• 제목/요약/키워드: logic gate delay

검색결과 59건 처리시간 0.028초

기능상 집적된 비포화 논리소자 (Functionally Integrated Nonsaturating Logic Elements)

  • Kim, Wonchan
    • 대한전자공학회논문지
    • /
    • 제23권1호
    • /
    • pp.42-45
    • /
    • 1986
  • This paper introduces novel functionally integrated logic elements which are conceptuallized for large scale integrated circuits. Efforts are made to minimize the gate size as well as to reduce the operational voltage, without sacrificing the speed performance of the gates. The process used was a rather conventional collector diffusion isolation(CDI) process. New gate structures are formed by merging several transistors of a gate in the silicon substrate. Thested elements are CML(Current Mode Logic) and EECL (Emitter-to-Emitter Coupled Logic)gates. The obtained experimental results are power-delay product of 6~11pJ and delay time/gate of 1.6~1.8 ns, confirming the possibility of these novel gate structures as a VLSI-candidate.

  • PDF

병합트랜지스터를 이용한 고속, 고집적 ISL의 설계 (Design of a high speed and high intergrated ISL(Intergrated Schottky Logic) using a merged transistor)

  • 장창덕;이용재
    • 한국정보통신학회:학술대회논문집
    • /
    • 한국해양정보통신학회 1999년도 춘계종합학술대회
    • /
    • pp.415-419
    • /
    • 1999
  • Many bipolar logic circuit of conventional occurred problem of speed delay according to deep saturation state of vertical NPN Transistor. In order to remove minority carries of the base region at changing signal in conventional bipolar logic circuit, we made transistor which is composed of NPN transistor shortened buried layer under the Base region, PNP transistor which is merged in base, epi layer and substrate. Also the Ring-Oscillator for measuring transmission time-delay per gate was designed as well. The structure of Gate consists of the vertical NPN Transistor, substrate and Merged PNP Transistor. In the result, we fount that tarriers which are coming into intrinsic Base from Emitter and the portion of edge are relatively a lot, so those make Base currents a lot and Gain is low with a few of collector currents because of cutting the buried layer of collector of conventional junction area. Merged PNP Transistor's currents are low because Base width is wide and the difference of Emitter's density and Base's density is small. we get amplitude of logic voltage of 200mv, the minimum of transmission delay-time of 211nS, and the minimum of transmission delay-time per gate of 7.26nS in AC characteristic output of Ring-Oscillator connected Gate.

  • PDF

Comparative Study on the Structural Dependence of Logic Gate Delays in Double-Gate and Triple-Gate FinFETs

  • Kim, Kwan-Young;Jang, Jae-Man;Yun, Dae-Youn;Kim, Dong-Myong;Kim, Dae-Hwan
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • 제10권2호
    • /
    • pp.134-142
    • /
    • 2010
  • A comparative study on the trade-off between the drive current and the total gate capacitance in double-gate (DG) and triple-gate (TG) FinFETs is performed by using 3-D device simulation. As the first result, we found that the optimum ratio of the hardmask oxide thickness ($T_{mask}$) to the sidewall oxide thickness ($T_{ox}$) is $T_{mask}/T_{ox}$=10/2 nm for the minimum logic delay ($\tau$) while $T_{mask}/T_{ox}$=5/1~2 nm for the maximum intrinsic gate capacitance coupling ratio (ICR) with the fixed channel length ($L_G$) and the fin width ($W_{fin}$) under the short channel effect criterion. It means that the TG FinFET is not under the optimal condition in terms of the circuit performance. Second, under optimized $T_{mask}/T_{ox}$, the propagation delay ($\tau$) decreases with the increasing fin height $H_{fin}$. It means that the FinFET-based logic circuit operation goes into the drive current-dominant regime rather than the input gate load capacitance-dominant regime as $H_{fin}$ increases. In the end, the sensitivity of $\Delta\tau/{\Delta}H_{fin}$ or ${{\Delta}I_{ON}}'/{\Delta}H_{fin}$ decreases as $L_G/W_{fin}$ is scaled-down. However, $W_{fin}$ should be carefully designed especially in circuits that are strongly influenced by the self-capacitance or a physical layout because the scaling of $W_{fin}$ is followed by the increase of the self-capacitance portion in the total load capacitance.

