The design of control systems involving piezoelectric actuators and sensors requires an accurate knowledge of the transfer functions between the inputs and the outputs of the system.
標(biāo)簽： piezoelectric actuators involving accurate
上傳時(shí)間： 2016-05-25
上傳用戶：小寶愛考拉
關(guān)于設(shè)計(jì)piezoelectric transformer inverter 的一篇論文。
標(biāo)簽： piezoelectric transformer inverter 論文
上傳時(shí)間： 2016-07-06
上傳用戶：er1219
Abstract: Quartz crystals are mechanical resonators with piezoelectric properties. The piezoelectricproperties (electric potential across the crystal is proportional to mechanical deformation) allow their use
標(biāo)簽： 晶體振蕩器
上傳時(shí)間： 2013-10-17
上傳用戶：時(shí)代將軍
piezoelectric motors are used in digital cameras for autofocus,zooming and optical image stabilization. Theyare relatively small, lightweight and effi cient, but theyalso require a complicated driving scheme. Traditionally,this challenge has been met with the use ofseparatecircuits, including a step-up converter and an oversizedgeneric full-bridge drive IC. The resulting high componentcount and large board space are especially problematicin the design of cameras for ever shrinking cell phones.The LT®3572 solves these problems by combining astep-up regulator and a dual full-bridge driver in a 4mm× 4mm QFN package. Figure 1 shows a typical LT3572Piezo motor drive circuit. A step-up converter is usedto generate 30V from a low voltage power source suchas a Li-Ion battery or any input power source within thepart’s wide input voltage range of 2.7V to 10V. The highoutput voltage of the step-up converter, adjustable upto 40V, is available for the drivers at the VOUT pin. Thedrivers operate in a full-bridge fashion, where the OUTAand OUTB pins are the same polarity as the PWMA andPWMB pins, respectively, and the OUTA and OUTB pinsare inverted from PWMA and PWMB, respectively. Thestep-up converter and both Piezo drivers have their ownshutdown control. Figure 2 shows a typical layout
上傳時(shí)間： 2013-11-18
上傳用戶：hulee
Semiconductor memory, card readers, microprocessors,disc drives, piezoelectric devices and digitally based systemsfurnish transient loads that a voltage regulator mustservice. Ideally, regulator output is invariant during a loadtransient. In practice, some variation is encountered andbecomes problematic if allowable operating voltage tolerancesare exceeded. This mandates testing the regulatorand its associated support components to verify desiredperformance under transient loading conditions. Variousmethods are employable to generate transient loads, allowingobservation of regulator response
標(biāo)簽： 如何測(cè)試 穩(wěn)壓器 瞬態(tài)響應(yīng) 負(fù)載
上傳時(shí)間： 2013-11-21
上傳用戶：semi1981
In engineering, compensation is planning for side effects or other unintended issues in a design. The design of an invention can itself also be to compensate for some other existing issue or exception. One example is in a voltage-controlled crystal oscillator (VCXO), which is normally affected not only by voltage, but to a lesser extent by temperature. A temperature-compensated version (a TCVCXO) is designed so that heat buildup within the enclosure of a transmitter or other such device will not alter the piezoelectric effect, thereby causing frequency drift. Another example is motion compensation on digital cameras and video cameras, which keep a picture steady and not blurry.
標(biāo)簽： compensation engineering unintended planning
上傳時(shí)間： 2013-12-11
上傳用戶：z754970244
Over many years, RF-MEMS have been a hot topic in research at the technology and device level. In particular, various kinds of mechanical Si-MEMS resonators and piezoelectric BAW (bulk acoustic wave) resonators have been developed. The BAW technology has made its way to commercial products for passive RF filters, in particular for duplexers in RF transceiver front ends for cellular communica- tions. Beyond their use in filters, micromachined resonators can also be used in conjunction with active devices in innovative circuits and architectures.
標(biāo)簽： MEMS-based Circuits Systems and
上傳時(shí)間： 2020-06-06
上傳用戶：shancjb
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