对基于模代数的三值触发器的研究

本文用模代数讨论三值触发器。提出了基于模代数的三值 JK 触发器。与基于 Post代数的三值 JK 触发器相比,它的逻辑功能是均衡的,它能像二值 JK 触发器一样方便地构成另外二种常用的触发器:三值 D 型触发器与三值 T 型触发器。此外,由时序电路的设计实例,也证实了因它的功能较强而能导致较简单的激励函数与组合电路。     

双端置数技术与高值CMOS触发器设计

在分析以往高值触发器困难的基础上本文提出了双端予置的逻辑设计方案。应用传输函数理论对四值ＣＭＯＳ触发器进行了电路设计。结果表明，与存贮相同信息量的二个二值触发器相比，它有较简单的结构与较快的工作速度。     

电流型CMOS脉冲D触发器设计

该文根据脉冲触发器的设计要求,结合阈算术代数系统,提出一种电流型CMOS脉冲D触发器的通用结构,用于二值及多值电流型CMOS脉冲触发器的设计,并可方便地应用于单边沿和双边沿触发。在此结构的基础上设计了电流型CMOS二值、三值以及四值脉冲D触发器。采用TSMC 180 nm CMOS工艺参数对所设计的电路进行HSPICE模拟后表明所设计的电路具有正确的逻辑功能和良好的瞬态特性,且较以往文献提出的电流型D触发器,优化了触发器的建立时间和保持时间,二值和四值触发器最差最小D-Q延时比相关文献的主从触发器降低了59.67%和54.99%,比相关文献的边沿触发器降低了4.62%以上,所用晶体管数也相对减少,具有更简单的结构以及更高的电路性能。     

基于集成门电路的三值单稳态触发器研究

通过对二值单稳态触发器设计原理的重新归纳,本文从三值三稳态触发器的正确设计出发,提出了二种三值单稳态触发器的设计方案。以ＲＣ微分电路为定时电路的设计已用ＰＳＰＩＣＥ程序进行计算机验证。     

多值时钟与并列式多拍多值触发器

通过对现有多值主从触发器－串列式二拍多值主从触发器的分析，本文指出了这些触发器并不符合使用信号增加信息携带量的要求，从而提出了采用多值时钟的并列式多拍多值触发器，并设计了四值Ｄ触发器，这种发器具有存贮能力强，逻辑结构丰富的特点。     

任意值数的时序逻辑电路设计

本文提出了一种值数可任意扩展的多值逻辑存贮单元——DYL多值D触发器。文中将二值时序电路设计方法推广到多值逻辑系统中,运用DYL电路的线性与或门和阈门以及多值D触发器,实现了任意值数的时序逻辑电路设计。     

低功耗四边沿触发器设计

根据在保持电路原有性能的前提下可通过降低时钟频率来降低系统功耗的原理和双边沿触发器的设计思想,本文将多值信号信息量大的优点应用于时钟网络上设计了基于三值时钟的四边沿触发器,消除了三值时钟的冗余跳变,从而通过降低时钟频率的方式达到降低功耗的目的。本文设计的四边沿触发器电路结构简单,既可以用于二值时序电路中也可以用于多值时序电路中。模拟结果表明,本文设计的四边沿触发器具有正确的逻辑功能且能有效地降低系统功耗。     

基于门控时钟技术的低功耗三值D型触发器设计

本文在三值D型触发器的基础上提出了一种低功耗三值门控时钟D型触发器的设计.该设计通过抑制触发器的冗余触发来降低功耗,PSPICE模拟验证了该触发器具有正确的逻辑功能.与三值D触发器相比,该触发器在输入信号开关活动性较低的情况下具有更低的功耗.同时该电路结构可以推广到基值更高的低功耗多值触发器的设计中.     

一种新的ASM设计法

本文提出了用纯二值结构的三值触发器作为基本存贮单元的ASM one-zero-hot设计法。     

三值低功耗多米诺JKL触发器设计及应用

通过对三值触发器和绝热多米诺电路的研究,提出一种新颖低功耗多米诺JKL触发器开关级设计方案。该方案首先利用开关—信号理论,根据三值JKL触发器真值表,推导出三值绝热多米诺JKL触发器开关级结构式;然后利用三值JKL触发器实现三值正循环门电路和三值反循环门电路的设计;最后,经Spice软件模拟证明所设计的三值绝热多米诺JKL触发器逻辑功能正确,与常规三值多米诺JKL触发器相比,能耗节省约69%。     

TWO-INPUT PRESETTING TECHNIQUE AND DESIGN OF CMOS FLIP-FLOPS WITH A HIGH RADIX

By analysing the difficulty of previous flip-flops with a high radix, this paper proposes a logic design scheme with two presetting inputs. The circuit of a quaternary CMOS flip-flop is designed by using the transmission function theory. The result shows that its structure is simpler and its processing speed is higher than that of two binary flip-flops which store the equal information.     

