Abstract: The DS1875 features a Pulse-width modulation (PWM) controller that can be used to control aDC-DC converter. The DC-DC converter can then be used to generate the high bias voltages necessaryfor avalanche photodiodes (APDs). This application note describes the operation of a boost converterthat uses the DS1875. Discussion covers the selection of the inductor and switching frequency, and theselection of components that improve the efficiency of the converter. Test data are presented.
上傳時間: 2013-10-26
上傳用戶:lyson
The LTC®3562 quad output step-down regulator is designedfor multicore handheld microprocessor applications thatoperate from a single Li-Ion battery. Its four monolithic, higheffi ciency buck regulators support Intel’s mobile CPU P-Stateand C-State energy saving operating modes. The outputvoltages are independently controllable via I2C, and eachoutput can be independently started and shut down. Designerscan choose from power saving Pulse-skipping mode orBurst Mode® operation, or select low noise LDO mode. Thespace-saving LTC3562 is available in a 3mm × 3mm QFNpackage and requires few external components.
上傳時間: 2013-10-07
上傳用戶:1583060504
數字控制的交流調速系統所選用的微處理器、功率器件及產生PWM波的方法是影響交流調速系統性能好壞的直接因素。在介紹了正弦脈寬調制(SPWM)技術的基礎上,設計了一種以8098單片機作為控制器,以智能功率模塊IPM為開關器件的變頻調速系統。通過軟件編程,產生正弦脈沖寬度調制波形來控制絕緣柵雙極晶體管的導通和關斷,從而達到控制異步電動機轉速的目的。實驗結果表明,該系統可調頻率調電壓,穩定度高,調速范圍寬,具有較強的實用價值 Abstract: AC variable speed with digital control systems used microprocessors, power devices and generate PWM wave is the direct factors of affecting the performance AC speed regulation system. On the basis of introducing the sinusoidal Pulse width modulation (SPWM) technology,this paper designed variable speed system which used 8098 as a controller, intelligent power module IPM as switching device. Through software programming, resulting in sinusoidal Pulse width modulation waveform to control the insulated gate bipolar transistor turn on and off, so as to achieve the purpose of speed control of induction motors. Experimental results show that the system can adjust frequency modulation voltage, high stability, wide speed range, has a strong practical value.
上傳時間: 2013-11-14
上傳用戶:ynwbosss
針對目前燃氣灶市場的狀況,提出一種基于PIC16C711單片機的燃氣灶脈沖點火控制器設計,具體包括有系統的組成和功能介紹、硬件電路設計及軟件功能實現。 Abstract: Aiming at today’s gas cooker market, a Pulse ignition controler design based on PIC16C711 is presented.The specific descriptions of system components and functions,hardware circuit design and software function are given.
上傳時間: 2013-10-31
上傳用戶:zhqzal1014
針對材料試驗機等設備中要求測量或控制材料拉伸或壓縮的位移,一般采用光電軸角編碼器檢測位置信號,輸出正交編碼脈沖信號。若采用其他方法檢測位置信號,必然導致電路設計復雜,可靠性降低。因此,提出一種基于LS7266R1的電子式萬能材料試驗機設計方案。給出了試驗機中的控制器工作原理,LS7266R1與單片機的接口硬件設計,以及主程序軟件流程圖。巧妙地把力量傳感器,位移傳感器等機械運動狀態的壓力或拉力以及位置坐標,變成了電壓信號和電脈沖數字信號,供A/D測量和LS7266R1計數,從而實現了獨立完成材料試驗控制或通過PC機串口命令完成材料試驗控制。 Abstract: Aiming at the requirement that the displacement of the tension and compression always be tested and controlled in the equipement such as material testing machine. The position signal was tested by photoelectric axial angle coder. Therefore, the paper proposes the design of electronic universal testing machine design based on LS7266R1. If the position signal detected by other methods, will inevitably lead to the circuit design complexity, reliability decreased. The work theory of the controller, the hardware interface design between LS7266R1 and single chip, and the flow chart of main program, are presented in this paper. The signal of the compression or tension power and displacement at working, which tested by power sensor and displacement sensor especially, is changed into electric voltage and electric Pulse numerical signals. And these signals can be tested by A/D and counted by LS7266R1. Finally the test of the material properties can be controlled by itself, or controlled by the COM command of PC.
