each clock bus having one or more clock nets; determining the electrical load on a first clock driver driving a first clock net of a first clock bus providing the clock signal to a first row of logic blocks; identifying at least one other target clock driver to be coupled to the first clock net, the at least one other target clock driver driving a clock net of a clock bus providing the clock signal to a row of logic blocks other than the first row of logic blocks; selecting the at least one other target clock driver to couple to the first clock net; coupling the at least one other target clock driver to the first clock net; and verifying by one or more types of simulation the desired functional and timing performance of the affected logic blocks after connection of the compatible clock nets.

Method and apparatus to minimize clock tree skew in ICs

A programmable memory interface circuit includes a programmable DLL delay chain, a phase offset control circuit and a programmable DQS delay chain. The DLL delay chain uses a set of serially connected delay cells, a programmable switch, a phase detector and a digital counter to generate a coarse phase shift control setting. The coarse phase shift control setting is then used to pre-compute a static residual phase shift control setting or generate a dynamic residual phase shift control setting, one of which is chosen by the phase offset control circuit to be added to or subtracted from the coarse phase shift control setting to generate a fine phase shift control setting. The coarse and fine phase shift control settings work in concert to generate a phase-delayed DQS signal that is center-aligned to its associated DQ signals.

High performance memory interface circuit architecture

Programmable high-speed interface

High-performance memory interface circuit architecture

Growing community of inventors

Fremont, CA, United States of America

Philip Pan