Sensors for pressure, load, temperature, acceleration andmany other physical quantities often take the form of aWheatstone bridge. These sensors can be extremely linearand stable over time and temperature. However, mostthings in nature are only linear if you don’t bend them toomuch. In the case of a load cell, Hooke’s law states that thestrain in a material is proportional to the applied stress—as long as the stress is nowhere near the material’s yieldpoint (the “point of no return” where the material ispermanently deformed).
上传时间: 2013-11-13
上传用户:墙角有棵树
LAYOUT REPORT .............. 1 目錄.................. 1 1. PCB LAYOUT 術語解釋(TERMS)......... 2 2. Test Point : ATE 測試點供工廠ICT 測試治具使用............ 2 3. 基準點 (光學點) -for SMD:........... 4 4. 標記 (LABEL ING)......... 5 5. VIA HOLE PAD................. 5 6. PCB Layer 排列方式...... 5 7.零件佈置注意事項 (PLACEMENT NOTES)............... 5 8. PCB LAYOUT 設計............ 6 9. Transmission Line ( 傳輸線 )..... 8 10.General Guidelines – 跨Plane.. 8 11. General Guidelines – 繞線....... 9 12. General Guidelines – Damping Resistor. 10 13. General Guidelines - RJ45 to Transformer................. 10 14. Clock Routing Guideline........... 12 15. OSC & CRYSTAL Guideline........... 12 16. CPU
上传时间: 2013-12-20
上传用户:康郎
Integrated EMI/Thermal Design forSwitching Power SuppliesWei ZhangThesis submitted to the Faculty of theVirginia Polytechnic Institute and State Universityin partial fulfillment of the requirements for the degree of Integrated EMI/Thermal Design forSwitching Power SuppliesWei Zhang(ABSTRACT)This work presents the modeling and analysis of EMI and thermal performancefor switch power supply by using the CAD tools. The methodology and design guidelinesare developed.By using a boost PFC circuit as an example, an equivalent circuit model is builtfor EMI noise prediction and analysis. The parasitic elements of circuit layout andcomponents are extracted analytically or by using CAD tools. Based on the model, circuitlayout and magnetic component design are modified to minimize circuit EMI. EMI filtercan be designed at an early stage without prototype implementation.In the second part, thermal analyses are conducted for the circuit by using thesoftware Flotherm, which includes the mechanism of conduction, convection andradiation. Thermal models are built for the components. Thermal performance of thecircuit and the temperature profile of components are predicted. Improved thermalmanagement and winding arrangement are investigated to reduce temperature.In the third part, several circuit layouts and inductor design examples are checkedfrom both the EMI and thermal point of view. Insightful information is obtained.
上传时间: 2013-11-10
上传用户:1595690
精确度0.05%满刻度±1位数(Accuracy 0.05%F.S.±1digit) 可测量交直流电流/交直流电压/电位计/传送器/Pt-100/荷重元/电阻等信号(Measuring DCA/DCV/ACA/ACV/Potentiometer/Transmitter/Pt-100/Load Cell/Resistor/etc……) 显示范围0-19999可任意规划(Programmable rate 0 to 1999 digit) 小数点可任意规划(Decimal point can be modified) 尺寸小,稳定性高(Dimension small & High stability)
上传时间: 2014-01-25
上传用户:RQB123
The LTC®3414 offers a compact and efficient voltage regulatorsolution for point of load conversion in electronicsystems that require low output voltages (down to 0.8V)from a 2.5V to 5V power bus. Internal power MOSFETswitches, with only 67mW on-resistance, allow theLTC3414 to deliver up to 4A of output current with efficiencyas high as 94%. The LTC3414 saves space by operatingwith switching frequencies as high as 4MHz, enabling theuse of tiny inductors and capacitors.
上传时间: 2014-01-03
上传用户:dongbaobao
Multiple-voltage electronics systems often requirecomplex supply voltage tracking or sequencing, whichif not met, can result in system faults or even permanentfailures in the fi eld. The design diffi culties in meetingthese requirements are often compounded in distributedpowerarchitectures where point-of-load (POL) DC/DCconverters or linear regulators are scattered across PCboard space, sometimes on different board planes. Theproblem is that power supply circuitry is often the lastcircuitry to be designed into the board, and it must beshoehorned into whatever little board real estate is left.Often, a simple, drop-in, fl exible solution is needed tomeet these requirements.
上传时间: 2013-10-08
上传用户:15071087253
Easy-to-use and compact point-of-load power suppliesare necessary in systems with widely distributed, highcurrent, low voltage loads. The LTC®3415 provides acompact, simple and versatile solution. It includes a pairof integrated complementary power MOSFETs (32mΩtop and 25mΩ bottom) and requires no external senseresistor. A complete design requires an inductor andinput/output capacitors, and that’s it. The result is a fast,constant frequency, 7A current mode DC/DC switchingregulator.
上传时间: 2013-10-18
上传用户:avensy
Advancements in board assembly, PCB layout anddigital IC integration have produced a new generationof densely populated, high performance systems. Theboard-mounted point-of-load (POL) DC/DC power suppliesin these systems are subject to the same demandingsize, high power and performance requirements asother subsystems. The rigorous new POL demands aredifficult to meet with traditional controller or regulatorICs, or power modules.
上传时间: 2014-12-24
上传用户:lbbyxmraon
Many telecommunications and computing applicationsneed high effi ciency step-down DC/DC converters thatcan operate from a very low input voltage. The highoutput power synchronous controller LT3740 is idealfor these applications, converting input supplies rangingfrom 2.2V to 22V to outputs as low as 0.8V with loadcurrents from 2A to 20A. Applications include distributedpower systems, point-of-load regulation and conversionof logic supplies.
上传时间: 2013-11-05
上传用户:zhf01y
Advances in low power electronics now allow placementof battery-powered sensors and other devices in locationsfar from the power grid. Ideally, for true grid independence,the batteries should not need replacement, but instead berecharged using locally available renewable energy, suchas solar power. This Design Note shows how to producea compact battery charger that operates from a small2-cell solar panel. A unique feature of this design is thatthe DC/DC converter uses power point control to extractmaximum power from the solar panel.
上传时间: 2014-01-20
上传用户:wettetw