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Dual 8-,10-,12-Bit High Bandwidth

Multiplying DACs with Serial Interface AD5429/AD5439/AD5449

Rev. 0 Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781.329.4700 www.analog.com Fax: 781.326.8703© 2004 Analog Devices, Inc. All rights reserved. FEATURES

10 MHz multiplying bandwidth

50 MHz serial interface

2.5 V to 5.5 V supply operation

±10 V reference input

Pin compatible 8-, 10-, and 12-bit DACs

Extended temperature range: −40°C to +125°C

16-lead TSSOP package

Guaranteed monotonic

Power-on reset

Daisy-chain mode

Readback function

0.5 µA typical current consumption

APPLICATIONS

Portable battery-powered applications

Waveform generators

Analog processing

Instrumentation applications

Programmable amplifiers and attenuators

Digitally controlled calibration

Programmable filters and oscillators

Composite video

Ultrasound

Gain, offset, and voltage trimming FUNCTIONAL BLOCK DIAGRAM

SYNCAD5429/AD5439/AD5449

VREFBVREFA

SCLKSDIN

IOUT1BIOUT1A8-/10-/12-BITR-2R DAC A

8-/10-/12-BITR-2R DAC BRFBA

POWER-ONRESETDACREGISTER

DACREGISTER

RFBRRFBR

IOUT2A

IOUT2B

LDAC04464-0-001VDD

CLR

RFBBINPUTREGISTER

INPUTREGISTERSHIFTREGISTER

LDACSDO

Figure 1.

GENERAL DESCRIPTION

The AD5429/AD5439/AD54491 are CMOS 8-, 10-, and 12-bit

dual-channel current output digital-to-analog converters,

respectively. These devices operate from a 2.5 V to 5.5 V power

supply, making them suited to battery-powered and other

applications.

The applied external reference input voltage (VREF) determines

the full-scale output current. An integrated feedback resistor

(RFB) provides temperature tracking and full-scale voltage

output when combined with an external current-to-voltage

precision amplifier.

These DACs utilize a double-buffered, 3-wire serial interface

that is compatible with SPI®, QSPI™, MICROWIRE™, and most

DSP interface standards. In addition, a serial data out pin (SDO)

allows daisy-chaining when multiple packages are used. Data

readback allows the user to read the contents of the DAC

register via the SDO pin. On power-up, the internal shift

register and latches are filled with zeros and the DAC outputs

are at zero scale.

As a result of manufacture on a CMOS submicron process,

these parts offer excellent 4-quadrant multiplication character-

istics, with large signal multiplying bandwidths of 10 MHz.

The AD5429/AD5439/AD5449 DAC are available in 16-lead

TSSOP packages.

1 US Patent Number 5,689,257.

元器件交易网www.cecb2b.comAD5429/AD5439/AD5449

Rev. 0 | Page 2 of 32 TABLE OF CONTENTS

Specifications.....................................................................................3

Timing Characteristics.....................................................................5

Absolute Maximum Ratings............................................................7

ESD Caution..................................................................................7

Pin Configuration and Function Descriptions.............................8

Terminology......................................................................................9

Typical Performance Characteristics...........................................10

General Description.......................................................................15

Unipolar Mode............................................................................15

Bipolar Operation.......................................................................16

Stability........................................................................................16

Single-Supply Applications........................................................17

Positive Output Voltage.............................................................17 Adding Gain................................................................................18

Divider or Programmable Gain Element................................18

Reference Selection....................................................................19

Amplifier Selection....................................................................19

Serial Interface................................................................................20

Microprocessor Interfacing.......................................................22

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AD623资料

AD623资料

摘要：本文在介绍了低噪声可变增益仪表放大器ad623的特点和工作原理的基础

上，进一步介绍了以ad623为核心的放大电路的数采系统。该数采系统提高了数

据采集系统的处理能力，降低了系统的功耗，同时改善了系统采集信号的信噪比。

关键词：ad623，增益，低噪声，数采系统

1引言

1.1 ad623简介

ad623 是一个集成单电源仪表放大器，它能在单电源( + 3v～ + 12v) 下提

供满电源幅度的输出,ad623 允许使用单个增益设置电阻进行增益编程,以得到

良好的用户灵活性。在无外接电阻的条件下,ad623 被设置为单位增益;外接电阻

后,ad623 可编程设置增益,其增益最高可达1000 倍。ad623 通过提供极好的随

增益增大而增大的交流共模抑制比(ac cmrr) 而保持最小的误差,线路噪声及谐

波将由于共模抑制比在高达200hz 时仍保持恒定而受到抑制。虽然ad623 在单

电源方式进行优化设计,但当它工作于双电源( ±2. 5～ ±6v) 时,仍能提供优

良的性能。低功耗(3v 时1. 5mw) 、宽电源电压范围、满电源幅度输出。其引

脚排列如图1所示。

图1 ad623引脚排列

1.2 ad623 工作原理

图2 为ad623 的原理图。输入信号加到作为电压缓冲器的pnp 晶体管上,并且

提供一个共模信号到输入放大器,每个放大器接入一个精确的50kω 的反馈电

阻,以保证增益可编程。差分输出为:

