Abstract: Quartz crystals are mechanical resonators with piezoelectric properties. The piezoelectricproperties (electric potential across the crystal is proportional to mechanical deformation) allow their use
Abstract: mechanical misalignment and scaling factors lead to a mismatch between the values coming from a touchscreen panel (as translated by a touch screen controller) and the display (typically an LCD) on which the touch screenpanel is mounted. This tutorial discusses how to calibrate the touch screen panel to match the display.
Abstract: A laser module designer can use a fixed resistor, mechanical pot, digital pot, or a digital-to-analogconverter (DAC) to control the laser driver's modulation and bias currents. The advantages of a programmablemethod (POT or DAC) are that the manufacturing process can be automated and digital control can be applied(e.g., to compensate for temperature). Using POTs can be a more simple approach than a DAC. There can be aslight cost advantage to using a POT, but this is usually not significant relative to other pieces of the design.Using a DAC can offer advantages, including improved linearity (translating to ease of software implementationand ability to hit the required accuracy), increased board density, a wider range of resolutions, a betteroptimization range, ease of use with a negative voltage laser driver, and unit-to-unit consistency
This product integration guide provides application circuit information for theSmartMesh® LTP5903PC wireless embedded network manager. This guide is acompanion to the 020-0039 SmartMesh LTP5903PC Datasheet, whichdescribes overall product behavior, including detailed information about normaloperating conditions, electrical and mechanical specifications, hardware andsoftware interfaces, and connector pinouts.
Abstract: A resistive feedback network is often used to set the output voltage of a power supply. A mechanical potentiometer (pot)conveniently solves the problem of adjusting a power supply. For easier automatic calibration, a mechanical pot can be replaced witha digital pot. This application note presents a calibration solution that uses a digital pot, because digipots are smaller, do not movewith age or vibration, and can be recalibrated remotely. This proposed solution reduces the susceptibility of the system to thetolerance of the digital pot's end-to-end resistance, making the solution optimal fordesigners. This application note also explainssome of the equations required to calculate the resistor chain values and to use a digital pot in this way. A spreadsheet withstandard reisistor values is available for easy calculations.
PCI ExpressTM is the third generation of PCI (PeripheralComponent Interconnect) technology used to connect I/Operhipheral devices in computer systems. It is intended asa general purpose I/O device interconnect that meets theneeds of a wide variety of computing platforms such asdesktop, mobile, server and communications. It alsospecifies the electrical and mechanical attributes of thebackplane, connectors and removable cards in thesesystems.
Abstract: As electronic systems take over many of the mechanical functions in a car—ranging from engine timing to steering andbraking—there is a growing concern about fault tolerance. There should not be a single point of failure that would prevent a car fromat least "limping" off the road or making it to the nearest service station. Redundant systems, watchdog timers, and other controlcircuits are used to reroute signals and perform other functions that ensure that a vehicle can safely make it off the road when afailure occurs.
為了提高PCB板制作的效率，改變傳統(tǒng)的化學(xué)腐蝕制板工藝，使用機(jī)械仿形銑制作電路板的方法，設(shè)計(jì)了以ATMEGA16單片機(jī)為核心部件的PCB板雕刻機(jī)控制系統(tǒng)。其中包括PCB雕刻機(jī)的基本功能、主要硬件電路設(shè)計(jì)和軟件的實(shí)現(xiàn)流程，并給出了相關(guān)設(shè)計(jì)電路。重點(diǎn)分析了雕刻機(jī)步進(jìn)電機(jī)的驅(qū)動電路以及主軸電機(jī)的驅(qū)動電路，該雕刻機(jī)經(jīng)實(shí)際運(yùn)行，系統(tǒng)工作良好，可有效提高PCB板的制作效率。
Abstract:
In order to improve the efficiency of production of PCB board and change the traditional chemical etching plates， using of mechanical copying milling method makes circuit boards，this paper introduces the PCB engraving machine control system used ATMEGA16 microcomputer as the core components. It includes basic function， the hardware circuit design and software realization process， and gives the corresponding circuit design.It analyses the drive circuit of engrawing machine stepper motor and spindle motor in detail. This engraving machine by practical operation， the system works well， which can effectively improve the production efficiency of PCB board.
針對目前使用的RS232接口數(shù)字化B超鍵盤存在PC主機(jī)啟動時不能設(shè)置BIOS，提出一種PS2鍵盤的設(shè)計(jì)方法。基于W78E052D單片機(jī)，采用8通道串行A/D轉(zhuǎn)換器設(shè)計(jì)了8個TGC電位器信息采集電路，電位器位置信息以鍵盤掃描碼序列形式發(fā)送，正交編碼器信號通過XC9536XL轉(zhuǎn)換為單片機(jī)可接收的中斷信號，軟件接收到中斷信息后等效處理成按鍵。結(jié)果表明，在滿足開機(jī)可設(shè)置BIOS同時，又可實(shí)現(xiàn)超聲特有功能，不需要專門設(shè)計(jì)驅(qū)動程序，接口簡單，成本低。
Abstract: Aiming at the problem of the digital ultrasonic diagnostic imaging system keyboard with RS232 interface currently used couldn?蒺t set the BIOS when the PC boot， this paper proposed a design method of PS2 keyboards. Based on W78E052D microcontroller，designed eight TGC potentiometers information acquisition circuit with 8-channel serial A/D converter， potentiometer position information sent out with keyboard scan code sequentially.The control circuit based on XC9536 CPLD is used for converting the mechanical actions of the encoders into the signals that can be identified by the MCU， software received interrupt information and equivalently treatmented as key. The results show that the BIOS can be set to meet the boot， ultrasound specific functionality can be achieved at the same time， it does not require specially designed driver，the interface is simple and low cost.
