Patent application number | Description | Published |
20090100122 | SATURATION AND ROUNDING IN MULTIPLY-ACCUMULATE BLOCKS - Saturation and rounding capabilities are implemented in MAC blocks to provide rounded and saturated outputs of multipliers and of add-subtract-accumulate circuits implemented using DSP. These features support any suitable format of value representation, including the x.15 format. Circuitry within the multipliers and the add-subtract-accumulate circuits implement the rounding and saturation features of the present invention. | 04-16-2009 |
20100228807 | Digital signal processing circuitry with redundancy and bidirectional data paths - Digital signal processing (“DSP”) circuit blocks are provided that can more easily work together to perform larger (e.g., more complex and/or more arithmetically precise) DSP operations if desired. These DSP blocks may also include redundancy circuitry that facilitates stitching together multiple such blocks despite an inability to use some block (e.g., because of a circuit defect). | 09-09-2010 |
20110161389 | LARGE MULTIPLIER FOR PROGRAMMABLE LOGIC DEVICE - A plurality of specialized processing blocks in a programmable logic device, including multipliers and circuitry for adding results of those multipliers, can be configured as a larger multiplier by adding to the specialized processing blocks selectable circuitry for shifting multiplier results before adding. In one embodiment, this allows all but the final addition to take place in specialized processing blocks, with the final addition occurring in programmable logic. In another embodiment, additional compression and adding circuitry allows even the final addition to occur in the specialized processing blocks. | 06-30-2011 |
20110219052 | DISCRETE FOURIER TRANSFORM IN AN INTEGRATED CIRCUIT DEVICE - Circuitry performing Discrete Fourier Transforms. The circuitry can be provided in a fixed logic device, or can be configured into a programmable integrated circuit device such as a programmable logic device. The circuitry includes a floating-point addition stage for adding mantissas of input values of the Discrete Fourier Transform operation, and a fixed-point stage for multiplying outputs of the floating-point addition stage by twiddle factors. The fixed-point stage includes memory for storing a plurality of sets of twiddle factors, each of those sets including copies of a respective twiddle factor shifted by different amounts, and circuitry for determining a difference between exponents of the outputs of the floating-point stage, and for using that difference as an index to select from among those copies of that respective twiddle factor in each of the sets. | 09-08-2011 |
20110238720 | SOLVING LINEAR MATRICES IN AN INTEGRATED CIRCUIT DEVICE - Circuitry for solving linear matrix equations involving a resultant matrix, an unknown matrix and a product matrix that is a product of the resultant matrix and the unknown matrix includes matrix decomposition circuitry for triangulating an input matrix to create a resultant matrix having a plurality of resultant matrix elements on a diagonal, and having a further plurality of resultant matrix elements arranged in columns below the resultant matrix elements on the diagonal. The matrix decomposition circuitry includes an inverse square root multiplication path that computes diagonal elements of the resultant matrix having an inverse square root module, and the said inverse square root module computes inverses of the diagonal elements to be used in multiplication in place of division by a diagonal element. Latency is hidden by operating on each nth row of a plurality of matrices prior to any (n+1)th row. | 09-29-2011 |
20110320513 | CALCULATION OF TRIGONOMETRIC FUNCTIONS IN AN INTEGRATED CIRCUIT DEVICE - Circuitry for computing a trigonometric function of an input includes circuitry for relating the input to another value to generate an intermediate value, circuitry for selecting one of the input and the intermediate value as a trigonometric input value, circuitry for determining respective initial values of a plurality of trigonometric functions for the trigonometric input value, and circuitry for deriving, based at least in part on a trigonometric identity, a final value of the first trigonometric function from the respective initial values of the plurality of trigonometric functions. The trigonometric function may be any of sine, cosine and tangent and their inverse functions. The trigonometric identities used allow a computation of a trigonometric function to be broken into pieces that either are easier to perform or can be performed more accurately. | 12-29-2011 |
20120233230 | DOUBLE-CLOCKED SPECIALIZED PROCESSING BLOCK IN AN INTEGRATED CIRCUIT DEVICE - Circuitry for increasing the precision of multipliers by a desired factor while limiting the increase in arithmetic complexity of the multiplier to that factor can be provided in a fixed logic device, or can be configured into a programmable integrated circuit device such as a programmable logic device (PLD). The smaller increase in arithmetic complexity, so that the increase is proportional to the increase in precision, rather than to the square of the increase in precision, is achieved by using specialized processing block components differently on alternating clock cycles. For example, to implement double precision, the same multiplier components are used in each of two clock cycles, but some specialized processing block internal structures (e.g., shifters and adders) are used differently in the two cycles, so that over the two cycles, a larger multiplication may be calculated from smaller partial products. | 09-13-2012 |
20120290819 | DSP BLOCK WITH EMBEDDED FLOATING POINT STRUCTURES - A specialized processing block includes a first floating-point arithmetic operator stage, a second floating-point arithmetic operator stage, and configurable interconnect within the specialized processing block for routing signals into and out of each of the first and second floating-point arithmetic operator stages. In some embodiments, the configurable interconnect may be configurable to route a plurality of block inputs to inputs of the first floating-point arithmetic operator stage, at least one of the block inputs to an input of the second floating-point arithmetic operator stage, output of the first floating-point arithmetic operator stage to an input of the second floating-point arithmetic operator stage, at least one of the block inputs to a direct-connect output to another such block, output of the first floating-point arithmetic operator stage to the direct-connect output, and a direct-connect input from another such block to an input of the second floating-point arithmetic operator stage. | 11-15-2012 |
20130332497 | MODULAR DIGITAL SIGNAL PROCESSING CIRCUITRY WITH OPTIONALLY USABLE, DEDICATED CONNECTIONS BETWEEN MODULES OF THE CIRCUITRY - Digital signal processing (“DSP”) circuit blocks are provided that can more easily work together to perform larger (e.g., more complex and/or more arithmetically precise) DSP operations if desired. These DSP blocks may also include redundancy circuitry that facilitates stitching together multiple such blocks despite an inability to use some block (e.g., because of a circuit defect). Systolic registers may be included at various points in the DSP blocks to facilitate use of the blocks to implement systolic form, finite-impulse-response (“FIR”), digital filters. | 12-12-2013 |
20140082035 | MODULAR DIGITAL SIGNAL PROCESSING CIRCUITRY WITH OPTIONALLY USABLE, DEDICATED CONNECTIONS BETWEEN MODULES OF THE CIRCUITRY - Digital signal processing (“DSP”) circuit blocks are provided that can more easily work together to perform larger (e.g., more complex and/or more arithmetically precise) DSP operations if desired. These DSP blocks may also include redundancy circuitry that facilitates stitching together multiple such blocks despite an inability to use some block (e.g., because of a circuit defect). Systolic registers may be included at various points in the DSP blocks to facilitate use of the blocks to implement systolic form, finite-impulse-response (“FIR”), digital filters. | 03-20-2014 |
20140289293 | LARGE MULTIPLIER FOR PROGRAMMABLE LOGIC DEVICE - A plurality of specialized processing blocks in a programmable logic device, including multipliers and circuitry for adding results of those multipliers, can be configured as a larger multiplier by adding to the specialized processing blocks selectable circuitry for shifting multiplier results before adding. In one embodiment, this allows all but the final addition to take place in specialized processing blocks, with the final addition occurring in programmable logic. In another embodiment, additional compression and adding circuitry allows even the final addition to occur in the specialized processing blocks. | 09-25-2014 |