Patent application number | Description | Published |
20090013227 | Method Using Non-Linear Compression to Generate a Set of Test Vectors for Use in Scan Testing an Integrated Circuit - A method is provided that uses non-linear data compression in order to generate a set of test vectors for use in scan testing an integrated circuit. The method includes the steps of initially designing the set of test vectors, and selecting one of multiple available coding schemes for each test vector. The method further comprises operating a random pattern generator to generate data blocks, each corresponding to one of the test vectors, wherein the data block corresponding to a given test vector is encoded with a bit pattern representing the coding scheme of the given test vector. The corresponding data block also has a bit length that is less than the bit length of the given test vector. Each data block is routed to at least one of a plurality of decoders, wherein each decoder is adapted to recognize the coding scheme represented by one of the bit patterns. A decoder is operated to generate one of the test vectors, when the decoder receives the block corresponding to the generated test vector, and recognizes the coding scheme that is encoded by the received data block. | 01-08-2009 |
20090048794 | Method for Detecting Noise Events in Systems with Time Variable Operating Points - A circuit for detecting noise events in a system with time variable operating points is provided. A first voltage, which is averaged over time, is compared to a second voltage. A signal is generated to instruct circuits within a processor to initiate actions to keep a voltage from drooping further. | 02-19-2009 |
20090094307 | ACCURACY IMPROVEMENT IN CORDIC THROUGH PRECOMPUTATION OF THE ERROR BIAS - Performing a calculation using a coordinate rotation digital computer (CORDIC) algorithm. Execution of the CORDIC algorithm is begun. An error introduced by a truncated vector as a result of executing the CORDIC algorithm is pre-computed. The error is incorporated into a subsequent iteration of the CORDIC algorithm. Execution of the CORDIC algorithm is completed. The result of the CORDIC algorithm is stored. | 04-09-2009 |
20090113107 | DIFFERENTIAL TRANSMITTER CIRCUIT - A driver circuit is configured as a frequency compensated differential amplifier having one input coupled to a first data signal and a second input coupled to a second data signal. Each stage of the differential amplifier is biased with a current source. The driver circuit generates a first output signal coupled to the input of a first transmission line and a second output signal coupled to the input of a second transmission line. The first and second output signals are generated as the difference between the first and second data signals amplified by a compensated gain. A compensation network that attenuates the low frequency components of the input signals relative to the high frequency components is coupled between current sources biasing the differential amplifier. The outputs of the first and second transmission lines are coupled to the inputs of a differential receiver that may or may not be frequency compensated. | 04-30-2009 |
20100027361 | Information Handling System with SRAM Precharge Power Conservation - An information handling system (IHS) includes a processor with on-chip or off-chip SRAM array. After a read operation, a control circuit may instruct the SRAM array to conduct a precharge operation, or alternatively, instruct the SRAM array to conduct an equalize bitline voltage operation. A read operation may follow the precharge operation or the equalize bitline voltage operation. The control circuit may instruct the SRAM array to conduct an equalize bitline voltage operation if an equalized voltage of a bitline pair exhibits more that a predetermined amount of voltage. Otherwise, the control circuit instructs the SRAM array to conduct a precharge operation before the next read operation. | 02-04-2010 |
20100180168 | SCAN CHAIN FAIL DIAGNOSTICS - A method comprises generating a test pattern for a device under test (DUT), wherein the DUT comprises a plurality of scan chains coupled to a plurality of multiple input shift registers (MISRs). The plurality of faults detected by a first MISR and by a second MISR are identified. In the event the plurality of faults detected by the first MISR does not include any of the plurality of faults detected by the second MISR and the plurality of faults detected by the second MISR does not include any of the plurality of faults detected by the first MISR, the first MISR and the second MISR are coupled as an independent MISR pair. The test pattern is applied to the DUT to generate a scan chain output. The independent MISR pair captures the scan chain output to generate a test signature. The test signature is compared with a known good signature. | 07-15-2010 |
