共查询到20条相似文献,搜索用时 140 毫秒
1.
Bongjin Jung Burleson W.P. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》1998,6(3):475-483
We present a parallel algorithm, architecture, and implementation for efficient Lempel-Ziv (LZ)-based data compression. The parallel algorithm exhibits a scalable, parameterized, and regular structure and is well suited for VLSI array implementation. Based on our parallel algorithm and systematic design methodologies, two semisystolic array architectures have been developed which are low power and area efficient. The first architecture trades off the compression speed for the area and has a low run-time overhead for multichannel compression. The second architecture achieves a high compression rate (one data symbol per clock) at the expense of the area due to a large clock load and global wiring. Compared to a recent state-of-the-art parallel architecture, our first array structure requires significantly less chip area (≃330 k versus ≃36 k transistors) and more than an order of magnitude less power (≈1.0 W versus ≈70 mW) while still providing the compression speed required for most data communication applications. Hence, data compression can be adopted in portable data communication as well as wireless local area networks. The second architecture has at least three times less area and power while providing the same constant compression rate. To demonstrate the correctness of our design, a prototype module for the first architecture has been implemented using 1.2 μ complementary metal-oxide-semiconductor (CMOS) technology. The compression module contains 32 simple and identical processors, has an average compression rate of 12.5 million bytes/s, and consumes 18.34 mW without the dictionary (≈70 mW with a 4.1k SRAM for the dictionary) while operating at a 100 MHz clock rate (simulated) 相似文献
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Cangsang Zhao Bhattacharya U. Denham M. Kolonsek J. Lu Y. Yong-Gee Ng Nintunze N. Sarkez K. Varadarajan H.D. 《Solid-State Circuits, IEEE Journal of》1999,34(11):1564-1570
An 18-Mbit CMOS pipeline-burst cache SRAM achieves a 12.3-Gbyte/s data transfer rate with 1.54-Gbit/s/pin I/O's. The SRAM is fabricated on a 0.18-μm CMOS technology. The 14.3×14.6-mm2 SRAM chip uses a 5.59-μm2, six-transistor cell. Circuit techniques used for achieving high bandwidth include fully self-timed array architecture, segmented hierarchical sensing with separated global read/write bitlines in different metal layers, a high-speed data-capture technique, a reduced-swing output buffer, and a high-sensitivity, high-bandwidth input buffer 相似文献
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This work presents a low‐voltage static random access memory (SRAM) technique based on a dual‐boosted cell array. For each read/write cycle, the wordline and cell power node of selected SRAM cells are boosted into two different voltage levels. This technique enhances the read static noise margin to a sufficient level without an increase in cell size. It also improves the SRAM circuit speed due to an increase in the cell read‐out current. A 0.18 µm CMOS 256‐kbit SRAM macro is fabricated with the proposed technique, which demonstrates 0.8 V operation with 50 MHz while consuming 65 µW/MHz. It also demonstrates an 87% bit error rate reduction while operating with a 43% higher clock frequency compared with that of conventional SRAM. 相似文献
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The performance of the processor core depends on the configuration parameters and utilization of on-chip memory in multimedia applications such as image, video and audio processing. The design of the on-chip memory architecture is critical for power and area efficient design without compromising quality in data-intensive computing applications. This paper proposes a design of high speed, area, and energy efficient Static Segment On-Chip (SSOC) memory for error-tolerant applications. In this static segment method, n-bit data array is reduced by m-bit data array for significant value of input data to achieve balanced design metrics at the cost of accuracy. The proposed m-bit static segmentation algorithm is implemented and verified in Single Port Static Random Access Memory (SP SRAM) architecture for the approximate computing applications. From the overall simulation results, the proposed 4-bit SSOC SP SRAM design provides 49.02% area savings, 50.62% power reduction and 16.92% speed improvement at the cost of 0.64% Peak Signal to Noise Ratio (PSNR) and exhibits same visual quality in comparison with the existing 8-bit conventional on-chip SP SRAM design in the image processing applications. 相似文献
