The MAX5713/MAX5714/MAX5715 4-channel, low-power,8-/10-/12-bit, voltage-output digital-to-analog converters(DACs) include output buffers and an internal referencethat is selectable to be 2.048V, 2.500V, or 4.096V. TheMAX5713/MAX5714/MAX5715 accept a wide supplyvoltage range of 2.7V to 5.5V with extremely low power(3mW) consumption to accommodate most low-voltageapplications. A precision external reference input allowsrail-to-rail operation and presents a 100kI (typ) load toan external reference.
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.
Abstract: This article discusses application circuits for Maxim force/sense digital-to-analog converters (DACs). Applications include:selectable fixed-gain DAC, programmable gain DAC, photodiode bias control, amperometric sensor control, digitally programmablecurrent source, Kelvin load sensing, temperature sensing, and high current DAC output. A brief description of the various DAC outputconfigurations is also given.
Digital-to-analog converters (DACs) are prevalent inindustrial control and automated test applications.General-purpose automated test equipment often requiresmany channels of precisely controlled voltagesthat span several voltage ranges. The LTC2704 is ahighly integrated 16-bit, 4-channel DAC for high-endapplications. It has a wide range of features designed toincrease performance and simplify design.
Differential Nonlinearity: Ideally, any two adjacent digitalcodes correspond to output analog voltages that are exactlyone LSB apart. Differential non-linearity is a measure of theworst case deviation from the ideal 1 LSB step. For example,a DAC with a 1.5 LSB output change for a 1 LSB digital codechange exhibits 1⁄2 LSB differential non-linearity. Differentialnon-linearity may be expressed in fractional bits or as a percentageof full scale. A differential non-linearity greater than1 LSB will lead to a non-monotonic transfer function in aDAC.Gain Error (Full Scale Error): The difference between theoutput voltage (or current) with full scale input code and theideal voltage (or current) that should exist with a full scale inputcode.Gain Temperature Coefficient (Full Scale TemperatureCoefficient): Change in gain error divided by change in temperature.Usually expressed in parts per million per degreeCelsius (ppm/°C).Integral Nonlinearity (Linearity Error): Worst case deviationfrom the line between the endpoints (zero and full scale).Can be expressed as a percentage of full scale or in fractionof an LSB.LSB (Lease-Significant Bit): In a binary coded system thisis the bit that carries the smallest value or weight. Its value isthe full scale voltage (or current) divided by 2n, where n is theresolution of the converter.Monotonicity: A monotonic function has a slope whose signdoes not change. A monotonic DAC has an output thatchanges in the same direction (or remains constant) for eachincrease in the input code. the converse is true for decreasing codes.
特點(diǎn)(FEATURES) 精確度0.1%滿刻度 (Accuracy 0.1%F.S.) 可作各式數(shù)學(xué)演算式功能如:A+B/A-B/AxB/A/B/A&B(Hi or Lo)/|A| (Math functioA+B/A-B/AxB/A/B/A&B(Hi&Lo)/|A|/etc.....) 16 BIT 類比輸出功能(16 bit DAC isolating analog output function) 輸入/輸出1/輸出2絕緣耐壓2仟伏特/1分鐘(Dielectric strength 2KVac/1min. (input/output1/output2/power)) 寬范圍交直流兩用電源設(shè)計(jì)(Wide input range for auxiliary power) 尺寸小,穩(wěn)定性高(Dimension small and High stability)
為提高電容測(cè)量精度，針對(duì)電容式傳感器的工作原理設(shè)計(jì)了基于PIC16LF874單片機(jī)電容測(cè)量模塊。簡(jiǎn)單闡述了電容測(cè)量電路的應(yīng)用背景和國內(nèi)外研究現(xiàn)狀，介紹了美國Microchip公司PIC16LF874單片機(jī)的特性。電容式傳感器輸出的動(dòng)態(tài)微弱電容信號(hào)通過PS021型電容數(shù)字轉(zhuǎn)換器把模擬量數(shù)據(jù)轉(zhuǎn)換成數(shù)字量數(shù)據(jù)，所測(cè)數(shù)據(jù)由PIC16LF874單片機(jī)應(yīng)用程序進(jìn)行處理、顯示和保存。實(shí)驗(yàn)結(jié)果表明，固定電容標(biāo)稱值為10~20 pF 的測(cè)量值相對(duì)誤差在1%以內(nèi)，同時(shí)也可知被測(cè)電容容值越大，測(cè)量值和標(biāo)稱值相對(duì)誤差越小。
Abstract:
To improve the accuracy of capacitance measurement，aimed at the principle of work of mercury capacitance acceleration transducer，the design of micro capacitance measurement circuit is based on the key PIC16LF874 chip. Briefly discusses the application of the capacitance measuring circuit for the background and status of foreign researchers，focusing on the United States PIC16LF874 microcontroller features. Capacitive sensor outputed signal through the dynamics of weak PS021-chip capacitors （capacitancedigital converter） to convert analog data into digital data，the measured data from the PIC16LF874 microcontroller application process， display and preservation. Experimental results show that the fixed capacitor 10pF ~ 20pF nominal value of the measured value of relative error is within 1%，but also it canbe seen the value of the measured capacitance larger，measuring value and the nominal value of relative error smaller.
The SDI standards are the predominant standards for uncompressed digital videointerfaces in the broadcast studio and video production center. The first SDI standard,SD-SDI, allowed standard-definition digital video to be transported over the coaxial cableinfrastructure initially installed in studios to carry analog video. Next, HD-SDI wasto support high-definition video. Finally, dual link HD-SDI and 3G-SDIdoubled the bandwidth of HD-SDI to support 1080p (50 Hz and 60 Hz) and other videoformats requiring more bandwidth than HD-SDI provides.
The SDI standards are the predominant standards for uncompressed digital videointerfaces in the broadcast studio and video production center. The first SDI standard,SD-SDI, allowed standard-definition digital video to be transported over the coaxial cableinfrastructure initially installed in studios to carry analog video. Next, HD-SDI wasto support high-definition video. Finally, dual link HD-SDI and 3G-SDIdoubled the bandwidth of HD-SDI to support 1080p (50 Hz and 60 Hz) and other videoformats requiring more bandwidth than HD-SDI provides.