然后差分电压通过输出放大器转变为单端电压。6 脚的输出电压以5 脚的电位

为基准进行测量。基准端(5脚) 的阻抗是100kω ,在需要电压/ 电流转换的应

用中仅仅需要在5 脚与6 脚之间连接一只小电阻。+vs 和- vs 接双极性电源(vs

= ±2. 5v～ ±6v)或单电源( + vs = 3. 0v～12v , - vs = 0) 。靠近电源引

脚处加电容去耦。去耦电容最好选用0. 1μf 的瓷片电容和10μf 的钽电解电

AD8510中文资料

AD8510中文资料

AD8510ARZ-REEL7: 运算放大器SOIC-8封装

AD8510/AD8512/AD8513分别是单路、双路和四路精密JFET放大器,具有低失调电压、低输入偏置电流、低输入电压噪声和低输入电流噪声特性。

低失调、低噪声和极低输入偏置电流这些特性相结合,使这些放大器特别适合高阻抗传感器放大以及采用分流的精密电流测量。直流精度、低噪声和快速建立时间特性相结合,则使医疗仪器、电子测量和自动测试设备可以获得优异的精度。与许多竞争产品不同,即使容性负载相当大,AD8510/ AD8512/AD8513也能保持快速建立性能。不同于许多旧式JFET放大器,当输入电压超过最大共模电压范围时,AD8510/AD8512/AD8513不会发生输出反相。

AD8510/AD8512/AD8513在容性负载下仍提供快速压摆率和极高稳定性,因此非常适合高性能滤波器使用。低输入偏置电流、低失调和低噪声特性,使光二极管放大器电路具有较宽的动态范围。低噪声、低失真、高输出电流和出色的速度,则使AD8510/AD8512/AD8513成为音频应用的绝佳选择。

AD8510/AD8512均采用8引脚窄体SOIC_N和8引脚MSOP两种封装。MSOP封装器件仅提供卷带和卷盘形式。AD8513采用14引脚SOIC_N和TSSOP两种封装。

AD8510/AD8512/AD8513的额定温度范围均为−40°C至+125°C扩展工业温度范围。

The AD8510/AD8512/AD8513 are single-, dual-, and quad-precision JFET amplifiers that

feature low offset voltage, input bias current, input voltage noise, and input current noise.

The combination of low offsets, low noise, and very low input bias currents makes these

半导体传感器AD626ARZ中文规格书

半导体传感器AD626ARZ中文规格书

AD626–SPECIFICATIONSModel AD626A AD626BParameterConditionMin Typ Max Min Typ Max UnitGAINGain AccuracyTotal Error Gain = 10@ VOUT ≥ 100 mV dc0.4 1.00.2 0.6 % Gain = 100@ VOUT ≥ 100 mV dc0.1 1.00.5 0.6 %Over Temperature, TA = TMIN to TMAX G = 105030 ppm/°CG = 100150120 ppm/°CGain Linearity Gain = 10@ VOUT ≥ 100 mV dc0.014 0.0160.014 0.016 % Gain = 100@ VOUT ≥ 100 mV dc0.014 0.020.014 0.02 %OFFSET VOLTAGEInput Offset Voltage1.9 2.51.9 2.5 mV vs. TemperatureTMIN to TMAX, G = 10 or 100 2.92.9 mV vs. TemperatureTMIN to TMAX, G = 10 or 10066 µV/°C vs. Supply Voltage (PSR)+PSR74 80 74 80 dB–PSR64 66 64 66 dBCOMMON-MODE REJECTIONRL = 10 k⍀+CMR Gain = 10, 100f = 100 Hz, VCM = +24 V 66 90 80 90 dB±CMR Gain = 10, 100f = 10 kHz, VCM = +6 V 55 64 55 64 dB–CMR Gain = 10, 100*f = 100 Hz, VCM = –2 V60 85 73 85 dBCOMMON-MODE VOLTAGE RANGE+CMV Gain = 10CMR > 85 dB+24+24V–CMV Gain = 10CMR > 85 dB–2–2VINPUTInput Resistance Differential 200 200 k⍀ Common-Mode100 100 k⍀ Input Voltage Range (Common-Mode)6 (VS – l) 6 (VS – l) VOUTPUTOutput Voltage SwingRL = 10 k⍀ PositiveGain = 104.7 4.90 4.7 4.90 VGain = 1004.7 4.90 4.7 4.90 V NegativeGain = 100.03 0.03 VGain = 1000.03 0.03 VShort Circuit Current+ISC12 12 mANOISE Voltage Noise RTI Gain = 10f = 0.1 Hz–10 Hz2 2 µV p-p Gain = 100f = 0.1 Hz–10 Hz2 2 µV p-p Gain = 10f = 1 kHz0.25 0.25 µV/ͱHz Gain = 100f = 1 kHz0.25 0.25 µV/ͱHzDYNAMIC RESPONSE–3 dB BandwidthVOUT = +1 V dc100 100 kHzSlew Rate, TMIN to TMAXGain = 100.17 0.22 0.17 0.22 V/µsGain = 1000.1 0.17 0.1 0.17 V/µsSettling Timeto 0.01%, 1 V Step24 22 µsPOWER SUPPLYOperating RangeTA = TMIN to TMAX2.4 5 12 2.4 5 10 VQuiescent CurrentGain = 100.16 0.20 0.16 0.20 mAGain = 1000.23 0.290.23 0.29 mATRANSISTOR COUNTNumber of Transistors46 46*At temperatures above 25°C, –CMV degrades at the rate of 12 mV/°C; i.e., @ 25°C CMV = –2 V, @ 85°C CMV = –1.28 V.Specifi cations subject to change without notice.(@+VS = +5 V and TA = 25؇C, un less oth er wise noted.)SINGLE SUPPLY

AD5420

AD5420

Single Channel, 16-Bit, Serial Input, Current Source DAC

Preliminary Technical Data AD5420

Rev. PrD Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective owners. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.Tel: 781.329.4700 Fax: 781.461.3113 ©2007 Analog Devices, Inc. All rights reserved. FEATURES

16-Bit Resolution and Monotonicity

Current Output Ranges: 4–20mA, 0–20mA or 0–24mA