基于数据选择器和D触发器的多输入时序电路设计

为了探索多输入时序逻辑电路的简便实现方法,介绍了基于数据选择器和D触发器的多输入时序逻辑电路设计技术。即将D触发器和数据选择器进行组合,用触发器的现态作为数据选择器选择输入变量、数据选择器的输出函数作为触发器的D输入信号,构成既有存储功能又有数据选择功能的多输入端时序网络。由触发器的现态选择输入变量、所选择的输入变量决定触发器的次态转换方向。该方法适合实现互斥多变量时序逻辑电路,且在设计过程中不需要进行函数化简。     

nMOS四值触发器的设计及其应用

本文应用限幅电压开关理论设计了两种主从型nMOS四值触发器。这砦触发器具有双端预置能力和双轨互补输出。通过采用JKLM型触发器对十六进制加法计数器和十进制加法计数器的设计实例证明了这些触发器能有效地用于四值时序电路的设计。     

新型半静态低功耗D触发器设计

本文从简化触发器内部锁存器结构以降低功耗的要求出发，提出了一种新型的半静态D触发器设计。PSPICE模拟表明，新设计逻辑功能正确。与以往一些设计相比，新设计在功耗和速度上获得显著改进。     

Ultra Low-Power Clocking Scheme Using Energy Recovery and Clock Gating

A significant fraction of the total power in highly synchronous systems is dissipated over clock networks. Hence, low-power clocking schemes are promising approaches for low-power design. We propose four novel energy recovery clocked flip-flops that enable energy recovery from the clock network, resulting in significant energy savings. The proposed flip-flops operate with a single-phase sinusoidal clock, which can be generated with high efficiency. In the TSMC 0.25-$mu$m CMOS technology, we implemented 1024 proposed energy recovery clocked flip-flops through an H-tree clock network driven by a resonant clock-generator to generate a sinusoidal clock. Simulation results show a power reduction of 90% on the clock-tree and total power savings of up to 83% as compared to the same implementation using the conventional square-wave clocking scheme and flip-flops. Using a sinusoidal clock signal for energy recovery prevents application of existing clock gating solutions. In this paper, we also propose clock gating solutions for energy recovery clocking. Applying our clock gating to the energy recovery clocked flip-flops reduces their power by more than 1000 $times$ in the idle mode with negligible power and delay overhead in the active mode. Finally, a test chip containing two pipelined multipliers one designed with conventional square wave clocked flip-flops and the other one with the proposed energy recovery clocked flip-flops is fabricated and measured. Based on measurement results, the energy recovery clocking scheme and flip-flops show a power reduction of 71% on the clock-tree and 39% on flip-flops, resulting in an overall power savings of 25% for the multiplier chip.      

Low power design using double edge triggered flip-flops

In this paper we study the power savings possible using double edge triggered (DET), instead of, conventional single edge triggered (SET) flip-flops. We begin the paper by introducing a set of novel D-type double edge triggered flip-flops which can be implemented with fewer transistors than any previous design. The power dissipation in these flip-flops and single edge triggered flip-flops is compared via architectural level studies, analytical considerations and simulations. The analysis includes an implementation independent study on the effect of input sequences in the energy dissipation of single and double edge triggered flip-flops. The system level energy savings possible by using registers consisting of double edge triggered flip-flops, instead of single edge triggered flip-flops, is subsequently explored. The results are extremely encouraging, indicating that double edge triggered flip-flops are capable of significant energy savings, for only a small overhead in complexity     

An up-transition edge-triggered single-shot pulse generator with Josephson devices

The circuit is constructed with two cross-coupled DC flip-flops, resulting in a square-wave output signal without an external special clock signal. The circuit has been fabricated and its operating margin has been examined. An improved circuit for a wider operating margin is proposed and discussed.     

DESIGN OF nMOS QUATERNARY FLIP-FLOPS AND THEIR APPLICATIONS

By using the theory of clipping voltage-switches, two kinds of master/slave nMOS quaternary flip-flops are designed. These flip-flops have the capability of two-input presetting and double-rail complementary outputs. It is shown that these flip-flops are effectively suitable to design nMOS quaternary sequential circuits by designing two examples of hexadecimal up-counter and decimal up-counter. Supported by Youth Science & Technology Foundation of Ningbo Science & Technology Commission and by Natural Science Foundation of Zhejiang Province, China     

Integration of partial scan and built-in self-test

Partial-Scan based Built-In Self-Test (PSBIST) is a versatile Design for Testability (DFT) scheme, which employs pseudo-random BIST at all levels of test to achieve fault coverages greater than 98% on average, and supports deterministic partial scan at the IC level to achieve nearly 100% fault coverage. PSBIST builds its BIST capability on top a partial scan structure by adding a test pattern generator, an output data compactor, and a PSBIST controller in a way similar to that of deriving a full scan BIST from a full scan structure. However, to make the scheme effective, there is a minimum requirement regarding which flip-flops in the circuit should be replaced by scan flip-flops and/or initialization flip-flops. In addition, test arents are usually added to boost the fault coverage to the range of 95 to 100 percent. These test points are selected based on a novel probabilistic testability measure, which can be computed extremely fast for a special class of circuits. This ciass of circuits is precisely the type of circuits that we obtain after replacing some of the flip-flops.withscan and/or initilization flip-flops. The testability measure is also used for a very useful quick estimation of the fault coverage right after the selection of sean flip-flops, even before the circuit is modified to incorporate PSBIST capability. While PSBIST provides all the benefits of BIST, it incurs lower area overhead and performance degradation than full scan. The area overhead is further reduced when the boundary scan cells are reconfigured for BIST usage.     

A falling edge-triggered single shot pulse generator with Josephson devices

The circuit is constructed with two cross-coupled DC flip-flops, resulting in a square wave output signal without any external special clock signal. The circuit configuration and operating principle are described. The circuit has been experimentally fabricated and its operating margin has been examined. The analysis successfully explains the experimental results.