電學中的測量技術涉及范圍非常廣,電流測量在電學計量中占有非常重要的位置。如何精確地進行電流測量是精密測量的一大難題。傳統的電流檢測電路多采用運算放大芯片與片外電流檢測電路相結合的方式,電路集成度很低,需要較多的接口和資源才能完成對電路的檢測。本文把所有電路部分都集成在一塊芯片上,包括檢測電阻,運算放大器電路及模擬轉數字轉換電路,從而在電路內部可以進行電流檢測,使電路更好的集成化。前置電路使用二級共源共柵結構的運算放大器,減小溝道長度調制效應造成的電流誤差。10位SAR ADC中采用電容驅動能力強的傳輸門保證了模數轉化器的有效精度。比較器模塊采用再生鎖存器與遲滯比較器作為基礎單元組合解決精密測量的問題。本設計可以作為嵌入芯片內的一小部分而檢測芯片中的微小電流1mA~100mA,工作電壓在1.8v左右,電流檢測精度預期達到10uA的需求。The measurement technology in electricity involves a wide range,and current measurement plays a very important position in electrical measurement.How to accurately measure current is a big problem in precision measurement. The traditional current detecting circuit adopts the combination of the operational amplifier chip and theoff-chip current detecting circuit, The circuit integration is very low, and more interfaces and resources are needed tocomplete the circuit detection.This topic integrates all the circuit parts into one chip, including detection resistance, operational amplifier circuit andanalog to digital conversion circuit. Highly integrated circuit makes the external resources on the chip more intensive,so that current detection can be carried out inside the circuit, so that the circuit can be better integrated. Thefront-end circuit of this project uses two-stage cascade operational amplifier and cascade tube to reduce the currenterror caused by channel length modulation effect. In 10-bit SAR ADC, the transmission gate with strong capacitivedriving ability ensures the effective accuracy of the analog-to-digital converter. Comparator module uses regenerativelatch and hysteresis comparator as basic unit to solve the difficult problem of precision measurement. This topic can beused as a small part of the embedded chip to detect the micro-current in the chip 1 mA~100 mA, the working voltageis about 1.8v, and the current detection accuracy is expected to reach the requirement of 10 uA.
上傳時間： 2022-04-03
上傳用戶：
為設計高效率、低損耗的PFC電路,本文基于UCC28019進行電路設計。以UCC28019輸出的PWM波形來控制Boost升壓斬波為核心電路,使電路中的電容交替地充放電、電感交替的儲存和釋放能量,最后實現在輸入AC20V~24V電壓情況下穩定輸出DC38V。測試結果表明,系統實現效率為95%左右,電壓調整率小于1%,電源功率因數0.99。交流輸入電壓為19.0-25.8 V時,輸出直流電壓穩定性較好,電感無明顯嘯叫且紋波小,具有一定的帶負載能力和實用性。In order to design the PFC circuit with high efficiency and low loss,this paper designs the circuit based on UCC28019.The PWM waveform output by UCC28019 is used to control boost chopper as the core circuit,which alternately charges and discharges capacitors,stores and releases energy by inductors,and finally achieves stable output of DC38 V under the input voltage of AC20 V~24 V.The test results show that the system achieves about 95% efficiency,the voltage adjustment rate is less than 1%,the power factor is 0.99,and the AC input voltage is 19.0-25.8 V.The output DC voltage stability is good,the inductance has no obvious whistle and the ripple is small,so it has certain load capacity and practicability.
