• Journal of Industrial Technology
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• v.13
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• pp.59-69
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• 1993

Using two current conveyors with the grounded capacitors and resistors, this paper proposed equivalent circuits which can realize the floating L and the floating FDNR. To find out their characteristics, we experiment with these circuits instead of the floating L of the low-pass filter and the floating FDNR of the high-pass filter respectively. Comparing theoretical values with experimental ones, values of the proposed floating L represent the error of 5 percents in the frequency range from 5 KHz to 25 KHz, and values of the floating FDNR represent the error of 5 percents in the range from 8 KHz to 25 KHz. So the proposed floating L and the FDNR circuits are expected to be implemented with current conveyors of an IC.

• Journal of the Microelectronics and Packaging Society
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• v.19 no.4
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• pp.33-37
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• 2012

Microstructure developments of $RuO_2$ based thick film resistors during firing as a function of glass viscosity were analytically quantified and its effect on the electrical property was investigated. The microstructure development was retarded as the viscosity of glass was increased. It was found that the viscosity range for each stage of microstructure development are as follows ; $7500-10^5Pa{\cdot}s$ for the glass sintering, $2000-7500Pa{\cdot}s$ for the glass island formation, $700-2000Pa{\cdot}s$ for the glass spreading, and $50-700Pa{\cdot}s$ for the infiltration. The sheet resistivity decreased as the viscosity of glass in the resistor film increased due to the higher chance of sintering for the conductive particles with the higher viscosity of the glass.

• Journal of information and communication convergence engineering
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• v.18 no.3
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• pp.201-206
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• 2020

This paper presents a new method for controlling the current of lighting LEDs without current sensors. This method can be used as backup against LED current sensor faults. LED lighting requires a circuit with a constant current in order to maintain the same brightness when the ambient temperature changes. Therefore, we propose a new current estimation method to provide backup in case of current sensor faults based on the calculation of the inductor current. In the fabricated circuit, the average current changes from 144.03 mA to 155.97 mA when the ambient temperature changes from 0℃ to 60℃. The application of this study can enable the fabrication of a driving IC for LEDs in the form of a single chip without sensing resistors. This is expected to reduce the complexity of the peripheral circuit and enable precise feedback control.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.55 no.9
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• pp.472-477
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• 2006

This paper presents a new voltage/current mixed method for driving synchronous rectifiers (SR) adapted to the flyback topology. The synchronous rectifier driven by the proposed voltage/current mixed method can operate at a wide load range with high efficiency. The gate voltage of MOSFET in the synchronous rectifier can be easily controlled by changing the ratio of resistors, irrespective of a line and load fluctuation. A 200W (12V/17A) prototype converter was built and an efficiency of 93% was measured at 10A load current.

• Electrical & Electronic Materials
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• v.8 no.1
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• pp.27-34
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• 1995

The analysis of nonlinear equivalent circuit and the resonance characteristics of input current and output voltage were simulated, and their electrical properties are discussed in the transverse-type piezoelectric ceramic transformer. The nonlinear resonance characteristics of input current and output voltage showed by the thermal effect due to a higher driving current, the nonlinearity increased greatly as driving current increased. When load resistor was 100[M.ohm.], the nonlinear coefficient was -1.3. The nonlinear resonance curve of input current and output voltage for a variation of input voltage and load resistor agreed with the discussed theory. The output voltage increased nearly proportioned to input voltage when load resistors were below 50[M.ohm.], the voltage step-up ratio decreased when a load resistor was 100[M.ohm.] and their maximum value was 950.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.4
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• pp.1-8
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• 1998

An MMIC single-balanced upconverting mixer for PCS application has been successfully developed using an MMIC process employed by 1 .mu. ion implanted GaAs MESFET and passive lumped elements consisting of spiral inductor, Si3N4 MIM capacitors and NiCr resistors. The configuration of the mixer presented in this paper is two balanced cascode FET mixers with common-source self-bias circuits for single power supply operation. The dimension of the fabricated circuit including two active baluns intermodulation characteristic with two-tone excitation are also measured, showing -28.17 dBc at IF power of -30 dBm.

• ETRI Journal
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• v.29 no.4
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• pp.470-476
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• 2007

In this paper, a versatile three-input five-output universal capacitor-grounded voltage-mode filter is proposed. The circuit employs two differential voltage current conveyors as active elements together with two grounded capacitors and four resistors as passive elements. The proposed configuration can be used as either a single-input five-output or three-input two-output. Unlike the previously reported works, it can simultaneously realize five different generic filtering signals: lowpass, bandpass, highpass, bandreject, and allpass. It still maintains the following advantages: (i) the employment of all grounded capacitors, (ii) no need to employ inverting-type input signals, (iii) no need to impose component choice, (iv) orthogonal control of the resonance angular frequency ${\omega}_o$ and the quality factor Q, and (v) low active and passive sensitivity performances.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.6
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• pp.969-974
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• 1987

High value sheet resistance (Rs, 350 \ulcorner/ -80 K \ulcorner/ ) borom implanted polysilicon resistors were fabricated under process condition compatible with bipolar integrated circuits fabrication. This paper includes the effect of contact ion implantation on Rs and the effect of electron gun(e-gun) deosition vs. non e-gun evaporated metal contacts on the Rs. From results, we observed that the contact ion implanted samples showed higher Rs value than those without contact ion implantation. Also, it was shown that there is noticeable amount of Rs degradation for e-gun samples, while sputtered samples expressed little Rs degradation after PtSi was formed.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.4
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• pp.42-50
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• 2003

This paper presents an embedded RC oscillator which has temperature compensation circuits. The conventional RC oscillator has frequency deviation about 15%, which is caused by variation of resistors and the reference voltage of schmitt trigger from the temperature condition. In this paper, the proposed circuit use a CMOS bandgap reference having balanced current temperature coefficients as a triggering voltage of schmitt trigger. The constant current sources consist of current mirror circuit with the positive and negative temperature coefficient. The proposed circuit shows less 3% frequency deviation for variation of temperature, supply voltage and process parameters.

• Proceedings of the IEEK Conference
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• 2001.06b
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• pp.89-92
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• 2001

In this paper, a simple low-power CMOS current reference circuit is proposed. The reference circuit includes parasitic pnp BJTs and resistors. Temperature compensation is made by adding a current component proportional to a thermal voltage to a current component proportional to a base-to-emitter voltage. The designed circuit has been simulated using a 0.25${\mu}{\textrm}{m}$ n-well CMOS process parameters. The simulation results show that the reference current is 34.96$mutextrm{A}$$\pm$0.04$mutextrm{A}$ in the temperature range of -2$0^{\circ}C$ to 12$0^{\circ}C$ The reference current varies less than 0.6% when the power supply voltage changes from 2.5V to 3.5V For $V_{DD=5V}$ and T=3$0^{\circ}C$ the power consumption is 520㎼ during normal operation but reduces to 0.l㎻ during power-down mode.