上傳時間: 2013-11-02
上傳用戶:yl1140vista
HT6221發碼的接收原理及應用 HT6221 是Holtek 公司生產的多功能編碼芯片,采用PPM(Pulse Position Modulation)進行編碼
上傳時間: 2014-09-10
上傳用戶:AbuGe
This application report discusses the design of non-invasive optical plethysmographyalso called as pulsoximeter using the MSP430FG437 Microcontroller (MCU). Thepulsoximeter consists of a peripheral probe combined with the MCU displaying theoxygen saturation and Pulse rate on a LCD glass. The same sensor is used for bothheart-rate detection and pulsoximetering in this application. The probe is placed on aperipheral point of the body such as a finger tip, ear lobe or the nose. The probeincludes two light emitting diodes (LEDs), one in the visible red spectrum (660nm) andthe other in the infrared spectrum (940nm). The percentage of oxygen in the body isworked by measuring the intensity from each frequency of light after it transmitsthrough the body and then calculating the ratio between these two intensities.
標簽: Pulsoximeter Single-Chip Des
上傳時間: 2013-10-27
上傳用戶:黑漆漆
基于PIC單片機的脈沖電源:設計了一種金屬凝固過程用脈沖電源。該電源采用PIC16F877作為主控芯片,實現對窄脈沖電流幅值的檢測,以及時電流脈沖幅值根據模糊PID算法進行閑環控制。使用結果表明:該電源的輸出脈沖波形良好,電流幅值穩定,滿足合金材料凝固過程的工藝要求且運行穩定可靠。關鍵詞:脈沖電源;PIC16F877單片機;模糊PID;閑環控制 Abstract:A kind of Pulse power supply was designed which uses in the metal solidification process ..I11is power supply used PIC16F877 to take the master control chip reali on to the narrow Pulse electric current peak-to-peak value examination,carried on the closed-loop control to the electric current Pulse peak-to-peak value basis fuzzy PID algorithm.The use result indicated ,this power supply output se profile is good,and the electric current peak-to-p~k value is stable,It satisfies the alloy material solidification process the technological requirement and movement stable reliable,Key words:p se po wer supply;PIC16F877single-chip microcontroller;f r PID;closed-loop control
上傳時間: 2013-10-27
上傳用戶:xcy122677
利用TPM2定時器產生一通道語音信號輸出,語音數據為PCM格式:PCM的概念脈沖編碼調制(Pulse Code Modulation,PCM)是概念上最簡單、理論上最完善的編碼系統,是最早研制成功、使用最為廣泛的編碼系統,但也是數據量最大的編碼系統。PCM的編碼原理比較直觀和簡單,它的原理框圖如圖1-1所示。在這個編碼框圖中,它的輸入是模擬聲音信號,它的輸出是PCM樣本。圖中的“防失真濾波器”是一個低通濾波器,用來濾除聲音頻帶以外的信號;“波形編碼器”可暫時理解為“采樣器”,“量化器”可理解為“量化階大小(step-size)”生成器或者稱為“量化間隔”生成器。
上傳時間: 2013-11-21
上傳用戶:DXM35
基于單片機的步進電機開環控制系統:通過ATMEL89C51單片機對步進電機進行控制,主要介紹了步進電機控制器、驅動電路和LED顯示電路的設計,實現了步進電機的開環控制。在步進電機控制器的設計中,重點闡述了脈沖產生電路以及對速度的控制。該系統具有成本低、控制方便的特點。關鍵詞: 單片機; 步進電機; 開環控制 Abstract: The design using ATMEL89C51 single chip to control the step2motor with its controller, driving circuit and LED disp lay circuit to realize step motor open2loop controlwere introduced. For the controller in this design,the circuit to p roduce Pulse and the speed controlwere expatiated emphatically. This system possesses features of lower cost, easier control.Key words: single ch ip; step2motor; open2loop con trol
上傳時間: 2013-10-13
上傳用戶:cicizoe