上傳時間： 2022-04-03
上傳用戶：
本文首次設計并驗證了基于macom三合一芯片設計的光模塊電路,該電路旨在提供一種滿足SFF-8472中規定的數字診斷功能的低成本SFP+模塊。電路采用激光器驅動、限幅放大器、控制器以及時鐘恢復單元集成的單芯片,在保證高精度數字診斷功能基礎上,實現了低成本高可靠的特點。該電路在光接收接口組件與激光器驅動和限幅放大器單元的限幅放大器部分之間接入濾波器來提高模塊的靈敏度及信號質量。在控制器單元的數字電位器的引腳上采用外加電阻的方式避免出現上電不發光的故障問題。該研究結果為下一代SFP-DD光模塊設計與開發工作,奠定了一定的理論與實踐基礎。This paper designs and validates the optical module circuit based on the MACOM Trinity chip for the first time.This circuit aims to provide a low-cost SFP module which meets the digital diagnosis function specified in SFF-8472.The circuit uses a single chip integrated with laser driver,limiting amplifier,controller and clock recovery unit.On the basis of ensuring high precision digital diagnosis function,it achieves the characteristics of low cost and high reliability.The circuit connects a filter between the optical receiving interface module and the limiting amplifier part of the laser driver and limiting amplifier unit to improve the sensitivity and signal quality of the module.The pin of the digital potentiometer in the controller unit is equipped with an external resistance to avoid the problem of power failure.The research results lay a theoretical and practical foundation for optical module design in high-speed data center.
上傳時間： 2022-04-03
上傳用戶：
Low Power Double Data Rate 3（LPDDR3） JEDEC官方標準共158頁。
上傳時間： 2022-04-12
上傳用戶：
S32K1xx Series Reference Manual 用戶手冊--2029頁 Supports S32K116, S32K118, S32K142, S32K144, S32K146, and S32K148S32K是一款符合AEC-Q100規范、基于32位ARM Cortex-M4F和Cortex-M0+內核的MCU，適用于通用汽車和高可靠性工業應用。The S32K1xx product series further extends the highly scalable portfolio of Arm? Cortex?-M0+/M4F MCUs in the automotive industry. It builds on the legacy of the KEA series, while introducing higher memory options alongside a richer peripheral set extending capability into a variety of automotive applications. With a 2.70–5.5 V supply and focus on automotive environment robustness, the S32K product series devices are well suited to a wide range of applications in electrically harsh environments, and are optimized for cost-sensitive applications offering low pin-count options. The S32K product series offers a broad range of memory, peripherals, and package options. It shares common peripherals and pin counts, allowing developers to migrate easily within an MCU family or among the MCU families to take advantage of more memory or feature integration. This scalability allows developers to use the S32K product series as the standard for their end product platforms, maximizing hardware and software reuse and reducing time to market
標簽： S32K116 S32K118 S32K142 S32K144
上傳時間： 2022-04-16
上傳用戶：jason_vip1
隨著電磁閥在工業和日常應用的增多,其功耗越來越被人們所重視。通過對電磁閥驅動電路的研究,設計一套電磁閥節能驅動電路。不僅提高了電磁閥的響應時間,更重要的是降低了功耗,使電磁閥由工作在大電流狀態下,變成大電流啟動小電流維持的工作狀態。減少了由電流過大引起的電磁閥線圈過熱,增加了電磁閥的安全性。The power consumption of an electromagnetic valve is drawing increasingly more attentiori as it is widely used in industrial production and daily life. In this study, an energy - saving driving circuit of electromagnetic valves was designed. It can make an electromagnetic valve to start with a high current while work with a low current; thereby the power consumption can be reduced. Besides, it can shorten the response time of an electromagnetic valve and improve the security of the valve.
上傳時間： 2022-04-16
上傳用戶：
為了提高超高頻RFID系統中閱讀器在低信噪比的情況下仍具有較高的識別能力,提出一種基于FPGA系統結合軟件無線電方法實現超高頻RFID射頻前端電路方案。超高頻射頻識別系統必須符合EPC Class 1generation 2標準,所設計的電路系統以Xilinx公司的XC6SLX16-2CSG324FPGA芯片為硬件基礎,將數字基帶調制解調和中頻濾波電路在FPGA系統中設計實現,重點闡述了射頻前端電路的設計結構、AD/DA轉換電路,以及數字濾波器的設計。實驗結果表明,所設計的超高頻RFID閱讀器簡化了前端電路系統結構,提升了穩定性,增強了抗干擾能力。該電路系統在信噪比較低的情況下,能夠較好地實現915MHz頻率的射頻接收和發送。In order to improve the reader UHF RFID system still has a higher ability to identify,in the case of low signal-to-noise ratio.The UHF RFID systems must comply with EPC Class 1 generation 2 standard.In this paper,the design of the circuit system based on Xilinx＇s XC6SLX16-2CSG324 FPGA chip,and presents UHF RFID RF front-end circuit with software radio based on FPGA system.Digital baseband modem and IF filter circuit is designed and implemented in the FPGA system,and focused on designing the structure of the RF front-end circuit,AD/DA conversion circuits,and digital filter.Experimental results show that the UHF RFID reader de...
