Universal Input Analog Front End with 24-Bit ADC for Industrial Process Control Systems Data Sheet AD4110-1 FEATURES GENERAL DESCRIPTION 2 software programmable input terminals The AD4110-1 is a complete, single-channel, universal input Current up to 20 mA analog-to-digital front end for industrial process control systems Voltage up to 10 V where sensor type flexibility is required. Thermocouple The high voltage input is fully software configurable for current RTD or voltage signals and allows direct interface to all standard Replaces existing 3-terminal solutions industrial analog signal sources such as 20 mA, 4 mA to Field power supply for loop powered current sensors 20 mA, 10 V, and all thermocouple types. Field power can be HV input overvoltage protected up to 30 V supplied for loop powered current output sensors. A range of Internal current sense resistor excitation current sources for resistance temperature detector Option to use external current sense resistor (RTD) sensors and other resistive sensors are included. The Current limited input even with no power supply integrated, fully differential programmable gain amplifier Diagnostic functions for overrange and open wire detect (PGA) offers 16 gain settings from 0.2 to 24. Fast and flexible output data rates: 5 SPS to 125 kSPS The high voltage input can be programmed to power up in 16 noise free bits at 62 kSPS either voltage mode or current mode. When programmed to 18 noise free bits at 2.5 kSPS current mode, the unique input circuit architecture provides a 20 noise free bits at 50 SPS/60 SPS path for the loop current, even in the absence of the system Simultaneous 50 Hz and 60 Hz rejection module power supply. Serial interface for configuration and diagnostics 4-wire interface compatible with SPI, QSPI, The AD4110-1 provides internal, front-end diagnostic functions MICROWIRE, and DSP to indicate overvoltage, undervoltage, open wire, overcurrent, and Power supply: 12 V to 20 V, +5 V overtemperature conditions. The high voltage input is thermally Operating temperature: 40C to +105C protected, overcurrent limited, and overvoltage protected. Package: 40-lead, 6 mm 6 mm LFCSP The AD4110-1 incorporates a precision 24-bit, -, analog-to- APPLICATIONS digital converter (ADC) offering conversion rates from 5 SPS to 125 kSPS with simultaneous 50 Hz and 60 Hz noise rejection. Process control and industrial automation Remote and distributed control systems Instrumentation and measurement Sensor and data acquisition FUNCTIONAL BLOCK DIAGRAM VDD VDD iREFS iREFF C(+) ADCAVDD AVDD5 AVDD5 REF() REF(+) REFOUT IOVDD IOVDD ADCDVDD FIELD iEXC SENSORS 1.8V 1.8V RTD LDO FIELD LDO NC RTD MUX REF VDD POWER SUPPLY OVERTEMPERATURE IN(+) CLKIO CLKIO SENSOR AIN(+) NO POWER CS MODE EXRF VSS SCLK DIGITAL PGA 24 BIT - ADC SWITCH FILTERING EXRS AFE/ADC DIN CONTROL PROCESSING SERIAL iCOMP VDD AND INTERFACE CONTROL CRC DOUT/RDY DIAGNOSTICS IN() CHANNEL SELECT AIN() ADR1 VBIAS ADR0 AD4110-1 VSS AGND SYNC AGND ERR VSS VSS VPP C() AIN1(LV) AIN2(LV) AINCOM(LV) DGND AGND AGND AGND Figure 1. Functional Block Diagram Rev. 0 Document Feedback 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 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. rights of third parties that may result from its use. Specifications subject to change without notice. No Tel: 781.329.4700 2019 Analog Devices, Inc. All rights reserved. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Technical Support www.analog.com Trademarks and registered trademarks are the property of their respective owners. 2-WIRE 3-WIRE 4-WIRE RTD 4mA TO 20mA TRANSMITTER 10V TRANSDUCER THERMOCOUPLE R SENSE R SENSE MULTIPLEXER 16269-001AD4110-1 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Input Auto Sequencing .............................................................. 21 Applications ....................................................................................... 1 Single Conversion Mode ........................................................... 22 General Description ......................................................................... 1 ADC Conversion Delay ............................................................. 22 Functional Block Diagram .............................................................. 1 Bias Voltage Generator .............................................................. 22 Revision History ............................................................................... 3 Antialiasing Filter Circuit .......................................................... 23 Specifications ..................................................................................... 4 Current Mode ............................................................................. 24 Timing Specifications .................................................................. 9 Voltage and Thermocouple Mode............................................ 27 Absolute Maximum Ratings .......................................................... 10 RTD Mode ................................................................................... 30 Thermal Resistance .................................................................... 10 Field Power Supply Mode .......................................................... 35 ESD Caution ................................................................................ 10 No Power Supply Mode ............................................................. 36 Pin Configuration and Function Descriptions ........................... 11 Gain Calibration Data Register .................................................... 38 Typical Performance Characteristics ........................................... 13 Gain Calibration in Voltage Mode ........................................... 38 Theory of Operation ...................................................................... 17 Gain Calibration in Current Mode .......................................... 38 Power Supply Sequence ............................................................. 18 Scaling Factor .............................................................................. 38 Protection Diode ........................................................................ 18 Autocalibration Modes .............................................................. 39 Analog Input ............................................................................... 18 Application Examples ................................................................ 40 Pull-Up/Pull-Down Currents ................................................... 18 Diagnostics and Protection ........................................................... 41 Antialiasing Filter ....................................................................... 18 Diagnostic Flags ......................................................................... 41 RTD Excitation Currents ........................................................... 18 Error Pin ...................................................................................... 41 Field Power Supply Mode .......................................................... 18 Overtemperature Detection and Thermal Shutdown ........... 41 No Power Supply Mode ............................................................. 18 Overvoltage and Undervoltage Detection .............................. 42 Bias Voltage Generator .............................................................. 18 Overvoltage Protection .............................................................. 42 PGA .............................................................................................. 18 Diagnosing Overvoltage and Undervoltage Conditions ....... 43 Calibration Registers .................................................................. 18 Open Wire Detection................................................................. 44 Serial Interface ............................................................................ 18 Diagnostics for RTD Measurements and RTD Flags ............ 44 Clock ............................................................................................ 18 Noise, Settling Time, and Digital Filtering ................................. 45 ADC ............................................................................................. 18 Digital Filter ................................................................................ 45 ADC Filter Registers .................................................................. 18 Sinc5 + Sinc1 Filter .................................................................... 45 ADC Gain and Offset Registers ................................................ 18 Sinc3 Filter ................................................................................... 45 Noise Performance and Resolution .............................................. 19 Enhanced 50 Hz and 60 Hz Rejection Filters ......................... 48 Modes of Operation ....................................................................... 20 RTD Mode Noise Performance ................................................ 50 Default Mode of Operation on Power-Up .............................. 20 Serial Peripheral Interface ............................................................. 51 Changing The Default Mode of Operation for Future Power- Resetting the AD4110-1 ............................................................ 51 Up Cycles ..................................................................................... 20 SPI Command to Communications Register ......................... 51 Power Supply Requirements ..................................................... 20 RDY DOUT/ Pin ......................................................................... 52 System Clock Requirements ..................................................... 20 Write Operation.......................................................................... 52 Bipolar and Unipolar Output .................................................... 21 Read Operation........................................................................... 53 Auxiliary Low Voltage Inputs ................................................... 21 Multiple Devices on the SPI Bus .............................................. 54 Digital Filter ................................................................................ 21 CRC Checksum .......................................................................... 55 Continuous Conversion Mode ................................................. 21 CRC Checksum Methods .......................................................... 55 Rev. 0 Page 2 of 74