속도 향상을 위한 병합트랜지스터를 이용한 ISL의 설계 (Design of ISL(Intergrated Schottky Logic) for improvement speed using merged transistor)

  • 장창덕;백도현;이정석;이용재
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 1999년도 춘계학술대회 논문집
    • /
    • pp.21-25
    • /
    • 1999
  • In order to remove minority carries of the base region at changing signal in conventional bipolar logic circuit, we made transistor which is composed of NPN transistor shortened buried layer under the Base region, PNP transistor which is merged in base, epi layer and substrate. Also the Ring-Oscillator for measuring transmission time-delay per gate was designed as well. In the result, we get amplitude of logic voltage of 200mV, the minimum of transmission delay-time of 211nS, and the minimum of transmission delay-time per gate of 7.26ns in AC characteristic output of Ring-Oscillator connected Gate.

  • PDF

ED MOS 논리 LSI 의 지연시간 모델링과 디자인 논리 시뮬레이터 (Delay Time Modeling for ED MOS Logic LSI and Multiple Delay Logic Simulator)

  • 김경호;전영준;이창우;박송배
    • 대한전자공학회논문지
    • /
    • 제24권4호
    • /
    • pp.701-707
    • /
    • 1987
  • This paper is concerned with an accurate delay time modling of the ED MOS logic gates and its application to the multiple delay logic simulator. The proposed delay model of the ED MOS logic gate takes account of the effects of not only the loading conditions but also the slope of the input waveform. Defining delay as the time spent by the current imbalance of the active inverter to charge and discharge the output load, with respect to physical reference levels, rise and fall model delay times are obtained in an explicit formulation, using optimally weighted imbalance currents at the end points of the voltage transition. A logic simulator which uses multiple rise/fall delays based on the model as decribed in the above has been developed. The new delay model and timing verification method are evaluated with repect to delay accuracy and execution time.

  • PDF

상위단계 설계 검증을 위한 논리/타이밍 추출 시스템의 설계 (Design of A Logic/Timing Extraction System for Higher-level Design Verification)

  • 이용재;문인호;황선영
    • 전자공학회논문지A
    • /
    • 제30A권2호
    • /
    • pp.76-85
    • /
    • 1993
  • This paper describes the design of a technology-independent logic, function, and timing extraction system from SPICE-like network descriptions. Technology-independent extraction mechanism is provided in the form of technology files containing the rules for constructing logic gates and functional blocks. The designed system can be more effectively used in cell-based design by describing the cells to be extracted. Timing extraction is performed by using a linear RC gate delay model which takes interconnection delay into account. Experimental results show that estimated delay is within 10 percents for logic gate circuits when compared with SPICE. Through higher-level design descriptions obtained by extraction, design cycles can be considerably reduces.

  • PDF

새로운 고속의 NCL 셀 기반의 지연무관 비동기 회로 설계 (Delay Insensitive Asynchronous Circuit Design Based on New High-Speed NCL Cells)

  • 김경기
    • 한국산업정보학회논문지
    • /
    • 제19권6호
    • /
    • pp.1-6
    • /
    • 2014
  • 지연 무관방식의 NCL 비동기 설계는 혁신적인 비동기 회로 설계 방식의 하나로써 견고성, 소비전력 그리고 용이한 설계의 재사용과 같은 많은 장접을 가지고 있다. 그러나, 기존의 NCL 게이트 셀들의 트랜지스터-레벨 구조들은 느린 스피드, 높은 영역 오버헤드, 높은 와이어(wire) 복잡도와 같은 약점 또한 가지고 있다. 따라서, 본 논문에서는 빠른 스피드, 낮은 영역 오버헤드, 낮은 와이더 복잡도를 위해서 트랜지스터 레벨에서 설계된 새로운 고속의 NCL 게이트 셀을 제안하고자 한다. 제안된 고속의 NCL 게이트 셀들은 회로 지연, 영역, 소모 전력에 의해서 기존의 다른 NCL 게이트 셀들과 비교되었다..

