미세결함 검출용 초저전력 자동 이득 조절 증폭기 구현

Abstract

Abstract A Programmable Gain Amplifier(PGA) is an operational amplifier that allows the controller to adjust its transfer signals so as to provide larger or smaller voltage gain. In general, it is essential to maximize the range of dynamic output signals related to the given input signals in the analog systems. This thesis presents the design of a new ultra low-power PGA to detect all types of micro inner defects in the process of producing steel plates. The proposed PGA consists of 3 stages such as the PGA core with active load, the feedback system, the common source amplifier, etc. To achieve low-power consumption and an accurate system, the PGA is based on using digital control CMOS switches and passive resistors at the first stage. The second stage also contains the feedback system to increase system ability. Moreover, the proposed PGA has fully symmetric scheme to reduce the input and power supply noises in the detected signal containing defects. The proposed PGA is fabricated using a Magnachip/SK Hynix 0.18μm CMOS 1poly-6metal technology. Its performance is validated by simulation using Advanced Design System. According to our simulation results, the proposed PGA showed an excellent gain error of less than 0.12dB, a very small chip size of 0.015mm, and ultra low-power consumption of 0.19mW as compared to conventional results. These results reveal that the proposed PGA has ultra low-power consumption and very small gain error.