Zero Drift, Bidirectional Current Shunt Monitor Data Sheet AD8218 FEATURES FUNCTIONAL BLOCK DIAGRAM V S High common-mode voltage range R4 4 V to 80 V operating AD8218 0.3 V to +85 V survival R1 Buffered output voltage IN OUT Gain = 20 V/V +IN Wide operating temperature range: 40C to +125C R2 LDO R3 Excellent ac and dc performance ENB 100 nV/C typical offset drift 50 V typical offset GND REF 5 ppm/C typical gain drift Figure 1. 110 dB typical CMRR at dc APPLICATIONS High-side current sensing 48 V telecom Power management Base stations Bidirectional motor control Precision high voltage current sources GENERAL DESCRIPTION The AD8218 is a high voltage, high resolution current shunt The AD8218 offers breakthrough performance throughout the amplifier. It features a set gain of 20 V/V, with a maximum 40C to +125C temperature range. It features a zero-drift core, 0.35% gain error over the entire temperature range. The which leads to a typical offset drift of 100 nV/C throughout buffered output voltage directly interfaces with any typical the operating temperature range and the common-mode voltage converter. The AD8218 offers excellent input common-mode range. Special attention is devoted to output linearity being rejection from 4 V to 80 V. The AD8218 performs bidirectional maintained throughout the input differential voltage range of current measurements across a shunt resistor in a variety of 0 mV to ~250 mV. The AD8218 also includes an internal 80 mV industrial and telecom applications, including motor control, reference that can be enabled for optimal dynamic range in battery management, and base station power amplifier bias unidirectional current sense applications. The typical input control. offset voltage is 50 V. The AD8218 is offered in an 8-lead MSOP package and an 8-lead LFCSP package. Rev. B 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 20112013 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. 09592-001AD8218 Data Sheet TABLE OF CONTENTS Features .............................................................................................. 1 Output Clamping ....................................................................... 10 Applications ....................................................................................... 1 Application Notes ........................................................................... 11 Functional Block Diagram .............................................................. 1 Supply (VS) Connections ........................................................... 11 General Description ......................................................................... 1 Enable Pin (ENB) Operation .................................................... 11 Revision History ............................................................................... 2 Applications Information .............................................................. 12 Specifications ..................................................................................... 3 Unidirectional High-Side Current Sensing ............................ 12 Absolute Maximum Ratings ............................................................ 4 Bidirectional High-Side Current Sensing ............................... 12 ESD Caution .................................................................................. 4 Motor Control Current Sensing ............................................... 12 Pin Configurations and Function Descriptions ........................... 5 Outline Dimensions ....................................................................... 13 Typical Performance Characteristics ............................................. 6 Ordering Guide .......................................................................... 13 Theory of Operation ...................................................................... 10 Amplifier Core ............................................................................ 10 REVISION HISTORY 4/13Rev. A to Rev. B Added 8-Lead LFCSP ......................................................... Universal Changes to General Description Section ...................................... 1 Added Figure 3, Renumbered Sequentially .................................. 5 Changes to Table 3 ............................................................................ 5 Added Figure 37 .............................................................................. 13 Updated Outline Dimensions ....................................................... 13 Changes to Ordering Guide .......................................................... 13 2/11Rev. 0 to Rev. A Changes to Features .......................................................................... 1 1/11Revision 0: Initial Version Rev. B Page 2 of 16