20110141826 | Cache Array Power Savings Through a Design Structure for Valid Bit Detection - A mechanism is provided for gating a read access of any row in a cache access memory that has been invalidated. An address decoder in the cache access memory sends a memory access to a non-gated wordline driver and a gated wordline driver associated with the memory access. The non-gated wordline driver outputs the data stored in a valid bit memory cell to the gated wordline driver in response to the non-gated wordline driver determining the memory access as a read access. The gated wordline driver determines whether the data from the valid bit memory cell from the non-gated wordline driver indicates either valid data or invalid data in response to the gated wordline driver determining the memory access as a read access and denies an output of the data in a row of memory cells associated with the gated wordline driver in response to the data being invalid. | 06-16-2011 |
20110258395 | Preventing Fast Read Before Write in Static Random Access Memory Arrays - A mechanism is provided for enabling a proper write through during a write-through operation. Responsive to determining the memory access as a write-through operation, first circuitry determines whether a data input signal is in a first state or a second state. Responsive to the data input signal being in the second state, the first circuitry outputs a global write line signal in the first state. Responsive to the global write line signal being in the first state, second circuitry outputs a column select signal in the second state. Responsive to the column select signal being in the second state, third circuitry keeps a downstream read path of the cache access memory at the first state such that data output by the cache memory array is in the first state. | 10-20-2011 |
20130141992 | VOLATILE MEMORY ACCESS VIA SHARED BITLINES - A memory includes an array of memory cells that form rows and columns. The rows of the array include memory cell pairs. The memory cells may include two cross-coupled inverters and two pass-devices that couple to alternate sides of the cross-coupled inverters. The two memory cells of a memory cell pair share a common intra-pair bitline. Adjacent memory cell pairs share a common inter-pair bitline. To perform a data read operation on a particular memory cell in a memory cell pair in the rows and columns of the array, wordline drive circuitry transmits wordline activate signals to select both the row for the data read operation and a particular one of the pair of memory cells for the data read operation. | 06-06-2013 |
20130141997 | SINGLE-ENDED VOLATILE MEMORY ACCESS - A memory includes an array of memory cells that form rows and columns. The rows include memory cell pairs. The memory cells may include two cross-coupled inverters and two pass-devices that couple to alternate sides of the cross-coupled inverters. For a read operation, a wordline drive circuit selects one memory cell of the pair, the selected memory cell being an addressed memory cell while the remaining cell is an unaddressed memory cell. In response to a wordline enable signal, a pass gate in the addressed memory cell couples the addressed memory cell via a complement bitline to an evaluation gate that resolves the data from the read operation. During the read operation, the unaddressed memory cell couples via another pass gate to a true bitline that terminates without an evaluation gate to conserve energy. | 06-06-2013 |
20140098590 | VOLATILE MEMORY ACCESS VIA SHARED BITLINES - A memory includes an array of memory cells that form rows and columns. The rows of the array include memory cell pairs. The memory cells may include two cross-coupled inverters and two pass-devices that couple to alternate sides of the cross-coupled inverters. The two memory cells of a memory cell pair share a common intra-pair bitline. Adjacent memory cell pairs share a common inter-pair bitline. To perform a data read operation on a particular memory cell in a memory cell pair in the rows and columns of the array, wordline drive circuitry transmits wordline activate signals to select both the row for the data read operation and a particular one of the pair of memory cells for the data read operation. | 04-10-2014 |
20140098597 | SINGLE-ENDED VOLATILE MEMORY ACCESS - A memory includes an array of memory cells that form rows and columns. The rows include memory cell pairs. The memory cells may include two cross-coupled inverters and two pass-devices that couple to alternate sides of the cross-coupled inverters. For a read operation, a wordline drive circuit selects one memory cell of the pair, the selected memory cell being an addressed memory cell while the remaining cell is an unaddressed memory cell. In response to a wordline enable signal, a pass gate in the addressed memory cell couples the addressed memory cell via a complement bitline to an evaluation gate that resolves the data from the read operation. During the read operation, the unaddressed memory cell couples via another pass gate to a true bitline that terminates without an evaluation gate to conserve energy. | 04-10-2014 |