For a variety of reasons, it is desirable to charge batteriesas rapidly as possible. At the same time, overchargingmust be limited to prolong battery life. Such limitation ofovercharging depends on factors such as the choice ofcharge termination technique and the use of multi-rate/multi-stage charging schemes. The majority of batterycharger ICs available today lock the user into one fixedcharging regimen, with at best a limited number ofcustomization options to suit a variety of application needsor battery types. The LTC®1325 addresses these shortcomingsby providing the user with all the functionalblocks needed to implement a simple but highly flexiblebattery charger (see Figure 1) which not only addressesthe issue of charging batteries but also those of batteryconditioning and capacity MONITORing.
上傳時間： 2013-10-19
上傳用戶：royzhangsz
Portable, battery-powered operation of electronic apparatushas become increasingly desirable. Medical, remotedata acquisition, power MONITORing and other applicationsare good candidates for batteryoperation. In some circumstances,due to space, power or reliability considerations,it is preferable to operate the circuitry from a single 1.5Vcell. Unfortunately, a 1.5V supply eliminates almost alllinear ICs as design candidates. In fact, the LM10 opamp-reference and the LT®1017/LT1018 comparators arethe only IC gain blocks fully specifi ed for 1.5V operation.Further complications are presented by the 600mV dropof silicon transistors and diodes. This limitation consumesa substantial portion of available supply range, makingcircuit design diffi cult. Additionally, any circuit designedfor 1.5V operation mustfunction at end-of-life batteryvoltage, typically 1.3V. (See Box Section, “Componentsfor 1.5V Operation.”)
標簽： Circuitry Operation Single Cell
上傳時間： 2013-10-30
上傳用戶：hz07104032
為解決我國水位監測野外條件下長期無人看守的問題，研制開發了基于MSP430單片機的智能水位計。從其組成到各功能分別進行了詳細的介紹，該智能水位計不僅實現了水位數據的實時監測、記錄和定期采集等多種工作模式，而且提高了水位監測精度，實現了水位監測的智能化。 Abstract: In order to solve the problems of long-term unmanned observation in the field water MONITORing，an intelligence water-level meter based on MSP430 is developed composition and every function moduce of the water level meter was introduced in detail. It not only realizes water level data collection and storage， regularly gathering and so on， but also improves the water-level precision ， finally realizes the intelligence.
上傳時間： 2013-11-17
上傳用戶：417313137
便攜式信號采集在機器健康診斷系統中有較高的應用價值。機器健康診斷的信號特點是包括低頻信號。本文研究是為了實現簡易而且低成本的低頻便攜式信號采集。以Microchip公司單片機PIC18F1320為核心設計信號采集電路，實現了信號的采集和保存。系統采用串行電可擦除芯片24LC32A保存數據，經過有線通信，信號數據由串行口通過MAX232芯片輸送到微型計算機接收和保存，最后繪制出信號波形。 微型計算機程序采用Visual Basic編程。研究成功采樣頻率為3 kHz的復雜信號，證明該方案符合設計要求。 Abstract: Portable signal acquisition is useful in machine health MONITORing systems. The signal characteristics of machine health MONITORing includes low frequency signals. The goal of this study is to realize simple, inexpensive and portable low frequency signal sampling. This paper provides the project of signal acquisition system design based on PIC18F1320 microcontroller manufactured by the Microchip Technology Incorporation to achieve signal sampling and storage. The system adopted EEPROM 24LC32A to store the signal data. The microcomputer received data via wired link with the MAX232 IC through the serial port. The microcomputer program, programmed in Visual Basic, received the data, stored it and plotted the signal. The study successfully samples 3kHz complicated signals and thus meets the design requirement.
上傳時間： 2013-11-19
上傳用戶：moerwang
介紹一種基于C8051單片機的動態心電監護系統。該系統由兩部分組成：以C8051F320單片機為核心的數據采集裝置和以PC機為平臺的分析處理系統。硬件電路功耗低，由單片機自帶的USB接口將數據傳送給PC機。軟件平臺采用LabVIEW可視化虛擬儀器系統開發平臺，將傳統儀器的功能模塊集成到計算機中，用戶可通過修改虛擬儀器的程序改變其功能。采用USB接口實時傳輸心電數據，并將數據采集模塊設計為計算機外設，使該系統高速快捷、小巧便攜。 Abstract: In this design，a low-cost ECG electrocardiogram MONITORing system is introduced，which consists of two parts:data acquisition device based on C8051F320and PC terminal as the analysis and processing system.The system is low-power consumption，the data is transmitted to the PC terminal by USB interface of the C8051F320.By using the visible virtual instrument system developing platform LabVIEW，the traditional instruments function modules are integrated into the computer，so the user can modify virtual instrument software to change its function to meet their needs.Using USB in-terface to realize real-time ECG data transmission，in addition，ECG data acquisition module is designed as the computer peripheral，which makes the syetem high-speed and portable.