標簽： 915mhz 超高頻 rfid 閱讀 射頻 前端 電路 設計
上傳時間： 2022-04-17
上傳用戶：shjgzh
超聲波換能器作為一種實用的檢測手段，能實現聲波所攜帶的信息和電能之間轉換。它的性能優良，價格低廉，操作方便，易于調試，因此在工農業生產中發揮著重要的作用。但目前換能器驅動電路的發射頻率多為40 kHz，本文針對1 MHz的超聲波換能器電路進行了設計，主要介紹了它的發射驅動電路和接收驅動電路的設計方案，并對它們的功能進行了詳細地說明。最后搭建實驗平臺，并對電路的輸入、輸出模塊進行了測試。實驗結果表明，換能器電路運行良好，可以為超聲波高精度測量領域的應用提供參考。As a practical means of detection, ultrasonic transducer can realize the conversion between theinformation carried by sound wave and electric energy.It has the advantages of excellent performance,low cost, convenient operation and debugging, so plays an important role in industrial and agriculturalproduction.However, the transmitting frequency of the driving circuit for most transducer is 40 kHz.Thecircuit of 1 MHz ultrasonic transducer is designed In this paper. It mainly introduces the emissive drivingcircuit and the receiving circuit design and the detailed function of them. Finally, the experimentalplatform is built, and the circuit of input and output were tested. Experiments show that the transducer＇ s...
上傳時間： 2022-04-28
上傳用戶：
The JW? 7805 is a low noise low-dropout (LDO) voltage regulator with enable function that operates from 1.8V to 5.5V. It provides up to 300mA of output current and offers low-power operation in miniaturized packaging. JW7805 supports fixed output voltage 0.9V, 1.0V, 1.05V, 1.1V,1.2V, 1.3V, 1.35V, 1.5V, 1.8V, 1.85V, 2.1V, 2.2V, 2.3V, 2.5V, 2.6V, 2.7V, 2.8V, 2.85V, 2.9V, 3.0V,3.1V, 3.3V, 3.6V, 4.2V, 4.4V and 5.0V. The features of low quiescent current as low as 6uA and almost zero disable current are ideal for powering the battery equipment. JW7805’s low output noise and high PSRR are also friendly to RF systems.
標簽： JW7805
上傳時間： 2022-05-06
上傳用戶：slq1234567890
基于TMS320F28335的超聲波流量計硬件原理圖+軟件源碼本文以TMS320F28335 處理器為核心，設計一種用于管道流量測量的超聲波流量計。系統硬件由核心板，超聲波發射和接收電路，切換電路，超聲換能器，基于ADS805 的高速信號采集電路，人機交互以及電源等模塊構成。采用時差法進行管道流量測量，時差測量采用SCOT 加權的廣義互相關時延估計算法。本論文設計的超聲波流量計具有測量速度快、準確性好、成本低等優點。關鍵字：C2000，超聲波，流量，廣義互相關算法AbstractA kind of ultrasonic flowmeter using for the pipe flow measurement is designed based onTMS320F28335 in this paper. The system hardware consists of the following parts: the core board,ultrasonic signal transmitter and receiver circuits, switch circuit, ultrasonic transducer, signalacquisition circuit based on ADS805, human-computer interaction module and power supplymodule, etc. The system use the method of time difference for pipeline flow measurement and thetime difference is calculated by the time-delay algorithm of SCOT weighted generalizedcross-correlation. The ultrasonic flowmeter has the features of high testing speed, high precisionand low cost, etc.Keywords: C2000,Ultrasonic, Flow, Generalized Cross-Correlation Algorithm
標簽： tms320f28335 超聲波流量計
上傳時間： 2022-05-06
上傳用戶：
