18-Bit, 1.33 MSPS PulSAR 10.5 mW ADC in MSOP/LFCSP Data Sheet AD7984 FEATURES APPLICATION DIAGRAM 2.9V TO 5V 2.5V High performance True differential analog input range: V REF 0 V to V with V between 2.9 V to 5 V REF REF 1.8V TO 5V VIO REF VDD Easy to drive with the ADA4941 IN+ SDI 3- OR 4-WIRE Throughput: 1.33 MSPS AD7984 SCK INTERFACE 10V, 5V, .. Zero latency architecture (SPI, CS SDO IN DAISY CHAIN) GND CNV ADA4941 18-bit resolution with no missing codes INL: 2.25 LSB maximum Dynamic range: 99.7 dB, V = 5 V Figure 1. REF SNR: 98.5 dB at f = 1 kHz, V = 5 V IN REF GENERAL DESCRIPTION THD: 110.5 dB at f = 1 kHz, V = 5 V IN REF 1 The AD7984 is an 18-bit, successive approximation, analog-to- SINAD: 97.5 dB at f = 1 kHz, V = 5 V IN REF digital converter (ADC) that operates from a single power supply, Low power dissipation VDD. It contains a low power, high speed, 18-bit sampling ADC Single-supply 2.5 V operation with 1.8 V/2.5 V/3 V/5 V and a versatile serial interface port. On the CNV rising edge, logic interface the AD7984 samples the voltage difference between the IN+ 5.3 mW at 1.33 MSPS (VDD only) and IN pins. The voltages on these pins usually swing in 10.5 mW at 1.33 MSPS (total) opposite phases between 0 V and VREF. The reference voltage, 80 W at 10 kSPS REF, is applied externally and can be set independent of the Proprietary serial interface supply voltage, VDD. SPI/QSPI/MICROWIRE/DSP compatible Ability to daisy-chain multiple ADCs and busy indicator The SPI-compatible serial interface also features the ability, 10-lead MSOP and 10-lead, 3 mm 3 mm LFCSP using the SDI input, to daisy-chain several ADCs on a single Wide operating temperature range: 40C to +85C 3-wire bus and provides an optional busy indicator. It is compatible with 1.8 V, 2.5 V, 3 V, and 5 V logic, using the separate APPLICATIONS VIO supply. Automated test equipment The AD7984 is available in a 10-lead MSOP or a 10-lead LFCSP Data acquisition systems with operation specified from 40C to +85C. Medical instruments 1 Protected by U.S. Patent 6,703,961. Machine automation Table 1. MSOP, LFCSP 16-/18-/20-Bit Precision SAR ADCs and SAR ADC-Based Module Data Acquisition Solutions Type 100 kSPS 250 kSPS 500 kSPS 1000 kSPS 2000 kSPS Module Data Acquisition Solutions Differential 1 1 1 20-Bit AD4022 AD4021 AD4020 1 1 1 1 1 18-Bit AD7989-1 AD7691 AD4011 AD4007 AD4003 1 1 AD7690 AD7982 1 1 AD7989-5 AD7984 1 1 1 1 16-Bit AD7684 AD7687 AD7688 AD4005 AD4001 1 1 AD7693 AD7915 1 AD7916 Pseudo Differential 1 1 1 18-Bit AD4010 AD4006 AD4002 1 1 1 1 1 16-Bit AD7988-1 AD7685 AD4008 AD4004 AD4000 ADAQ7980 1 1 AD7680 AD7694 AD7988-5 AD7980 ADAQ7988 1 1 AD7683 AD7686 AD7983 1 Pin for pin compatible. Rev. C 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. Tel: 781.329.4700 20072020 Analog Devices, Inc. All rights reserved. No license is granted by implication or otherwise under any patent or patent rights of Analog Technical Support www.analog.com Devices. Trademarks and registered trademarks are the property of their respective owners. 06973-001AD7984 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Driver Amplifier Choice ........................................................... 15 Applications ...................................................................................... 1 Single-to-Differential Driver .................................................... 16 Application Diagram ....................................................................... 1 Voltage Reference Input ............................................................ 16 General Description ......................................................................... 1 Power Supply .............................................................................. 16 Revision History ............................................................................... 2 Digital Interface .......................................................................... 17 Specifications .................................................................................... 3 CS Mode, 3-Wire Without Busy Indicator............................. 18 Timing Specifications .................................................................. 5 CS Mode, 3-Wire with Busy Indicator .................................... 19 Absolute Maximum Ratings ........................................................... 7 CS Mode, 4-Wire Without Busy Indicator............................. 20 Thermal Resistance ...................................................................... 7 CS Mode, 4-Wire with Busy Indicator .................................... 21 ESD Caution.................................................................................. 7 Chain Mode Without Busy Indicator ..................................... 22 Pin Configurations and Function Descriptions ........................... 8 Chain Mode with Busy Indicator ............................................. 23 Typical Performance Characteristics ............................................. 9 Application Hints ........................................................................... 24 Terminology .................................................................................... 12 Layout .......................................................................................... 24 Theory of Operation ...................................................................... 13 Evaluating the AD7984 Performance ...................................... 24 Circuit Information ................................................................... 13 Outline Dimensions ....................................................................... 25 Converter Operation .................................................................. 13 Ordering Guide .......................................................................... 25 Typical Connection Diagram ................................................... 14 Analog Inputs ............................................................................. 15 REVISION HISTORY 7/2020Rev. B to Rev. C 7/2014Rev. A to Rev. B Changes to Features Section, Applications Section, and Changed QFN (LFCSP) to LFCSP .............................. Throughout Table 1 ................................................................................................ 1 Changes to Features Section and Table 1 ...................................... 1 Changes to Specifications Section and Table 2 ............................ 3 Added Patent Note, Note 1 .............................................................. 1 Changes to Power Supplies Parameter, Table 3 ........................... 4 Changes to Power Supply Section ................................................ 15 Changes to Timing Specifications Section and Table 4 .............. 5 Changes to Evaluating the AD7984 Performance Section ....... 23 Added Table 5 Renumbered Sequentially .................................... 6 Updated Outline Dimensions ...................................................... 24 Deleted Figure 3 Renumbered Sequentially ................................ 6 Changes to Ordering Guide .......................................................... 24 Changes to Table 6 ........................................................................... 7 Added Thermal Resistance Section and Table 7 .......................... 7 8/2010Rev. 0 to Rev. A Changes to Figure 22 ..................................................................... 14 Updated Outline Dimensions ...................................................... 24 Changes to Driver Amplifier Choice Section and Table 10 ..... 15 Changes to Ordering Guide .......................................................... 24 Changes to Single-to-Differential Driver Section, Voltage Reference Input Section, and Power Supply Section ................. 16 11/2007Revision 0: Initial Version Rev. C Page 2 of 25