原标题：ADI AD4110－1工控系统通用输入模拟前端解决方案

　　ADI公司的AD4110-1是具有24位ADC的用于工业过程控制系统的通用输入模拟前端(AFE),所需的传感器类型是灵活性.高电压输入完全软件可配置电流和电压信号,并允许直接接口到所有标准的工业模拟信号源如±20 mA,±4 mA to±20 mA,±10 V以及所有的热电偶类型.现场电源可用来给回路供电的电流输出传感器,此外还包括电阻热电检测器(RTD)传感器和其它电阻型传感器的各种激励电流源.集成的全差分可编增益放大器(PGA)提供从0.2到24的16个增益设定点.高压输入可编程为电压模式或电流模式供电.在电流模式,独特的输入架构提供回路电流通路,甚至在缺少系统模块电源的情况下.AD4110-1提供内部前端诊断功能,以指明过压,欠压,开路,过流和超温状态.高压输入具有热保护功能,过流限制和过压保护.器件集成了精密的24位Σ-Δ模拟数转换器(ADC),转换速率从5SPS到125KSPS,同时有50Hz和60Hz的噪音抑制.4线接口和SPI®,QSPI™,MICROWIRE®以及DSP兼容,工作电压±12V到±20V,+5V,工作温度−40℃到+105℃.主要用在过程控制和工业自动化,遥控和分布式控制系统,仪器和测量,传感器和数据采集等.本文介绍了AD4110-1主要特性,功能框图,典型应用框图和多种应用电路,以及评估板EVAL-AD4110-1SDZ主要特性,功能框图,电路图和PCB设计图.

　　The AD4110-1 is a complete, single-channel, universal input analog-to-digital front end for industrial process control systems where sensor type flexibility is required. The high voltage input is fully software configurable for current or voltage signals and allows direct interface to all standard industrial analog signal sources such as ±20 mA, ±4 mA to ±20 mA, ±10 V, and all thermocouple types. Field power can be supplied for loop powered current output sensors. A range of excitation current sources for resistance temperature detector (RTD) sensors and other resistive sensors are included. The integrated, fully differential programmable gain amplifier (PGA) offers 16 gain settings from 0.2 to 24. The high voltage input can be programmed to power up in either voltage mode or current mode. When programmed to current mode, the unique input circuit architecture provides a path for the loop current, even in the absence of the system module power supply. The AD4110-1 provides internal, front-end diagnostic functions to indicate overvoltage, undervoltage, open wire, overcurrent, and overtemperature conditions. The high voltage input is thermally protected, overcurrent limited, and overvoltage protected. The AD4110-1 incorporates a precision 24-bit, Σ-Δ, analog-to- digital converter (ADC) offering conversion rates from 5 SPS to 125 kSPS with simultaneous 50 Hz and 60 Hz noise rejection.

　　AD4110-1主要特性:

　　2 software programmable input terminals

　　Current up to ±20 mA

　　Voltage up to ±10 V

　　Thermocouple

　　RTD

　　Replaces existing 3-terminal solutions

　　Field power supply for loop powered current sensors

　　HV input overvoltage protected up to ±30 V

　　Internal current sense resistor

　　Option to use external current sense resistor

　　Current limited input even with no power supply

　　Diagnostic functions for overrange and open wire detect

　　Fast and flexible output data rates: 5 SPS to 125 kSPS

　　16 noise free bits at 62 kSPS

　　18 noise free bits at 2.5 kSPS

　　20 noise free bits at 50 SPS/60 SPS

　　Simultaneous 50 Hz and 60 Hz rejection

　　Serial interface for configuration and diagnostics

　　4-wire interface compatible with SPI®, QSPI™, MICROWIRE®, and DSP

　　Power supply: ±12 V to ±20 V, +5 V

　　Operating temperature: −40℃ to +105℃

　　Package: 40-lead, 6 mm × 6 mm LFCSP

　　AD4110-1应用:

　　Process control and industrial automation

　　Remote and distributed control systems

　　Instrumentation and measurement

　　Sensor and data acquisition

图1.AD4110-1功能框图

图2.AD4110-1典型应用框图

图3.AD4110-1热电偶连接图

图4.AD4110-1 4线RTD连接图

图5.AD4110-13线RTD连接图

图6.AD4110-1 2线RTD连接图

　　评估板EVAL-AD4110-1SDZ

　　The EVAL-AD4110-1SDZ evaluates the features of the AD4110-1 analog front end (AFE). The software executable file of the PC controls the AD4110-1 via USB through the system demon- stration platform (SDP) board. The SDP-B board controls the evaluation board and can be connected to the USB port of any PC running Windows® 7, Windows 8, or Windows 10-based operating system using the AD4110-1 evaluation software. The AD4110-1 is a complete, single-channel, universal input, analog-to-digital front end for industrial process control systems where sensor type flexibility is required. The high voltage input is fully software configurable for current or voltage ranges and allow direct interface to all standard industrial analog signal sources, such as ±20 mA, ±4 mA to ±20 mA, ±10 V, and all thermocouple types. Field power can be supplied for loop powered current output sensors. A range of excitation current sources for resistance temperature detector (RTD) sensors and other resistive sensors are included. The integrated programmable gain amplifier (PGA) offers sixteen gain settings from 0.2 to 24.

　　评估板EVAL-AD4110-1SDZ主要特性:

　　Full-featured evaluation board for the AD4110-1

　　PC control in conjunction with Analog Devices, Inc., SDP

　　PC software for control Compatible with Windows 7, Windows 8, and Windows 10

　　评估板EVAL-AD4110-1SDZ包括:

　　EVAL-AD4110-1SDZ evaluation board

　　4 green screw block connectors, attached to the evaluation board

　　2 plastic screws and washers to bolt the EVAL-SDP-CB1Z to the EVAL-AD4110-1SDZ evaluation board

图7.评估板EVAL-AD4110-1SDZ功能框图

　　图8.硬件配置图-评估板EVAL-AD4110-1SDZ建立图

图9.评估板EVAL-AD4110-1SDZ电路图(1)

图10.评估板EVAL-AD4110-1SDZ电路图(2)

图11.评估板EVAL-AD4110-1SDZ电路图(3)