Jung S.-M.,Hanshin University
Journal of Next Generation Information Technology | Year: 2013
This paper proposes an active capacitive sensing circuit for fingerprint sensors, which includes a pixel level charge-sharing and charge pump to replace an ADC. This paper also proposes the operating algorithm for 16-level gray scale image. The active capacitive technology is more flexible and can be adjusted to adapt to a wide range of different skin types and environments. The proposed novel circuit is composed with unit gain buffer, 6-stage charge pump and analog comparator. The proper operation is validated by the HSPICE simulation of one pixel with condition of 0.35μm typical CMOS parameter and 3.3V power.
Yeo H.,Hanshin University
International Journal of Multimedia and Ubiquitous Engineering | Year: 2016
This paper proposes a pipelined scan driver architecture for a fingerprint sensor based on an integrator. The proposed pipelined scan driver secures enough time to integrate sensor signals of a fingerprint sensor because a fingerprint sensor based on an integrator requires a large number of clocks to get sensor signals of reasonable SNR. Therefore, the proposed pipelined scan driver reduces an overall image capture time effectively without performance degradation by integrating the sensor signals for several sensor cells simultaneously. A prototype 88x2 array fingerprint sensor combined with the proposed pipelined scan driver were designed in this paper. The implemented pipelined scan driver was simulated with Verilog HDL for the functional verification. The 88x2 fingerprint sensor with a synthesized pipelined scan driver were implemented and simulated using a standard 0.18μm CMOS technology. The simulation results were presented and analyzed in this paper. © 2016 SERSC.
Jung S.,Hanshin University
International Journal of Bio-Science and Bio-Technology | Year: 2016
A FPGA implementation of fingerprint sensors scheme is described for removing parasitic offset image on no touch. This paper proposes an effective fingerprint identification system with 160×192 array fingerprint sensor hardware. The proposed calibration scheme initializes a fingerprint sensor LSI to eliminate the influence of offset image by the electrical characteristic difference of pixel array, which is degraded during long-time use. Each step of a fingerprint algorithm is analyzed based on FPGA. This paper designs an effective hardware scheme for using the Verilog-HDL in 160×192 pixel array. The circuit includes 3 memorys and control logic. The function is verified in RTL simulation and FPGA logic synthesis. © 2016 SERSC.
Jeong T.,Hanshin University
Physica B: Condensed Matter | Year: 2012
The Heusler compound Mn 3Si, the antiferromagnet in the Mn-based class of Heuslers which contains several conventional and half-metallic ferromagnet, shows a peculiar stability of its magnetic order in high magnetic fields. We investigated the electronic and magnetic properties of Mn 3Si by band structure calculations based on the density functional theory. The minority bands of Mn 3Si in the spin polarized state are gapped at the Fermi level, which shows a half-metallic behavior of Mn 3Si. © 2011 Elsevier B.V.All rights reserved.
Jeong T.,Hanshin University
Solid State Communications | Year: 2010
We investigated the electronic properties of CeIrSi3 using density functional theory. The electronic structure of CeIrSi3 was calculated with the spin-orbit interactions and the on-site Coulomb potential for the Ce-derived 4f orbitals. The Ce 4f bands are located near the Fermi level. The fully relativistic band structure scheme shows that the spin-orbit coupling splits the 4f states into two manifolds. It was found that the total number of DOS at the Fermi level by the fully relativistic scheme corresponds to the large electronic specific heat coefficient γb = 9.88 mJ/K2 mol and underestimates the experiment value by a factor of 12.1. © 2009 Elsevier Ltd. All rights reserved.
Lee H.,Chung - Ang University |
Seo S.,Chung - Ang University |
Ryoo S.,Hanshin University |
Yoon K.,Chung - Ang University
NPAR Symposium on Non-Photorealistic Animation and Rendering | Year: 2010
A texture transfer algorithm modifies the target image replacing the high frequency information with the example source image. Previous texture transfer techniques normally use such factors as color distance and standard deviation for selecting the best texture from the candidate sets. These factors are useful for expressing a texture effect of the example source in the target image, but are less than optimal for considering the object shape of the target image. In this paper, we propose a novel texture transfer algorithm to express the directional effect based on the flow of the target image. For this, we use a directional factor that considers the gradient direction of the target image. We add an additional energy term that respects the image gradient to the previous fast texture transfer algorithm. Additionally, we propose a method for estimating the directional factor weight value from the target image. We have tested our algorithm with various target images. Our algorithm can express a result image with the feature of the example source texture and the flow of the target image. © 2010 ACM.
Yeo H.,Hanshin University
Journal of Next Generation Information Technology | Year: 2014
This paper analyzes and compares four different types of capacitive sensor based on charge transfer circuit. The sensors are based on a passive charge transfer circuit, a parasitic-sensitive discrete-time integrator, a parasitic-insensitive discrete time integrator, and a passive-style charge transfer circuit with active output voltage feedback. To verify the theory, a simple lumped and a 20x20 cell touch screen panels modeled with RC circuits are used in simulation. A touch cell with 20% of capacitance variation between touch and non-touch states is assumed for the simulation. The performances of four sensors were simulated with standard 0.35μm CMOS technology. From the simulation results, a sensor based on passive charge transfer can be properly used in both self and mutual capacitive sensing. A sensor based on parasitic-insensitive integrator can be used effectively in mutual capacitive sensing by eliminating parasitic capacitance effect. A sensor based on passive-style charge transfer circuit with active output voltage feedback can be used in mutual capacitive sensing for best performance with minimum parasitic capacitance effect.
Yeo H.,Hanshin University
International Journal of Bio-Science and Bio-Technology | Year: 2015
This paper proposes a fingerprint sensor cell and driver architecture based on a charge integration scheme. The fingerprint sensor cell uses an active output voltage feedback (AOVF) integrator as a capacitance-to-voltage converter. A multiple integration scheme is suggested to improve signal-to-noise ratio (SNR) and amplify the sensing signal, which enables a simple and robust fingerprint sensor driver architecture. A prototype fingerprint sensor array of 1x64 is implemented with an AOVF integrator. The performances of the proposed fingerprint sensor were simulated with standard 0.35μm CMOS technology. By simulations, the proposed fingerprint sensor senses even sub-femto farad differences and has large sensing voltage range. © 2015 SERSC.
Hanshin University | Date: 2014-07-31
A charge transfer circuit for capacitive sensing is disclosed. The charge transfer circuit for capacitive sensing includes a variable capacitor, an X-drive unit, and an active output voltage feedback (AVF) part. The variable capacitor is disposed between the output terminal of an X-drive line and the input terminal of a Y-drive line. The X-drive unit is connected between the input unit of the X-drive line and a voltage input terminal. The active output voltage feedback (AVF) part is connected between the output terminal of the Y-drive line and a voltage output terminal. The output terminal of the AVF part is connected to the output terminal of the Y-drive line.
Kaonmedia Co. and Hanshin University | Date: 2014-04-30
The present invention relates to a technology based on memory sharing technique for processing piping format broadcast signal. More specifically, the present invention relates to a technology for a digital broadcast receiver (e.g., set-top boxes) to efficiently process DVB-T2/S2/C2 piping format broadcast signal which is a next-generation European digital television standard with lowering system load of the receiver by memory sharing technique. In the present invention, it is identified in view of transmission media between File mode of reading data files and Ethernet mode of playing broadcast stream in a real-time manner through Ethernet. Further, Normal Mode (NM) or High-Efficiency Mode (HEM) is identified in view of data field format. The present invention may be implemented in a form of application software on a general purpose operating system (OS).