上傳時間： 2013-11-13
上傳用戶：zhangzhenyu
基于幅移鍵控技術ASK（Amplitude-Shift Keying），以C8051F340單片機作為監測終端控制器，C8051F330D單片機作為探測節點控制器，采用半雙工的通信方式，通過監控終端和探測節點的無線收發電路，實現數據的雙向無線傳輸。收發電路采用直徑為0.8 mm的漆包線自行繞制成圓形空心線圈天線，天線直徑為（3.4±0.3）cm。試驗表明，探測節點與監測終端的通信距離為24 cm，通過橋接方式，節點收發功率為102 mW時，節點間的通信距離可達20 cm。與傳統無線收發模塊相比，該無線收發電路在受體積、功耗、成本限制的場合有廣闊的應用前景。 Abstract: Based on ASK technology and with the C8051F340 and C8051F330D MCU as the controller， using half-duplex communication mode， this paper achieves bi-directional data transfer. Transceiver circuit constituted by enameled wire which diameter is 0.8mm and wound into a diameter （3.4±0.3） cm circular hollow coil antenna. Tests show that the communication distance between detection and MONITORing of the terminal is 24cm，the distance is up to 20cm between two nodes when using the manner of bridging and the node transceiver power is 102mW. Compared with the conventional wireless transceiver modules， the circuit has wide application prospect in small size， low cost and low power consumption and other characteristics.
上傳時間： 2013-10-19
上傳用戶：xz85592677
為了提高環境參數采集的自動化水平，提升效率，設計了無線傳感器系統。本系統運用了傳感器技術、通信技術和單片機技術，實現了對環境溫度、濕度、光照度以及可燃性氣體濃度等參數的檢測。它能夠實時地與上位機進行無線通信，滿足對環境參數實時監測的要求。 Abstract: In order to increase the degree of automation and improve the efficiency of the environment MONITORing parameters，the wireless sensor system was developed.Combining with the technique of sensor,automatic MONITORing，communication and single-chip microcomputer，it realized real-time MONITORing environment parameters,such as temperature，humidity，illumination，concentration of com- bustible gas and so on.At the same time it can communicate with upper personal computers，satisfy the desire of real-time MONITORing.
上傳時間： 2013-11-22
上傳用戶：longlong12345678
為解決輸油管道溫度壓力參數實時監測的問題，設計了以C8051F930單片機作為控制核心的超低功耗輸油管道溫度壓力遠程監測系統。現場儀表使用高精度電橋采集數據，通過433 MHz短距離無線通信網絡與遠程終端RTU進行通信，RTU通過GPRS網絡與PC上位機進行遠程數據傳輸，在上位機中實現數據存儲和圖形化界面顯示，從而實現輸油管道溫度壓力參數的實時監測和異常報警。經實驗證明，該系統的12位數據采集精度滿足設計要求，漏碼率小于1%，正常工作時間超過5個月，能實時有效地監測輸油管道的溫度壓力參數，節省大量人工成本，有效預防管道參數異常造成的經濟損失和環境污染。 Abstract: In order to solve the problems on real-time MONITORing of pipeline temperature and pressure parameters， the ultra-low power remote pipeline temperature and pressure MONITORing system was designed by using the single chip processor C8051F930 as the control core. The high-precision electric bridge was used in field instruments for data collection， the 433MHz short-range wireless communication network was used to make communication between field instrument and RTU， the GPRS was used by the RTU to transmit data to the PC host computer， and the data was stored and displayed in the PC host computer， so the real-time MONITORing and exception alerts of pipeline temperature and pressure parameters were achieved. The experiment proves that the system of which error rate is less than 1% over five months working with the 12-bit data acquisition accuracy can effectively monitor the pipeline temperature and pressure parameters in real time， it saves a lot of labor costs and effectively prevents environmental pollution and economic losses caused by abnormal channel parameters.
上傳時間： 2013-11-07
上傳用戶：cuibaigao
The CAT823, CAT824, and CAT825 provide basic reset and MONITORing functions for the electronic systems. Each device monitors the system voltage and maintains a reset output until that voltage reaches the device’s specified trip value and then maintains the reset output active condition until the device’s internal timer, after a minimum timer of 140ms; toallow the systems power supply to stabilize.
上傳時間： 2014-11-18
上傳用戶：BOBOniu
摘要：本水位監測報警器使用5V低壓直流電源（也可以用3節5號電池代替）就可以對5~15厘米的水位進行監測，用LED顯示和數碼管顯示水位，并可以對不再此范圍內的水位發出報警。主要采用CD4066、74LS86、74LS32、CD4511芯片，再加上數碼管、蜂鳴器、發光二極管、電阻這些器件組成一個簡單而靈敏的監測報警電路，操作簡單，接通電源即可工作。因為大部分電路采用數字電路，所以本水位監測報警器還具有耗能低、準確性高的特點。關鍵字：譯碼電路 報警電路 監測電路 Abstract: The water level alarm MONITORing the use of 5 V low-voltage DC power (can also use three batteries replaced on the 5th) will be able to 5 to 15 centimeters of water level MONITORing, with LED display and digital display of water level, and this can no longer Within the scope of a water level alarm. Mainly CD4066, 74LS86, 74LS32, CD4511 chips, coupled with digital control, buzzer, light-emitting diode, the resistance of these devices composed of a simple and sensitive MONITORing alarm circuits. Because the majority of circuits using digital circuitry, so the water level monitored alarm system also has low energy consumption, high accuracy of the characteristics. Keyword: Decoding circuit alarm circuit MONITORing circuit
上傳時間： 2013-11-05
上傳用戶：王慶才
