• The Journal of the Korea institute of electronic communication sciences
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• v.3 no.2
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• pp.79-85
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• 2008

It is important to consider the life of battery and low power operation for various wireless communications. Thus, Analog current-mode signal processing with SI circuit has been taken notice of in designing the LSI for wireless communications. However, in current mode signal processsing, current memory circuit has a problem called clock-feedthrough. In this paper, we examine the connection of CMOS switch that is the common solution of clock-feedthrough and calculate the relation of width between CMOS switch for design methodology for improvement of current memory. As a result of simulation, when the width of memory MOS is 20um, ratio of input current and bias current is 0.3, the width relation in CMOS switch is obtained with $W_{Mp}=5.62W_{Mn}+1.6$, for the nMOS width of 2~6um in CMOS switch. And from the same simulation condition, it is obtained with $W_{Mp}=2.05W_{Mn}+23$ for the nMOS width of 6~10um in CMOS switch. Then the defined width relation of MOS transistor will be useful guidance in design for improvement of current memory.

• Journal of information and communication convergence engineering
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• v.10 no.1
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• pp.85-90
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• 2012

A 40-MS/sec 10-bit pipelined analog to digital converter (ADC) with a 1.2 Vpp differential input signal is proposed. The implemented pipelined ADC consists of eight stages of 1.5 bit/stage, one stage of 2 bit/stage, a digital error correction block, band-gap reference circuit & reference driver, and clock generator. The 1.5 bit/stage consists of a sub-ADC, digital to analog (DAC), and gain stage, and the 2.0 bit/stage consists of only a 2-bit sub-ADC. A bootstrapped switch with a constant resistance is proposed to improve the linearity of the input switch. It reduces the maximum VGS variation of the conventional bootstrapped switch by 67%. The proposed bootstrapped switch is used in the first 1.5 bit/stage instead of a sample-hold amplifier (SHA). This results in the reduction of the hardware and power consumption. It also increases the input bandwidth and dynamic performance. A reference voltage for the ADC is driven by using an on-chip reference driver without an external reference. A digital error correction with a redundancy is also used to compensate for analog noise such as an input offset voltage of a comparator and a gain error of a gain stage. The proposed pipelined ADC is implemented by using a 0.18-${\mu}m$ 1- poly 5-metal CMOS process with a 1.8 V supply. The total area including a power decoupling capacitor and the power consumption are 0.95 $mm^2$ and 51.5 mW, respectively. The signal-to-noise and distortion ratio (SNDR) is 56.15 dB at the Nyquist frequency, resulting in an effective number of bits (ENOB) of 9.03 bits.

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.625-628
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• 1989

광섬유와 micro변형기를 이용하여 다점 압력 계측 system을 구성하여 실험을 행하였다. 그 결과 pulse generator와 analog switch를 이용함으로써 100ns의 광 pulse를 쉽게 얻을 수 있었으며, 또한 3개의 광 pulse를 analog switch를 이용하여 쉽게 분리할 수 있었다. 한편 변형기에 가한 힘과 광 손실간의 상관관계를 이론치와 비교하여 조사한 결과 힘과 광손실간의 상관관계는 이론치와 실험치가 유사한 경향을 나타내는 것을 알 수 있었다.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.212-214
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• 2005

The charge-pump circuit which is used to generate higher voltage than the available supply voltage has wide applications such as the flash memory of EEPROM Because the demand for high voltage comes from physical mechanism such as the oxide tunneling, the required pumped voltage cannot be scaled as the power supply voltage is scaled. Therefore, an efficient charge-pump circuit that can achieve high voltage from the available low supply voltage is essential. A new Analog Switch p-well CMOS charge pump circuit without the MOS device body effect is processed. By improve the structure of the circuit's transistors to reduce the threshold voltage shift of the devices, the threshold voltage of the device is kept constant. So, the circuit electrical characteristics are higher output voltage within a shorter time than the conventional charge pump. The propose analog switch CMOS charge pump shows compatible performance of the ideal diode or Dickson charge pump.

