دانلود رایگان ترجمه مقاله 1.2V بهبود یافته عملیاتی برای برنامه های زیست پزشکی – 2012
دانلود رایگان مقاله انگلیسی یک تقویت کننده عملیاتی بهبود یافته 1.2V برای کاربردهای زیست پزشکی به همراه ترجمه فارسی
عنوان فارسی مقاله | یک تقویت کننده عملیاتی بهبود یافته 1.2V برای کاربردهای زیست پزشکی |
عنوان انگلیسی مقاله | A 1.2V improved operational amplifi er for bio-medical applications |
رشته های مرتبط | مهندسی برق، پزشکی، مهندسی الکترونیک، مدارهای مجتمع الکترونیک، سیستمهای الکترونیک دیجیتال، زیست پزشکی |
کلمات کلیدی | تقویت کننده عملیاتی، زیست پزشکی، قدرت پایین، نویز پایین |
فرمت مقالات رایگان |
مقالات انگلیسی و ترجمه های فارسی رایگان با فرمت PDF آماده دانلود رایگان میباشند همچنین ترجمه مقاله با فرمت ورد نیز قابل خریداری و دانلود میباشد |
کیفیت ترجمه | کیفیت ترجمه این مقاله متوسط میباشد |
مجله | مجله بین المللی مهندسی پزشکی و تکنولوژی – International Journal of Biomedical Engineering and Technology |
سال انتشار | 2012 |
کد محصول | F854 |
مقاله انگلیسی رایگان (PDF) |
دانلود رایگان مقاله انگلیسی |
ترجمه فارسی رایگان (PDF) |
دانلود رایگان ترجمه مقاله |
خرید ترجمه با فرمت ورد |
خرید ترجمه مقاله با فرمت ورد |
جستجوی ترجمه مقالات | جستجوی ترجمه مقالات مهندسی برق |
فهرست مقاله: چکیده |
بخشی از ترجمه فارسی مقاله: 1. مقدمه |
بخشی از مقاله انگلیسی: 1 Introduction Currently, there is an ever-growing demand for low-power and low-noise mixed signal integrated circuits, in portable medical systems. So, a high level of system integration is required to handle bio-potential system. The most commonly observed bio-potentials used for medical diagnoses are monitored non-invasively with electrodes placed on the surface of the skin (Lee et al., 2006a, 2006b). These include the Electrocardiogram (ECG), which monitors heart activity; the Electromyogram (EMG), which monitors other muscle activity in the body, and the Electroencephalolgram (EEG), which monitors electrical activity in the brain via weak potentials on the scalp. Several approaches are carried out to integrate analogue front-end using CMOS technology. Generally, the integrated chip offers a relatively low-cost product for both ECG and EEG signals, but with high-power consumption. To overcome this problem, programmable components with adjustable trade-off between noise and power dissipation are embedded in the same chip. Since the main noise source in the recording chain of bio-medical signals is found in the fi rst component, i.e., the preamplifi er, which consists of operational amplifi ers, a programmable operational amplifi er (op-amp) is a key component (Van Helleputte et al., 2008). Programmable op-amps are designed based on the circuit topology in Hogervorst and Huijsing (1996). The op-amps presented in Bronskowski and Schroeder (2007) and Meier auf der Heide et al. (2007) uses this topology for its design and is implemented using 0.35 µm CMOS technology with a supply voltage of 3.3 V. It occupies large area and has large power consumption. So, the supply voltage of programmable op-amps is kept around 1 V to ensure less power dissipation. But, conventional analogue circuit topologies will not work with this supply voltage because as the device sizes are scaled down, the threshold voltage of MOS transistors does not reduce, as this could cause increased leakage currents. This problem can be alleviated by using alternate MOSFETS like fl oating gate MOSFETs, bulk driven MOSFETs and DTMOS. A 1.2 V op-amp has been integrated in a 0.35 µm CMOS process (Riiisanen-Ruotsalainen et al., 2000) using fl oating-gate input transistors to increase the input common mode voltage range of the op-amp, but owing to the capacitive division, the input signal gets attenuated resulting in poor gain, less gain bandwidth product and inferior noise properties. In bulk driven transistors (Lasanen et al., 2000), the threshold voltage limitation disappears but the devices have lower transconductance value because of smaller control capacitance of the depletion layer, larger parasitic capacitance that lowers frequency and higher input referred noise. Op-amp design based on dynamic threshold voltage (DTMOS) transistors is preferred for low voltage, low power bio-medical applications (Achigui et al., 2003). The body and the gate of this DTMOS transistor are biased at the same potential. So, it is capable of processing ultra low-amplitude light signals and is used to build the front-end receiver part of a Near Infrared Spectrore Flectometry (NIRS) device. On the other hand, the op-amp is susceptible to fl icker noise (1/f), which makes it very harmful in low-frequency bio-medical applications because of its power spectrum and voltage offset. So, the programming ability of the op-amp should be exploited to work in both low-noise mode and low-power mode if different medical applications are combined in one chip. An application of this type of Op-amp is used in the analogue front-end of a System on Chip (SoC) for bio-medical signal acquisition (Hafkemeyer et al., 2007). For example, the op-amp is programmed in low-noise mode for sensitive EEG recordings or low-power mode for mobile ECG applications. In contrast to conventional op-amps, programmable op-amps have the advantage of being adaptable to system specifi cation. In this paper, an improved programmable op-amp, which overcomes the disadvantages of conventional op-amps, is proposed and implemented using 130 nm CMOS technology with 1.2 V supply voltage. Section 2 describes the basic operation and design implementation of the existing op-amp architecture. The improved op-amp’s architecture and its design are discussed in Section 3. Simulation results are provided in Section 4 and conclusions are presented in Section 5. |