Abstract: Many industrial/scientific/medical (ISM) band radio frequency (RF) products use crystal oscillators to generate areference for the phase-locked loop (PLL)-based local oscillator (LO). This tutorial provides a basic description of theISM-RF Crystal Calculator, which can be used to calculate various impacts on crystal frequency accuracy and startupmargin for such an LO.
上傳時間： 2013-11-15
上傳用戶：JasonC
Abstract: Alexander Graham Bell patented twisted pair wires in 1881. We still use them today because they work so well. In addition we have the advantage ofincredible computer power within our world. Circuit simulators and filter design programs are available for little or no cost. We combine the twisted pair and lowpassfilters to produce spectacular rejection of radio frequency interference (RFI) and electromagnetic interference (EMI). We also illustrate use of a precision resistorarray to produce a customizable differential amplifier. The precision resistors set the gain and common mode rejection ratios, while we choose the frequencyresponse.
上傳時間： 2014-11-26
上傳用戶：Vici
With more and more multi-frequency clocks being used in today's chips, especially in the communications field, it is often necessary to switch the source of a clock line while the chip is running.
上傳時間： 2013-10-10
上傳用戶：1214209695
Abstract: A perfect voltage reference produces a stable voltage independent of any external factors. Real-world voltagereferences, of course, are subject to errors caused by many external factors. One causeof these major errors istemperature. Without care, it is easy to operate a voltage reference outside its operating temperature range. Thisapplication note describes how references respond to temperature changes, and how self-heating can cause a voltagereference to operate outside its recommended temperature range. Once understood, this knowledge can then be used toavoid making this design error.
上傳時間： 2013-11-08
上傳用戶：xianglee
Abstract: This application note presents an overview of the operational characteristics of accurate I²C real-time clocks (RTCs),including the DS3231, DS3231M, and DS3232. It focuses on general application guidelines that facilitate use of device resources forpower management, I²C communication circuit configurations, and I²C characteristics relative to device power-up sequences andinitializations. Additional discussions on decoupling are provided to support developing strategies for mitigating power-supply pushingof device frequency.
上傳時間： 2013-11-23
上傳用戶：WMC_geophy
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
上傳時間： 2013-11-13
上傳用戶：ca05991270
Abstract: IC switches and multiplexers are proliferating, thanks to near-continual progress in lowering the supply voltage,incorporating fault-protected inputs, clamping the output voltage, and reducing the switch resistances. The latest of these advancesis the inclusion of precision resistors to allow two-point calibration of gain and offset in precision data-acquisition systems.
上傳時間： 2013-11-12
上傳用戶：acwme
Abstract: This tutorial discusses methods for digitally adjusting the output voltage of a DC-DC converter. The digital adjustmentmethods are with a digital-to-analog converter (DAC), a trim pot (digital potentiometer), and PWM output of a microprocessor.Each method is assessed and several DACs and digital potentiometers presented.
上傳時間： 2013-11-20
上傳用戶：zycidjl
The purpose of this application note is to show an example of how a digital potentiometer can be used in thefeedback loop of a step-up DC-DC converter to provide calibration and/or adjustment of the output voltage.The example circuit uses a MAX5025 step-up DC-DC converter (capable of generating up to 36V,120mWmax) in conjunction with a DS1845, 256 position, NV digital potentiometer. For this example, the desiredoutput voltage is 32V, which is generated from an input supply of 5V. The output voltage can be adjusted in35mV increments (near 32V) and span a range wide enough to account for resistance, potentiometer and DCDCconverter tolerances (27.6V to 36.7V).
標簽： DC-DC 數(shù)字電位器 升壓型 校準
上傳時間： 2014-12-23
上傳用戶：781354052
Abstract: Transimpedance amplifiers (TIAs) are widely used to translate the current output of sensors like photodiode-to-voltagesignals, since several circuits and instruments can only accept voltage input. An operational amplifier with a feedback resistor fromoutput to the inverting input is the most straightforward implementation of such a TIA. However, even this simple TIA circuit requirescareful trade-offs among noise gain, offset voltage, bandwidth, and stability. Clearly stability in a TIA is essential for good, reliableperformance. This application note explains the empirical calculations for assessing stability and then shows how to fine-tune theselection of the feedback phase-compensation capacitor.
標簽： Transimpedance Stabilize Amplifier Your
上傳時間： 2013-11-13
上傳用戶：daoyue
