Single-amplifier integrator-based low power CMOS filter for video frequency applications

“This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder." “Copyright IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.”This paper describes a new low power fully differential second-order continuous-time low pass filter for use at video frequencies. The filter uses a single active device in combination with MOSFET resistors and grounded capacitors to achieve very low power consumption, small chip area and large dynamic range. The ideal integrator is realised using an internally compensated opamp consisting of only current mirrors and voltage buffers, whilst the lossy integrator is implemented by a single passive RC circuit. The filter has been simulated using a CMOS process. Results show that with a single 5 V power supply, cut-off frequency can be tuned from 3.5 MHz to 8 MHz, dynamic range is better than 67 dB, and power consumption is less than 1.7 mW

High frequency and high dynamic range continuous time filters

Many modern communication systems use orthogonal frequency division multiplexing (OFDM) and discrete multi-tone (DMT) as modulation schemes where high data rates are transmitted over a wide frequency band in multiple orthogonal subcarriers. Due to the many advantages, such as flexibility, good noise immunity and the ability to be optimized for medium conditions, the use of DMT and OFDM can be found in digital video broadcasting, local area wireless network (IEEE 802.11a), asymmetric digital subscriber line (ADSL), very high bit rate DSL (VDSL) and power line communications (PLC). However, a major challenge is the design of the analog frontend; for these systems a large dynamic range is required due to the significant peak to average ratio of the resulting signals. In receivers, very demanding high-performance analog filters are typically used to block interferers and provide anti-aliasing before the subsequent analog to digital conversion stage. For frequencies higher than 10MHz, Gm-C filter implementations are generally preferred due to the more efficient operation of wide-band operational transconductance amplifiers (OTA). Nevertheless, the inherent low-linearity of open-loop operated OTA limits the dynamic range. In this dissertation, three different proposed OTA linearity enhancement techniques for the design of high frequency and high dynamic range are presented. The techniques are applied to two filter implementations: a 20MHz second order tunable filter and a 30MHz fifth order elliptical low-pass filter. Simulation and experimental results show a spurious free dynamic range (SFDR) of 65dB with a power consumption of 85mW. In a figure of merit where SFDR is normalized to the power consumption, this filter is 6dB above the trend-line of recently reported continuous time filters

Real-time extraction of growth rates from rotating substrates during molecular-beam epitaxy

We present a method for measuring molecular‐beam epitaxy growth rates in near real‐time on rotating substrates. This is done by digitizing a video image of the reflection high‐energy electron diffraction screen, automatically tracking and measuring the specular spot width, and using numerical techniques to filter the resulting signal. The digitization and image and signal processing take approximately 0.4 s to accomplish, so this technique offers the molecular‐beam epitaxy grower the ability to actively adjust growth times in order to deposit a desired layer thickness. The measurement has a demonstrated precision of approximately 2%, which is sufficient to allow active control of epilayer thickness by counting monolayers as they are deposited. When postgrowth techniques, such as frequency domain analysis, are also used, the reflection high‐energy electron diffraction measurement of layer thickness on rotating substrates improves to a precision of better than 1%. Since all of the components in the system described are commercially available, duplication is straightforward

Persepsi pelajar sarjana muda kejuruteraan elektrik terhadap program latihan industri, Kolej Universiti Teknologi Tun Hussein Onn

Kajian ini dijalankan bertujuan untuk mengetahui persepsi Pelajar Sarjana Muda Kejuruteraan Elektrik Terhadap Program Latihan Industri, KUiTTHO berdasarkan kepada 4 faktor iaitu kesesuaian penempatan program latihan industri, kesesuaian pendedahan pelajaran teori di KUiTTHO dan amali di tempat program latihan industri, tahap kerjasama yang diberikan oleh pihak industri kepada pelajar d a n kesediaan pelajar melakukan kerja yang diberi semasa program latihan industri. Sampel kajian adalah terdiri daripada pelajar-pelajar Sarjana Mud a Kejuruteraan Elektrik di KUITTHO yang telah menjalani program latihan industri. Set soal selidik terdiri daripada 3 bahagian iaitu bahagian A yang bertujuan untuk mendapatkan maklumat diri responden manakala bahagian Bertujuan untuk mengetahui kesesuaian program latihan industri yang telah diikuti oleh pelajar dan bahagian C adalah cadangan untuk meningkatkan mutu program latihan industri. Data - data yang diperolehi dianalisis menggunakan perisisan SPSS 10.0 for Windows (Statistical Package for the Social Science version 10) dan dipersembahkan dalam bentuk peratusan, carta dan keterangan analisis. Dapatan kajian secara umumnya menunjukkan reaksi positif dimana bagi semua aspek menunjukkan min keseluruhan yang tingg

Frequency-modulated continuous-wave LiDAR compressive depth-mapping

We present an inexpensive architecture for converting a frequency-modulated continuous-wave LiDAR system into a compressive-sensing based depth-mapping camera. Instead of raster scanning to obtain depth-maps, compressive sensing is used to significantly reduce the number of measurements. Ideally, our approach requires two difference detectors. % but can operate with only one at the cost of doubling the number of measurments. Due to the large flux entering the detectors, the signal amplification from heterodyne detection, and the effects of background subtraction from compressive sensing, the system can obtain higher signal-to-noise ratios over detector-array based schemes while scanning a scene faster than is possible through raster-scanning. %Moreover, we show how a single total-variation minimization and two fast least-squares minimizations, instead of a single complex nonlinear minimization, can efficiently recover high-resolution depth-maps with minimal computational overhead. Moreover, by efficiently storing only $2m$ data points from $m<n$ measurements of an $n$ pixel scene, we can easily extract depths by solving only two linear equations with efficient convex-optimization methods

A 0.18µm CMOS DDCCII for Portable LV-LP Filters

In this paper a current mode very low voltage (LV) (1V) and low power (LP) (21 µW) differential difference second generation current conveyor (CCII) is presented. The circuit is developed by applying the current sensing technique to a fully balanced version of a differential difference amplifier (DDA) so to design a suitable LV LP integrated version of the so-called differential difference CCII (DDCCII). Post-layout results, using a 0.18µm SMIC CMOS technology, have shown good general circuit performances making the proposed circuit suitable for fully integration in battery portable systems as, for examples, fully differential Sallen-Key bandpass filter

Real-World Repetition Estimation by Div, Grad and Curl

We consider the problem of estimating repetition in video, such as performing push-ups, cutting a melon or playing violin. Existing work shows good results under the assumption of static and stationary periodicity. As realistic video is rarely perfectly static and stationary, the often preferred Fourier-based measurements is inapt. Instead, we adopt the wavelet transform to better handle non-static and non-stationary video dynamics. From the flow field and its differentials, we derive three fundamental motion types and three motion continuities of intrinsic periodicity in 3D. On top of this, the 2D perception of 3D periodicity considers two extreme viewpoints. What follows are 18 fundamental cases of recurrent perception in 2D. In practice, to deal with the variety of repetitive appearance, our theory implies measuring time-varying flow and its differentials (gradient, divergence and curl) over segmented foreground motion. For experiments, we introduce the new QUVA Repetition dataset, reflecting reality by including non-static and non-stationary videos. On the task of counting repetitions in video, we obtain favorable results compared to a deep learning alternative