Isolated Sigma-Delta Modulator Data Sheet AD7400A FEATURES GENERAL DESCRIPTION 1 10 MHz clock rate The AD7400A is a second-order, - modulator that converts Second-order modulator an analog input signal into a high speed, 1-bit data stream with 16 bits, no missing codes on-chip digital isolation based on Analog Devices, Inc., iCoupler 2 LSB INL typical at 16 bits technology. The AD7400A operates from a 5 V power supply 1.5 V/C typical offset drift and accepts a differential input signal of 250 mV (320 mV On-board digital isolator full-scale). The analog input is sampled continuously by the On-board reference analog modulator, eliminating the need for external sample- 250 mV analog input range and-hold circuitry. The input information is contained in the Low power operation: 15.5 mA typical at 5.5 V output stream as a density of ones with a data rate of 10 MHz. 40C to +125C operating range The original information can be reconstructed with an appropriate 16-lead SOIC package digital filter. The serial I/O can use a 5 V or a 3 V supply (VDD2). AD7401A, external clock version in 16-lead SOIC The serial interface is digitally isolated. High speed CMOS, Safety and regulatory approvals combined with monolithic air core transformer technology, UL recognition means the on-chip isolation provides outstanding performance 5000 V rms for 1 minute per UL 1577 characteristics superior to alternatives such as optocoupler CSA Component Acceptance Notice 5A devices. The part contains an on-chip reference and has an VDE Certificate of Conformity operating temperature range of 40C to +125C. The AD7400A DIN V VDE V 0884-10 (VDE V 0884-10):2006-12 is offered in a 16-lead SOIC package. V = 891 V peak IORM 1 Protected by U.S. Patents 5,952,849 6,873,065 and 7,075,329. APPLICATIONS AC motor controls Shunt current monitoring Data acquisition systems Analog-to-digital and opto-isolator replacements FUNCTIONAL BLOCK DIAGRAM V V DD1 DD2 AD7400A V + IN - ADC V IN UPDATE WATCHDOG ENCODE DECODE MDAT REF CONTROL LOGIC UPDATE WATCHDOG ENCODE MCLKOUT DECODE GND GND 1 2 Figure 1. Rev. E 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 20082018 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. T/H BUF 07077-001AD7400A Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Terminology .................................................................................... 12 Applications ....................................................................................... 1 Theory of Operation ...................................................................... 13 General Description ......................................................................... 1 Circuit Information .................................................................... 13 Functional Block Diagram .............................................................. 1 Analog Input ............................................................................... 13 Revision History ............................................................................... 2 Differential Inputs ...................................................................... 14 Specifications ..................................................................................... 3 Current Sensing Applications ................................................... 14 Timing Specifications .................................................................. 4 Voltage Sensing Applications .................................................... 14 Insulation and Safety-Related Specifications ............................ 5 Digital Filter ................................................................................ 15 Regulatory Information ............................................................... 5 Applications Information .............................................................. 17 DIN V VDE V 0884-10 (VDE V 0884-10) Insulation Grounding and Layout .............................................................. 17 Characteristics .............................................................................. 6 Evaluating the AD7400A Performance ................................... 17 Absolute Maximum Ratings ............................................................ 7 Insulation Lifetime ..................................................................... 17 ESD Caution .................................................................................. 7 Outline Dimensions ....................................................................... 18 Pin Configuration and Function Descriptions ............................. 8 Ordering Guide .......................................................................... 18 Typical Performance Characteristics ............................................. 9 REVISION HISTORY 4/2018Rev. D to Rev. E 9/2008Rev. 0 to Rev. A Changes to Table 3 and Table 4 ....................................................... 5 Added 16-Lead SOIC ......................................................... Universal Changes to General Description Section ....................................... 1 11/2012Rev. C to Rev. D Changes to Table 1, Test Conditions/Comments Column .......... 3 Deleted 8-Lead PDIP ......................................................... Universal Changes to Timing Specifications Table Summary ...................... 4 Change to Note 1 .............................................................................. 1 Changes to Table 4, Note 2 ............................................................... 5 Deleted Figure 5 and Renumbered Sequentially .......................... 8 Added Figure 6 Renumbered Sequentially ................................... 8 Updated Outline Dimensions ....................................................... 18 Changes to Terminology Section ................................................. 12 Changes to Ordering Guide .......................................................... 18 Updated Outline Dimensions ....................................................... 18 Changes to Ordering Guide .......................................................... 18 7/2011Rev. B to Rev. C Changes to Minimum External Air Gap (Clearance) Parameter, 5/2008Revision 0: Initial Version Table 3 and Minimum External Tracking (Creepage) Parameter, Table 3 ................................................................................................ 5 Changes to Figure 6 Pin 1 Description, Table 8 and Pin 7 Description, Table 8 .......................................................................... 8 1/2011Rev. A to Rev. B Changed UL Recognition from 3750 V rms to 5000 V rms ....... 1 Changes to Input-to-Output Momentary Withstand Voltage Value (Table 3) .................................................................................. 5 Changed UL Recognition from 3750 V rms to 5000 V rms (Table 4) ............................................................................................. 5 Changes to Note 1 (Table 4) ............................................................ 5 Rev. E Page 2 of 18