드모르간 및 재대입 변환의 경로지연고장 테스트집합 유지 (Path Delay Test-Set Preservation of De Morgan and Re-Substitution Transformations)

  • 이준환;이현석
    • 대한전자공학회논문지SD
    • /
    • 제47권2호
    • /
    • pp.51-59
    • /
    • 2010
  • 드모르간 및 재대입 논리변환은 unate gate network (UGN)을 보다 일반적인 balanced inversion parity (BIP) network으로 전환하는데 충분하다. 이러한 회로계층에 대해서도 자세히 논의하고 있다. 우리는 드모르간 및 재대입 논리변환이 경로지연고장 테스트집합을 유지한다는 것을 증명하였다. 본 논문의 결과를 이용하여 함수 z를 구현하는 모든 UGN에서 모든 경로지연고장을 검출하는 상위수준 테스트집합은 함수 z의 어떠한 BIP realization에서도 모든 경로지연고장을 검출한다는 것을 보일 수 있다.

타이밍 최적화 기술 매핑 시스템의 설계 (Design of a Time Optimaized Technology Mapping System)

  • 이상우;황선영
    • 전자공학회논문지A
    • /
    • 제31A권4호
    • /
    • pp.106-115
    • /
    • 1994
  • This paper presents the design of a technology mapping system for optimizing delays of combinational and synchronous sequential logic circuits. The proposed system performs delay optimization for combinational logic circuits by remapping, buffering, and gate merging methods through the correct delay calculation in which the loading values are considered. To get time optimized synchronous sequential circuits, heuristic algorithms are proposed. The proposed algorithms reallocate registers by considering the critical path characteristics. Experimental results show that the proposed system produces a more optimized technology mapping for MCNC benchmarks compared with mis-II.

  • PDF

A Study on the Exclusive-OR-based Technology Mapping Method in FPGA

  • Ko, Seok-Bum
    • 한국통신학회논문지
    • /
    • 제28권11A호
    • /
    • pp.936-944
    • /
    • 2003
  • 본 논문에서는 FPGA (Field Programmable Gate Array)에 사용될 수 있는 AND/XOR기반의 기술적인 매핑 기법이 제안되었다. FPGA에서는 프로그램 블록들의 숫자가 정해져 있기 때문에 적절한 수의 입력을 가진 블록으로 회로를 나눌 수 있으면 효과적인 구현이 가능하다. Davio Expansion에 기반한 제안된 기법은 Davio Expansion 자체가 AND/XOR의 성질을 가지고 있기 때문에 XOR를 많이 포함하고 있는 에러 검출/수정, 데이터 암호/해독, 산술 회로 등을 구현하기 매우 용이하다. 본 논문에서는 제안된 기법을 이용할 때 구현되는 면적뿐만 아니라 속도도 현저히 저하될 수 있음을 MCNC 벤치마크를 이용하여 증명하였다. 면적이 줄어듦을 보이기 위하여 CLB (Configurable Logic Block) 숫자와 총 게이트 숫자가 이용되었다. CLB 숫자는 67.6 % (속도로 최적화 된 결과)와 57.7 % (면적으로 최적화 된 결과) 만큼 감소되었고 총 게이트 숫자는 65.5 %만금 감소되었다. 속도관련 결과를 확인하기 위해 사용된 최대 Path Delay는 현재 사용되고 있는 방법들에 비해 56.7 %만큼 감소되었고 최대 Net Delay는 80.5% 만큼 감소되었다.