• Journal of information and communication convergence engineering
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• v.9 no.1
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• pp.74-77
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• 2011

PSPICE modeling of a commercial LED driver IC (TOP245P) and PC817A optocoupler is proposed for the switch-mode power supply (SMPS) (applicable to LED driver) design and simulation. An analog behavioral model of the TOP245P IC including the shunt regulator, under-voltage(UV) detection, over-voltage(OV) shut-down and SR flip-flop is developed by using PSPICE. The empirical equation of PC817A current transfer ratio (CTR) is fitted from the datasheet of PC817A. Two types of SMPSs are simulated with the averaged-model and switching-model. The simulation results by the proposed PSPICE models are in good agreement with those in the data sheet and an experimental data.

• The Transactions of the Korean Institute of Power Electronics
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• v.19 no.2
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• pp.133-138
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• 2014

This paper proposes a low power-loss averaging current mode control using a resistor and bypass switch. Generally, current sensing method using a resistor has a disadvantage of power loss which degrades the efficiency of the entire systems. On the other hand, proposed measurement technique operating with bypass-switch connected in parallel with sensing resistor can reduce power loss significantly the current sensor. An analog-circuited bypass driver is implemented and used along with an average-circuit mode controller. The bypass switch bypasses the sensing current with a small amount of power loss. In this paper, a 50[W] prototype average current mode boost converter has been implemented for the experimental verification.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.8
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• pp.1827-1832
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• 2014

In this thesis, we use one by one each of the analog switch and a high-speed DAC instead of the DAC that two or more are used in transmitting and receiving antennas multiple systems, maintaining the advantages of the existing method, reducing design costs, physical to provide a method that can reduce the data converters from MIMO system can improve the economic efficiency and the size reduction of a basis.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2007.04a
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• pp.485-488
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• 2007

최근 Analog Sampled-Data 신호처리를 위하여 주목되고 있는 SI(Switched-Current) circuit은 저전력 동작을 하는 장점이 있지만, 반면에 SI circuit에서의 기본 회로인 Current Memory는 Charge Injection에 의한 Clock Feedthrough이라는 치명적인 단점을 갖고 있다. 따라서 본 논문에서는 Current Memory의 문제점인 Clock Feedthrough의 일반적인 해결방안으로 Dummy Switch의 연결을 검토하였고, Austria Mikro Systeme(AMS)에서 $0.35{\mu}m$ CMOS process BSIM3 Model로 제작하기 위하여 Current Memory의 Switch MOS와 Dummy Switch MOS의 적절한 Width을 정의하여야 하므로, 그 값을 도출하였다. Simulation 결과, Switch의 Width는 $2{\mu}m$, Dummy Switch의 Width는 $2.35{\mu}m$로 정의될 수 있음을 확인하였다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.3
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• pp.145-153
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• 2016

Cable TV with largest subscription base in pay TV market has difficulty in managing the task of digital switch over. This study analyzed the factors in delay of cable TV switch over and examined the impact of pay TV market structure and competition. The delaying factors turned out to be the lack of incentives and resources of cable TV operators, insufficient policy measures and acceptance tolerance issues of subscribers. Since cable TV operators with monopolistic status in pay TV market had continuous profit from analog service, they were not responsive to digital switch over which requires additional investment. Policy measures including support for the low income household and mandatory cut-off point for stopping analog broadcasting. Subscriber's willingness to accept digital broadcasting in terms of price sensitivity and preference for convenient operation also played a role. Introduction of IPTV in pay TV market influenced the speed of digital switch over of cable TV operators. MSOs with economies of scale showed higher digital switch over rate than independent SO.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.446-448
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• 2001

We have developed the testing software for KEPCO operators to maintain the small-scale distribution automation system effectively. The testing software is used to monitor the present status, to measure the analog value(voltage, amperage) and to control the switch and FRTU(Feeder Remote Terminal Unit) in order to find out a disabled part of the system. And at the stage of inspection of the switch and FRTU, it can screen the inferior one.