Abstract: Many digital devices incorporate analog circuits. For instance, microprocessors, applicationspecificintegrated circuits (ASICs), and field-programmable gate arrays (FPGAs) may have internalvoltage references, analog-to-digital converters (ADCs) or digital-to-analog converters (DACs). However,there are challenges when you integrate more analog onto a digital design. As with all things in life, inelectronics we must always trade one parameter for another, with the application dictating the propertrade-off of analog function. In this application note, we examine how the demand for economy of spaceand cost pushes analog circuits onto digital substrates, and what design challenges emerge.
上传时间: 2013-11-17
上传用户:菁菁聆听
The trend in ADCs and DACs is toward higher speeds and higher resolutions atreduced power levels. Modern data converters generally operate on ±5V (dualsupply) or +5V (single supply). In fact, many new converters operate on a single +3Vsupply. This trend has created a number of design and applications problems whichwere much less important in earlier data converters, where ±15V supplies and ±10Vinput ranges were the standard.
上传时间: 2013-11-16
上传用户:sjw920325
Many 8-bit and 16-bit microcontrollers feature 10-bitinternal ADCs. A few include 12-bit ADCs, but these oftenhave poor or nonexistent AC specifi cations, and certainlylack the performance to meet the needs of an increasingnumber of applications. The LTC®2366 and its slowerspeed versions offer a high performance alternative, asshown in the AC specifi cations in Table 1. Compare theseguaranteed specifi cations with the ADC built into yourcurrent microcontroller.
上传时间: 2013-10-26
上传用户:jackandlee
The STM32F10xxx microcontroller family embeds up to three advanced 12-bit ADCs (depending on the device) with a conversion time down to 1 μs. A self-calibration feature is provided to enhance ADC accuracy versus environmental condition changes.
上传时间: 2014-12-23
上传用户:eastimage
ANALOG INPUT BANDWIDTH is a measure of the frequencyat which the reconstructed output fundamental drops3 dB below its low frequency value for a full scale input. Thetest is performed with fIN equal to 100 kHz plus integer multiplesof fCLK. The input frequency at which the output is −3dB relative to the low frequency input signal is the full powerbandwidth.APERTURE JITTER is the variation in aperture delay fromsample to sample. Aperture jitter shows up as input noise.APERTURE DELAY See Sampling Delay.BOTTOM OFFSET is the difference between the input voltagethat just causes the output code to transition to the firstcode and the negative reference voltage. Bottom Offset isdefined as EOB = VZT–VRB, where VZT is the first code transitioninput voltage and VRB is the lower reference voltage.Note that this is different from the normal Zero Scale Error.CONVERSION LATENCY See PIPELINE DELAY.CONVERSION TIME is the time required for a completemeasurement by an analog-to-digital converter. Since theConversion Time does not include acquisition time, multiplexerset up time, or other elements of a complete conversioncycle, the conversion time may be less than theThroughput Time.DC COMMON-MODE ERROR is a specification which appliesto ADCs with differential inputs. It is the change in theoutput code that occurs when the analog voltages on the twoinputs are changed by an equal amount. It is usually expressed in LSBs.
上传时间: 2013-11-12
上传用户:pans0ul
Abstract: Many modern industrial, medical, and commercial applications require temperature measurements in the extended temperature rangewith accuracies of ±0.3°C or better, performed with reasonable cost and often with low power consumption. This article explains how platinumresistance temperature detectors (PRTDs) can perform measurements over wide temperature ranges of -200°C to +850°C, with absolute accuracyand repeatability better than ±0.3°C, when used with modern processors capable of resolving nonlinear mathematical equation quickly and costeffectively. This article is the second installment of a series on PRTDs. For the first installment, please read application note 4875, "High-Accuracy Temperature Measurements Call for Platinum Resistance Temperature Detectors (PRTDs) and Precision Delta-Sigma ADCs."
上传时间: 2013-11-06
上传用户:WMC_geophy
Delta-sigma ADCs, with their high accuracy and high noiseimmunity, are ideal for directly measuring many typesof sensors. Nevertheless, input sampling currents canoverwhelm high source impedances or low-bandwidth,micropower signal conditioning circuits. The LTC®2484family of delta sigma converters solves this problem bybalancing the input currents, thussimplifying or eliminatingthe need for signal conditioning circuits.
上传时间: 2015-01-03
上传用户:潜水的三贡
The TAS3204 is a highly-integrated audio system-on-chip (SOC) consisting of a fully-programmable, 48-bit digital audio processor, a 3:1 stereo analog input MUX, four ADCs, four DACs, and other analog functionality. The TAS3204 is programmable with the graphical PurePath Studio™ suite of DSP code development software. PurePath Studio is a highly intuitive, drag-and-drop environment that minimizes software development effort while allowing the end user to utilize the power and flexibility of the TAS3204’s digital audio processing core. TAS3204 processing capability includes speaker equalization and crossover, volume/bass/treble control, signal mixing/MUXing/splitting, delay compensation, dynamic range compression, and many other basic audio functions. Audio functions such as matrix decoding, stereo widening, surround sound virtualization and psychoacoustic bass boost are also available with either third-party or TI royalty-free algorithms. The TAS3204 contains a custom-designed, fully-programmable 135-MHz, 48-bit digital audio processor. A 76-bit accumulator ensures that the high precision necessary for quality digital audio is maintained during arithmetic operations. Four differential 102 dB DNR ADCs and four differential 105 dB DNR DACs ensure that high quality audio is maintained through the whole signal chain as well as increasing robustness against noise sources such as TDMA interference. The TAS3204 is composed of eight functional blocks: Clocking System Digital Audio Interface Analog Audio Interface Power supply Clocks, digital PLL I2C control interface 8051 MCUcontroller Audio DSP – digital audio processing 特性 Digital Audio Processor Fully Programmable With the Graphical, Drag-and-Drop PurePath Studio™ Software Development Environment 135-MHz Operation 48-Bit Data Path With 76-Bit Accumulator Hardware Single-Cycle Multiplier (28 × 48)
上传时间: 2016-05-06
上传用户:fagong
Microprocessors are getting smaller, cheaper and faster. Every day, it is easier to embed more functionality into a smaller space. Embedded processors have become pervasive, and as time goes on, more and more functions that were once implemented with analog circuitry or with electromechanical assemblies are being realized with microcontrollers, ADCs and DACs. Many of these assemblies that are being supplanted by the microprocessor are controlling dynamic processes, which is a good thing, because the microprocessor coupled with the right software is often the superior device.
上传时间: 2016-07-20
上传用户:kunger
The continued reduction of integrated circuit feature sizes and commensurate improvements in device performance are fueling the progress to higher functionality and new application areas. For example, over the last 15 years, the performance of microprocessors has increased 1000 times. Analog circuit performance has also improved, albeit at a slower pace. For example, over the same period the speed/resolution figure-of-merit of analog-to-digital converters improved by only a factor 10.
标签: Digitally Assisted Pipeline ADCs
上传时间: 2020-05-27
上传用户:shancjb