AD8219 [ADI]
Zero Drift, Unidirectional Current Shunt Monitor; 零漂移，单向电流分流监控器
| 型号： | AD8219 |
| 厂家： | 
ADI |
| 描述： | Zero Drift, Unidirectional Current Shunt Monitor |
| 文件： | 总16页 (文件大小：282K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
Zero Drift, Unidirectional
Current Shunt Monitor
AD8219
FUNCTIONAL BLOCK DIAGRAM
FEATURES
V
S
High common-mode voltage range
4 V to 80 V operating
R4
−0.3 V to +85 V survival
Buffered output voltage
Gain = 60 V/V
Wide operating temperature range: −40°C to +125°C
Excellent ac and dc performance
100 nV/°C typical offset drift
50 µV/°C typical offset
LDO
R1
R2
–IN
+IN
OUT
R3
AD8219
GND
Figure 1.
5 ppm/°C typical gain drift
110 dB typical CMRR at dc
APPLICATIONS
High-side current sensing
48 V telecom
Power management
Base stations
Unidirectional motor control
Precision high voltage current sources
GENERAL DESCRIPTION
The AD8219 is a high voltage, high resolution, current shunt
amplifier. It features a set gain of 60 V/V, with a maximum
0.3% gain error over the entire temperature range. The
buffered output voltage directly interfaces with any typical
converter. The AD8219 offers excellent input common-mode
rejection from 4 V to 80 V. The AD8219 performs unidirectional
current measurements across a shunt resistor in a variety of
industrial and telecom applications including motor control,
power management, and base station power amplifier bias
control.
The AD8219 offers breakthrough performance throughout
the −40°C to +125°C temperature range. It features a zero
drift core, which leads to a typical offset drift of 100 nV/°C
throughout the operating temperature and common-mode
voltage range. Special attention is devoted to output linearity
being maintained throughout the input differential voltage range,
regardless of the common-mode voltage present, while the
typical input offset voltage is 50 µ V.
The AD8219 is offered in a 8-lead MSOP package.
Rev. 0
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
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registeredtrademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
Fax: 781.461.3113
www.analog.com
©2011 Analog Devices, Inc. All rights reserved.
AD8219
TABLE OF CONTENTS
Features .............................................................................................. 1
Amplifier Core............................................................................ 10
Supply Connections ................................................................... 10
Output Clamping ....................................................................... 10
Application Information................................................................ 11
Output Linearity......................................................................... 11
Applications Information.............................................................. 12
High-Side Current Sensing....................................................... 12
Motor Control Current Sensing ............................................... 12
Outline Dimensions....................................................................... 13
Ordering Guide .......................................................................... 13
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
Theory of Operation ...................................................................... 10
REVISION HISTORY
1/11—Revision 0: Initial Version
Rev. 0 | Page 2 of 16
AD8219
SPECIFICATIONS
TOPR = −40°C to +125°C, TA = 25°C, RL = 25 kΩ, input common-mode voltage (VCM) = 4 V (RL is the output load resistor), unless
otherwise noted.
Table 1.
Parameter
Min
Typ
Max
Unit
Test Conditions/Comments
GAIN
Initial
Accuracy
60
±0.1
V/V
%
VO ≥ 0.1 V dc, TA
Accuracy over Temperature
Gain vs. Temperature
±0.3
%
TOPR
TOPR
±±
ppm/°C
VOLTAGE OFFSET
Offset Voltage (RTI1)
Over Temperature (RTI1)
Offset Drift
±200
±300
µV
µV
nV/°C
2±°C
TOPR
TOPR
±100
130
INPUT
Bias Current2
µA
µA
V
mV
dB
TA, input common mode = 4 V, VS = 4 V
TOPR
Common-mode continuous
Differential input voltage
TOPR
220
80
83
Common-Mode Input Voltage Range
Differential Input Voltage Range3
Common-Mode Rejection (CMRR)
4
0
94
110
OUTPUT
Output Voltage Range Low4
Output Voltage Range High4
Output Impedance
0.01
V
V
Ω
TA
TA
VS − 0.1
2
DYNAMIC RESPONSE
Small Signal −3 dB Bandwidth
Slew Rate
±00
1
kHz
V/µs
NOISE
0.1 Hz to 10 Hz, (RTI1)
Spectral Density, 1 kHz, (RTI1)
POWER SUPPLY
2.3
110
µV p-p
nV/√Hz
VS input range
TOPR
Operating Range
4
80
800
V
µA
dB
Quiescent Current Over Temperature±
Power Supply Rejection Ratio (PSRR)
TEMPERATURE RANGE
For Specified Performance
100
−40
110
+12±
°C
1 RTI = referred to input.
2 Refer to Figure 8 for further information on the input bias current. This current varies based on the input common-mode voltage. Additionally, the input bias current
flowing to the +IN pin is also the supply current to the internal LDO.
3 The differential input voltage is specified as 83 mV maximum because the output is internally clamped to ±.6 V. See the Output Clamping section.
4 See Figure 19 and Figure 20 for further information on the output range of the AD8219 with various loads. The AD8219 output clamps to a maximum voltage of ±.6 V
when the voltage at Pin +IN is greater than ±.6 V. When the voltage at +IN is less than ±.6 V, the output reaches a maximum value of (VS − 100 mV).
± VS (Pin 2) can be connected to a separate supply ranging from 4 V to 80 V, or it can be connected to the positive input pin (+IN) of the AD8219. In this mode, the
current drawn varies with increasing voltage. See Figure 9.
Rev. 0 | Page 3 of 16
AD8219
ABSOLUTE MAXIMUM RATINGS
Table 2.