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Kuo C. Toms T. Neel B.T. Jelemensky J. Carter E.A. Smith P. 《Solid-State Circuits, IEEE Journal of》1990,25(1):61-67
A complete data retention test of a CMOS SRAM array accomplished at room temperature using the soft-defect detection (SDD) technique is reported. The SDD technique uses a connectivity analysis and cell-array current test to detect physical open faults that can cause data retention failures. An extensive circuit analysis was made to establish the operation theory and special circuit design features required for SDD. Complete SDD circuits have been developed and implemented into a 16 K CMOS SRAM module for a 32-b microcontroller. Full operation and effectiveness of the SDD technique were verified from a special experimental 16 K CMOS RAM module with built-in defective cells. the SDD technique can accomplish not only the retention test at room temperature, but also the detection of other defects that were heretofore impractical to detect using the conventional retention test technique of high-temperature bakes and functional tests 相似文献
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提出一种使用环形振荡器对SRAM型FPGA内部延迟进行精确测试的方法。该方法利用SRAM型FPGA的可重构性在其内部构造环形振荡器,通过基准信号对分频后的振荡信号周期进行测量,从而得到环振回路中逻辑部件的延迟值。应用该方法,对一款Virtex-4型FPGA的内部延迟进行测试。结果表明:在环振初始振荡频率小于芯片工作极限频率的情况下,延迟测试的误差小于1 ps,与其他检测FPGA内部延迟故障的方法相比,检测精度有很大的提高,同时,该方法对SRAM型FPGA具有较高的普遍适用性。 相似文献
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A CMOS static RAM (SRAM) circuit capable of detecting and storing optically transmitted data is described. Bits of data are transferred to the memory circuit via an array of parallel light beams. A 16-b optoelectronic SRAM was fabricated in a standard bulk CMOS process and tested using argon and helium-neon lasers. Data contained in an array of 16 light beams with an average power of 3.35 μW/pixel were successfully transferred to the SRAM in parallel fashion. The storage of the optical information was verified by electronically addressing each cell. The optical data transfer technology is extended to other systems in which high speed and parallelism are essential 相似文献
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Lijun Zhang Yue Yu Jianbin Zheng Xiaoyu Song 《International Journal of Electronics》2013,100(9):1281-1290
This article presents a novel built-in self-test (BIST) scheme at full speed test where access time test is performed. Based on normal BIST circuits, we harness an all digital phase locked loop to generate a high-frequency clock for static random access memory (SRAM) performance test at full speed. A delay chain is incorporated to achieve the four-phase clock. As inputs to SRAM, clock, address, data are generated in terms of the four-phase clock. Key performance parameters, such as access time, address setup and hold times, are measured. The test chip has been fabricated by United Microelectronics Corporation 55?nm CMOS logic standard process. According to test results, the maximum test frequency is about 1.3?GHz, and the test precision is about 35?ps at the typical process corner with supply voltage 1.0?V and temperature 25°C. 相似文献
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Cserveny S. Sumanen L. Masgonty J.-M. Piguet C. 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2005,52(10):636-640
A low-power embedded SRAM for a large range of applications has been implemented in a standard digital 0.18-/spl mu/m process. The leakage current in the cells is reduced by using a source-body bias not exceeding the value that guaranties safe data retention, and less leaking nonminimum length transistors. Locally short-circuiting this bias, speed and noise margin loss in active mode is avoided, especially for low supply voltages. The bias is generated internally at the carefully designed equilibrium between cell, switch, and diode limiter leakages averaged over the array. The leakage of the full SRAM, including an optimized periphery, is reduced more than 20 times. Used in an industrial RF transceiver, the measurements confirm its performances. 相似文献
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Yates R.B. Thacker N.A. Evans S.J. Walker S.N. Ivey P.A. 《Solid-State Circuits, IEEE Journal of》1995,30(3):244-250
A new VLSI processor (DIP chip) for image compression is presented which combines principles of multipipeline and array processing. The device is not specific to any one image compression algorithm and can be regarded as a general purpose processor. The chip has been implemented using a CMOS 1.0-μm process on a 14.4×13.5-mm2 die. An internal clock frequency of 40 MHz results in 1.2×109 operations/s on 8-bit data. Solutions to problems associated with the large bandwidth required, for both image data and instruction streams, is the main aim of the paper. The necessary problem of increasing the array clock frequency relative to the input/output clock frequency without the need for a large on-chip instruction cache or fast external clock speeds is also addressed 相似文献
