Datasheet AD8418A (Analog Devices)

Bidirectional, Zero Drift, Current Sense Amplifier Data Sheet AD8418A FEATURES GENERAL DESCRIPTION Typical 0.1 μV/°C offset drift
The AD8418A is a high voltage, high resolution current shunt
Maximum ±200 μV voltage offset over full temperature range
amplifier. It features an initial gain of 20 V/V, with a maximum
2.7 V to 5.5 V power supply operating range
±0.15% gain error over the entire temperature range. The buffered
Electromagnetic interference (EMI) filters included
output voltage directly interfaces with any typical converter. The
High common-mode input voltage range
AD8418A offers excellent input common-mode rejection from
−2 V to +70 V, continuous operation
−2 V to +70 V. The AD8418A performs bidirectional current
−3 V to +80 V, continuous survival
measurements across a shunt resistor in a variety of automotive
Minimum DC common-mode rejection ratio (CMRR): 90 dB
and industrial applications, including motor control, power
Initial gain = 20 V/V
management, and solenoid control.
Wide operating temperature range
The AD8418A offers breakthrough performance throughout
AD8418AWB: − 40°C to +125°C
the −40°C to +150°C temperature range. It features a zero drift
AD8418AWH: − 40°C to +150°C
core, which leads to a typical offset drift of 0.1 μV/°C throughout
Bidirectional operation
the operating temperature range and the common-mode voltage
Available in 8-lead SOIC and 8-lead MSOP
range. The AD8418A is qualified for automotive applications.
Qualified for automotive applications
The device includes EMI filters and patented circuitry to enable
APPLICATIONS
output accuracy with pulse-width modulation (PWM) type
High-side current sensing in
input common-mode voltages. The typical input offset voltage
Motor controls
is ±100 μV. The AD8418A is offered in 8-lead MSOP and SOIC
Solenoid controls
packages.
Power management Table 1. Related Devices Low-side current sensing Part No. Description Diagnostic protection
AD8205 Current sense amplifier, gain = 50 AD8206 Current sense amplifier, gain = 20 AD8207 High accuracy current sense amplifier, gain = 20 AD8210 High speed current sense amplifier, gain = 20 AD8417 High accuracy current sense amplifier, gain = 60
FUNCTIONAL BLOCK DIAGRAM VCM = –2V TO +70V VS = 2.7V TO 5.5V 70V V V S REF1 VOUT V V S CM AD8418A +IN EMI + I FILTER SHUNT 0V OUT G = 20 RSHUNT VS/2 –IN EMI – 50A FILTER ISHUNT 0V GND VREF2 –50A
01 0 83- 18 1 Figure 1.
Rev. D 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 rights of third parties that may result from its use. Specifications subject to change without notice. No One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Tel: 781.329.4700 ©2013–2018 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. Technical Support www.analog.com
Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION FUNCTIONAL BLOCK DIAGRAM TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS THEORY OF OPERATION OUTPUT OFFSET ADJUSTMENT UNIDIRECTIONAL OPERATION Ground Referenced Output Mode VS Referenced Output Mode BIDIRECTIONAL OPERATION EXTERNAL REFERENCED OUTPUT SPLITTING THE SUPPLY SPLITTING AN EXTERNAL REFERENCE APPLICATIONS INFORMATION MOTOR CONTROL 3-Phase Motor Control H-Bridge Motor Control SOLENOID CONTROL High-Side Current Sense with a Low-Side Switch High-Side Current Sense with a High-Side Switch High Rail Current Sensing OUTLINE DIMENSIONS ORDERING GUIDE AUTOMOTIVE PRODUCTS