A Survey on Analog-to-Digital Converter Integrated Circuits for Miniaturized High Resolution Ultrasonic Imaging System

As traditional ultrasonic imaging systems (UIS) are expensive, bulky, and power-consuming, miniaturized and portable UIS have been developed and widely utilized in the biomedical field. The performance of integrated circuits (ICs) in portable UIS obviously affects the effectiveness and quality of ultrasonic imaging. In the ICs for UIS, the analog-to-digital converter (ADC) is used to complete the conversion of the analog echo signal received by the analog front end into digital for further processing by a digital signal processing (DSP) or microcontroller unit (MCU). The accuracy and speed of the ADC determine the precision and efficiency of UIS. Therefore, it is necessary to systematically review and summarize the characteristics of different types of ADCs for UIS, which can provide valuable guidance to design and fabricate high-performance ADC for miniaturized high resolution UIS. In this paper, the architecture and performance of ADC for UIS, including successive approximation register (SAR) ADC, sigma-delta (Σ-∆) ADC, pipelined ADC, and hybrid ADC, have been systematically introduced. In addition, comparisons and discussions of different types of ADCs are presented. Finally, this paper is summarized, and presents the challenges and prospects of ADC ICs for miniaturized high resolution UIS.

Multiplikasi Input Analog pada PLC menggunakan Multiplekser IC74HC4067

ABSTRAKKebutuhan sistem otomasi untuk pekerjaan tentu sangat dituntut untuk menjadi lebih efektif dan efisien seperti halnya pemanfaatan PLC dalam bidang industri untuk menjalankan segala aktifitas menjadi otomatis, terkadang sistem ADC (analog to digital converter) pada PLC itu terbatas, dan harus diberi tambahan ekstensi eksternal yang dijual terpisah di masing-masing vendor. Tentunya harganya juga terkadang lebih mahal dari pada Unit pemrosesnya, hal ini yang sering menjadi sebuah pertimbangan. Contoh nya sistem ADC pada PLC CP1L-E memiliki 2 kanal. Oleh karena itu penelitian ini dilakukan, dengan melakukan perancangan multiplekser dan demultiplekser analog dengan memanfaatkan IC 74HC4067, hasil dari penelitian ini dalam 1 kanal input analog PLC CP1L-E dapat menjadi 16 kanal input dengan waktu pensaklaran direkomendasikan diatas 0,1detik / kanal berdasarkan hasil selisih pembacaan nilai ADC dibandingkan dengan tanpa melalui multiplekser berkisar antara 0,00% sampai 1,969%, dan multiplekser ini direkomendasikan untuk penggunaan sinyal input pada tegangan0 sampai 5 volt.Kata kunci: ADC, Multiplekser,Demultiplekser, IC CD74HC4067, PLC ABSTRACTThe need for automation systems for work is certainly highly demanded to be more effective and efficient as well as the use of PLCs in the industrial sector to carry out all activities automatically, sometimes the ADC (analog to digital converter) system on the PLC is limited, and must be given additional external extensions that are sold separately for each vendor. Of course the price is also sometimes more expensive than the processing unit, this is often a consideration. For example, the ADC system on the CP1L-E PLC has 2 channels. Therefore, this research was carried out, by designing an analog multiplexer and demultiplexer using IC 74HC4067, the results of this study in 1 analog input channel PLC CP1L-E can be 16 input channels with recommended switching times above 0.1 seconds / channel based on the results of the difference. The reading of the ADC value compared to without going through the multiplexer ranges from 0.00% to 1.969%, and this multiplexer is recommended for the use of input signals at a voltage of 0 to 5 volts.Keywords: ADC, Multiplexer, Demultiplexer, IC CD74HC4067, PLC

Equipment for measuring the characteristics of X-ray

X-ray measurement equipment is designed which utilizes a pair of photodiode detectors. The equipment is designed which utilizes a pair of photodiode detectors units which receive X-rays through filters with different attenuation coefficients for X-rays. The photodiode detector units preferably includes two pairs of photodiode detectors arranged symmetrically in four quadrants with the diodes in each detector unit in diagonally opposite quadrants. The outputs of the detector units are passed to variable gain amplifiers, gains of which are adjusted to bring the output voltages within a desired range, and the outputs of the amplifiers are integrated by integrators. After a selected period of time, the integration is stopped and the output voltages of the integrators are held and transmitted to an analog-to-digital converter. The ratio of the two output signals from a pair of photodiode detectors represents the kVp value of the X-ray machine and another pair of photodiode detectors used to measure the relative current in milliamps (mA) and exposure time of the x-ray unit.In this study, the equipment have been made for measuring the characteristics of X-Ray with an accuracy of kVp (kV), I (mA) is 5% and the 2% T.