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With the migration toward low supply voltages in low-power SRAM designs, threshold and supply voltage fluctuations will begin to have larger impacts on the speed and power specifications of SRAM's. We present techniques based on replica circuits which minimize the effect of operating conditions' variability on the speed and power. Replica memory cells and bitlines are used to create a reference signal whose delay tracks that of the bitlines. This signal is used to generate the sense clock with minimal slack time and control wordline pulsewidths to limit bitline swings. We implemented the circuits for two variants of the technique, one using bitline capacitance ratioing in a 1.2-μm 8-kbyte SRAM, and the other using cell current ratioing in a 0.35-μm 2-kbyte SRAM. Both the RAM's were measured to operate over a wide range of supply voltages, with the latter dissipating 3.6 mW at 150 MHz at 1 V and 5.2 μW at 980 kHz at 0.4 V 相似文献
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《Circuits and Systems II: Express Briefs, IEEE Transactions on》2008,55(9):912-916
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In order to guarantee the proper operation of a recessed channel array transistor (RCAT) pseudo SRAM, the back‐bias voltage must be changed in response to changes in temperature. Due to cell drivability and leakage current, the obtainable back‐bias range also changes with temperature. This paper presents a pseudo SRAM for mobile applications with an adaptive back‐bias voltage generator with a negative temperature dependency (NTD) using an NTD VBB detector. The proposed scheme is implemented using the Samsung 100 nm RCAT pseudo SRAM process technology. Experimental results show that the proposed VBB generator has a negative temperature dependency of ?0.85 mV/°C, and its static current consumption is found to be only 0.83 µA@2.0 V. 相似文献
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Saito Y. Shimazu Y. Shimizu T. Shirai K. Fujioka I. Nishiwaki Y. Hinata J. Shimotsuma Y. Sakao M. 《Solid-State Circuits, IEEE Journal of》1993,28(11):1071-1077
A 1.71-million transistor CISC CPU chip for the business computer has been developed. The chip is implemented in a 0.8-μm CMOS double-polysilicon double-metal technology. The 16.3-mm×12.7-mm device contains a 16-kilobyte cache and 192 entries TLB and operates at 40 MHz. The sustained high performance in a complexed instruction set has been realized by a large horizontal microprogram that controls two 32-b ALU's. The cache and TLB employ a 77-μm2 SRAM using load resistors formed by the second polysilicon; these are accessed in one-half clock cycle and are tested at an 8 bytes per clock rate utilizing a new test strategy 相似文献
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DS3070W是Dallas公司最新推出的单片、内含实时时钟的非易失性静态存储器.该器件内部集成了16 Mb NV SRAM、非易失性控制器、实时时钟和一个锂锰(ML)可充电电池.介绍了DS3070W的性能特点及工作原理,给出了它与AT89C51的典型应用电路及子程序. 相似文献
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The design of nanoscale static random access memory (SRAM) circuits becomes increasingly challenging due to the degraded data stability, weaker write ability, increased leakage power consumption, and exacerbated process parameter variations in each new CMOS technology generation. A new asymmetrically ground-gated seven-transistor (7T) SRAM circuit is proposed for providing a low leakage high data stability SLEEP mode in this paper. With the proposed asymmetrical 7T SRAM cell, the data stability is enhanced by up to 7.03x and 2.32x during read operations and idle status, respectively, as compared to the conventional six-transistor (6T) SRAM cells in a 65 nm CMOS technology. A specialized write assist circuitry is proposed to facilitate the data transfer into the new 7T SRAM cells. The overall electrical quality of a 128-bit×64-bit memory array is enhanced by up to 74.44x and 13.72% with the proposed asymmetrical 7T SRAM cells as compared to conventional 6T and 8T SRAM cells, respectively. Furthermore, the new 7T SRAM cell displays higher data stability as compared to the conventional 6T SRAM cells and wider write voltage margin as compared to the conventional 8T SRAM cells under the influence of both die-to-die and within-die process parameter fluctuations. 相似文献