• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.31 no.8
• /
• pp.826-832
• /
• 2007

Fully flexible cell preserves Hamiltonian in structure so that the symplectic time integrator is applicable to the equations of motion. In the direct formulation of fully flexible cell N-Sigma-T ensemble, a generalized leapfrog time integration (GLF) is applicable for fully flexible cell simulation, but the equations of motion by GLF has structure of implicit algorithm. In this paper, the time integration formula is derived for the fully flexible cell molecular dynamics simulation by using the splitting time integration. It separates flexible cell Hamiltonian into terms corresponding to each of Hamiltonian term. Thus the simple and completely explicit recursion formula was obtained. We compare the performance and the result of present splitting time integration with those of the implicit generalized leapfrog time integration.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.6 no.6
• /
• pp.891-896
• /
• 2002

In this paper, a new voltage-controlled tunable integrator for low-voltage applications is proposed. The proposed active element is composed of the CMOS complementary cascode circuit which can extend transconductance of an element. Therefore, the unity gain frequency which is determined transcon-ductance is increased than that of the conventional element. And then these results are verified by the $0.25{\mu}m$ CMOS n-well parameter HSPICE simulation. As a result, the gain and the unity gain frequency are 42dB and 200MHz respectively in the element on 2V supply voltage. And power dissipation of the designed circuit is 0.32mW.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.25 no.10B
• /
• pp.1785-1792
• /
• 2000

In this paper multi-rate non-recursive architecture for CIC(Cascaded Integrator-Comb) decimation filters with an arbitrary factor is proposed. The CIC filters are widely used in high speed wireless communication systems since they have multiplier-less and multi-rate low-power structure. Even conventional non-recursive CIC structure is multi-rate this architecture can be structured only in case of M-th power-of-two decimation factor. This paper proposes that muli-rate non-recursive CIC architecture can be structured with an any decimation factor of product form. Power consumption of the proposed architecture is compared with that of the conventional non-recursion architecture.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.21 no.7
• /
• pp.1726-1733
• /
• 1996

A 3V-50MHz analog CMOS continuous-time current-mode filter with a negative resistance load(NRL) is proposed. In order to design a current-mode current integrator, a modified basic current mirror with a NRL to increase the output resistance is employed. the inherent circuit structure of the designed NRL current integrator, which minimizes the internal circuit nodes and enhances the gain bandwidth product, is capable of making the filter operate at the high frequency. The third order Butterworth low pass filter utilizing the designed NRL current integrator is synthesized and simulated with a 1.5.mu.m CMOS n-well proess. Simulation result shows the cutoff frequency of 50MHz and power consumption of 2.4mW/pole with a 3V power supply.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.60 no.4
• /
• pp.871-876
• /
• 2011

In this paper, a voltage-controlled frequency tunable current-mode integrator and a 3rd-order current-mode Chebyshev filter in 1.8V-$0.18{\mu}m$ CMOS is realized for software radio applications in system-on-chips. This filter is used for reconstruction purposes between a current-steering DAC and a current-mode mixer. Power consumption of the designed filter can be reduced by using a current-mode small size integrator. And also, cutoff frequency of this filter is variable between 1.2MHz and 10.1MHz, the power consumption is 2.85mW. And the voltage bias compensated circuit is used to control the voltage variation.in the designed filter.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.23 no.3
• /
• pp.409-414
• /
• 1986

To eliminate the requirement of multiplications in nonrecursive filter realization, the use of a delta modulation(DM) has been studied by several researchers. However, the structure of DM filters inevitably contains an intergrator that is cascaded with the arithmetic unit to operate convolution summation. In this paper we porpose a method to determine the coefficients that may be used for implementation of a DM filter without an integrator. Also, we obtain the condition by which one can exclude the response errors due to the elimination of the integrator. By computer simulations it is shown that the performance of the proposed filter is very good, providing that the condition is satisfied.

• Proceedings of the KIEE Conference
• /
• 1988.11a
• /
• pp.465-468
• /
• 1988

A n-well CMOS Operational Transconductance Amplifier -C(OTA-C) integrator with a wide linear input range is designed. The circuit designed has superior linearity of input voltage range compared with the conventional source-coupled pair OTA. The OTA developed in this paper is versatile in application: diverse applications are in the fields of linear amplifiers, continuous-time filters, gain control circuits, and analog multipliers, etc..

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.15 no.4
• /
• pp.20-25
• /
• 1978

Two augmented integrators are sufficient as memory elements to realize an arbitrary second-order voltage transfer funtion which has complex poles in left-half S-plane, where S is a complex variable. The augmented integrator is characterized by transfer funtion B/(S+A), where A and B are real constant.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.237-237
• /
• 2000

In this paper, The modified dead-time compensator for plants with an integrator and long dead time is proposed. The design procedure takes account of the closed-loop performance and robustness. The tuning of the controller can be done using some information about the plant and its uncertainties. The proposed controller is compared to others recently presented in the literature. Some simulation results verify good closed-performance and robustness of the proposed DTC.

• Proceedings of the KIEE Conference
• /
• 1998.07a
• /
• pp.61-63
• /
• 1998

A B-H curve measuring system for testing softmagnetic materials was constructed. This system can measure the B-H curve in the low frequency(0.1 - 1 Hz) range. The drift of the integrator can be moderately removed by software technique. The advantages of the developed system are easier to measure B-H curve compared with conventional measuring system and low cost.