ANALOG DEVICES AD8211 Service Manual

High Voltage

V

V

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FEATURES

±4000 V HBM ESD
High common-mode voltage range

−2 V to +65 V operating

−3 V to +68 V survival
Buffered output voltage
Wide operating temperature range

5-lead SOT: −40°C to +125°C

Excellent ac and dc performance

5 μV/°C typical offset drift

−13 ppm/°C typical gain drift

120 dB typical CMRR at dc

APPLICATIONS

High-side current sensing

Motor controls
Transmission controls
Engine management
Suspension controls
Vehicle dynamic controls
DC-to-dc converters

Current Shunt Monitor

AD8211

FUNCTIONAL BLOCK DIAGRAM

IN+

A1

GND

IN–

PROPRIETARY

OFFSET

CIRCUITRY

G = +20

AD8211

Figure 1.

V+

OUT

06824-001

GENERAL DESCRIPTION

The AD8211 is a high voltage, precision current shunt amplifier.
It features a set gain of 20 V/V, with a typical ±0.5% gain error
over the entire temperature range. The buffered output voltage
directly interfaces with any typical converter. Excellent common­mode rejection from −2 V to +65 V is independent of the 5 V
supply. The AD8211 performs unidirectional current measure­ments across a shunt resistor in a variety of industrial and
automotive applications, such as motor control, solenoid
control, or battery management.

Special circuitry is devoted to output linearity being maintained
t

hroughout the input differential voltage range of 0 mV to 250 mV,
regardless of the common-mode voltage present. The AD8211
has an operating temperature range of −40°C to +125°C and is
offered in a small 5-lead SOT package.

Rev. 0

Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Anal og Devices for its use, nor for any infringements of patents or ot her
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] ©2007 Analog Devices, Inc. All rights reserved.

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TABLE OF CONTENTS

Features .............................................................................................. 1

Applications....................................................................................... 1

Functional Block Diagram .............................................................. 1

General Description......................................................................... 1

Revision History ............................................................................... 2

Specifications..................................................................................... 3

Absolute Maximum Ratings............................................................ 4

ESD Caution.................................................................................. 4

Pin Configuration and Function Descriptions............................. 5

Typical Performance Characteristics ............................................. 6

REVISION HISTORY

7/07—Revision 0: Initial Version

Theory of Operation ...................................................................... 10

Application Notes ........................................................................... 11

Output Linearity......................................................................... 11

Applications Information.............................................................. 12

High-Side Current Sense with a Low-Side Switch................. 12

High-Side Current Sensing....................................................... 12

Low-Side Current Sensing ........................................................ 12

Outline Dimensions ....................................................................... 13

Ordering Guide .......................................................................... 13

Rev. 0 | Page 2 of 16

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SPECIFICATIONS

T

= −40°C to +125°C, TA = 25°C, VS = 5 V, RL = 25 kΩ (RL is the output load resistor), unless otherwise noted.

OPR

Table 1.

Parameter Min Typ Max Unit Conditions
GAIN

Initial 20 V/V

Accuracy ±0.25 % VO ≥ 0.1 V dc
Accuracy Over Temperature ±0.35 % T
Gain vs. Temperature −13 ppm/°C T

VOLTAGE OFFSET

Offset Voltage (RTI) ±1 mV 25°C
Over Temperature (RTI) ±2.2 mV T
Offset Drift 5 μV/°C T

INPUT

Input Impedance

Differential 5 kΩ
Common Mode 5 MΩ Common-mode voltage > 5 V

3.5 kΩ Common-mode voltage < 5 V
Common-Mode Input Voltage Range −2 +65 V Common-mode continuous
Differential Input Voltage Range 250 mV Differential input voltage
Common-Mode Rejection 100 120 dB TA, f = dc, VCM > 5 V, see Figure 5
80 90 dB TA, f = dc, VCM < 5 V, see Figure 5

OUTPUT

Output Voltage Range Low 0.1 0.05 V
Output Voltage Range High 4.95 4.9 V
Output Impedance 2 Ω

DYNAMIC RESPONSE

Small Signal −3 dB Bandwidth 500 kHz
Slew Rate 4.5 V/μs

NOISE

0.1 Hz to 10 Hz, RTI 7 μV p-p
Spectral Density, 1 kHz, RTI 70 nV/√Hz

POWER SUPPLY

Operating Range 4.5 5.5 V
Quiescent Current Over Temperature 1.2 2.0 mA VCM > 5 V3, see Figure 12
Power Supply Rejection Ratio 76 dB

TEMPERATURE RANGE

For Specified Performance −40 +125 °C

1

The mean of the gain drift distribution is typically −13 ppm/°C, with a σ = 3 ppm/°C.

2

The mean of the offset drift distribution is typically +5 μV/°C, with a σ = 3 μV/°C.

3

When the input common-mode voltage is less than 5 V, the supply current increases, which can be calculated by IS = −0.275 (VCM) + 2.5.

OPR

1

OPR

OPR

2

OPR

Rev. 0 | Page 3 of 16

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ABSOLUTE MAXIMUM RATINGS

Table 2.

Parameter Rating

Supply Voltage 12.5 V
Continuous Input Voltage −3 V to +68 V
Reverse Supply Voltage −0.3 V
HBM (Human Body Model) ESD Rating ±4000 V
CDM (Charged Device Model) ESD Rating ±1000 V
Operating Temperature Range −40°C to +125°C
Storage Temperature Range −65°C to +150°C
Output Short-Circuit Duration Indefinite

tresses above those listed under Absolute Maximum Ratings

S
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.

ESD CAUTION

Rev. 0 | Page 4 of 16

AD8211

G

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PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

OUT

1

AD8211

ND

2

1 2 5

1 2 5

V

TOP VIEW

(Not to Scale)

3

IN+

NC = NO CONNECT

Figure 3. Pin Configuration

3 4

3 4

6824-030

Figure 2. Metallization Diagram

V+

5

V

4

IN–

6824-002

Table 3. Pin Function Descriptions

Pin No. Mnemonic X Y Description

1 OUT −277 +466 Buffered Output.
2 GND −140 +466 Ground.
3 V
4 V

IN+

IN−

−228 −519 Noninverting Input.
+229 −519 Inverting Input.

5 V+ +264 +466 Supply.

Rev. 0 | Page 5 of 16