Parameter
Stresses above those listed under Absolute Maximum Ratings
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.
Rating
Maximum Input Voltage ( +IN, −IN to GND)
Differential Input Voltage (+IN to –IN)
Human Body Model (HBM) ESD Rating
Operating Temperature Range (TOPR
Storage Temperature Range
−0.3 V to +8± V
±± V
±1000 V
−40°C to +12±°C
−6±°C to +1±0°C
Indefinite
)
Output Short-Circuit Duration
ESD CAUTION
Rev. 0 | Page 4 of 16
AD8219
PIN CONFIGURATION AND FUNCTION DESCRIPTIONS
+IN
1
2
3
4
8
7
6
5
–IN
NC
AD8219
TOP VIEW
(Not to Scale)
V
S
NC
NC
GND
OUT
NC = NO CONNECT.
DO NOT CONNECT TO THIS PIN.
Figure 2. Pin Configuration
Table 3. Pin Function Descriptions
Pin No.
Mnemonic
Description
1
2
3
4
±
6
7
8
+IN
VS
NC
GND
OUT
NC
NC
−IN
Noninverting Input.
Supply Pin. Bypass with a standard 0.1 μF capacitor.
Do Not Connect to This Pin.
Ground.
Output.
Do Not Connect to This Pin.
Do Not Connect to This Pin.
Inverting Input.
Rev. 0 | Page ± of 16
AD8219
TYPICAL PERFORMANCE CHARACTERISTICS
40
30
–19.0
–19.5
–20.0
–20.5
–21.0
–21.5
–22.0
–22.5
–23.0
–23.5
–24.0
20
10
0
–10
–20
–30
–40
–40
–20
0
20
40
60
80
100
120
140
1k
10k
100k
1M
10M
TEMPERATURE (°C)
FREQUENCY (Hz)
Figure 3. Typical Input Offset vs. Temperature
Figure 6. Typical Small Signal Bandwidth (VOUT = 200 mV p-p)
120
7
6
110
100
90
5
4
3
2
80
1
70
0
60
–1
–2
50
100
1k
10k
100k
1M
0
1
2
3
4
5
6
7
8
9
10
FREQUENCY (Hz)
DIFFERENTIAL INPUT VOLTAGE (mV)
Figure 4. Typical CMRR vs. Frequency
Figure 7. Typical Output Error vs. Differential Input Voltage
300
0
–50
250
200
150
100
50
–100
–150
–200
–250
–300
–350
–400
–450
–500
+IN
–IN
0
–40
–20
0
20
40
60
80
100
120
140
0
5
10 15 20 25 30 35 40 45 50 55 60 65 70 75 80
INPUT COMMON-MODE VOLTAGE (V)
TEMPERATURE (°C)
Figure 5. Typical Gain Error vs. Temperature
Figure 8. Input Bias Current vs. Input Common-Mode Voltage
(Differential Input Voltage = 5 mV) (VS = 5 V)
Rev. 0 | Page 6 of 16
AD8219
550
500
450
400
350
300
V
= 5V
CM
INPUT
50mV/DIV
V
= 80V
CM
OUTPUT
2V/DIV
0
5
10 15 20 25 30 35 40 45 50 55 60 65 70 75 80
SUPPLY VOLTAGE (V)
5µs/DIV
Figure 9. Typical Supply Current vs. Supply Voltage (VS Connected to +IN)
Figure 12. Rise Time (Differential Input = 50 mV)
550
500
450
400
350
300
250
200
INPUT
5mV/DIV
OUTPUT
200mV/DIV
–40
–20
0
20
40
60
80
100
120
140
TEMPERATURE (°C)
1µs/DIV
Figure 13. Fall Time (Differential Input = 5 mV)
Figure 10. Typical Supply Current Change over Temperature (VS = 5 V)
INPUT
50mV/DIV
INPUT
5mV/DIV
OUTPUT
2V/DIV
OUTPUT
200mV/DIV
5µs/DIV
1µs/DIV
Figure 14. Fall Time (Differential Input = 50 mV)
Figure 11. Rise Time (Differential Input = 5 mV)
Rev. 0 | Page 7 of 16
AD8219
7.0
6.5
6.0
5.5
5.0
4.5
4.0
INPUT
100mV/DIV
OUTPUT
2V/DIV
–40
–20
0
20
40
60
80
100
120
5µs/DIV
TEMPERATURE (°C)
Figure 15. Differential Overload Recovery, Falling
Figure 18. Maximum Output Source Current vs. Temperature
5.0
+125°C
+25°C
–40°C
4.8
4.5
4.3
4.0
3.8
3.5
3.3
3.0
INPUT
100mV/DIV
OUTPUT
2V/DIV
0
0.5
1.0
1.5
2.0
2.5
3.0
5µs/DIV
SOURCE CURRENT (mA)
Figure 16. Differential Overload Recovery, Rising
Figure 19. Output Voltage Range vs. Output Source Current (VS = 5 V)
12
11
10
9
0.40
+125°C
+25°C
–40°C
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0
8
7
6
5
–40
–20
0
20
40
60
80
100
120
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
TEMPERATURE (°C)
SINK CURRENT (mA)
Figure 17. Maximum Output Sink Current vs. Temperature
Figure 20. Output Voltage Range From Ground vs. Output Sink Current (VS = 5 V)
Rev. 0 | Page 8 of 16
AD8219
70
60
50
40
30
20
10
0
INPUT COMMON MODE
50V/DIV
OUTPUT
200mV/DIV
–6
–4
–2
0
2
4
6
GAIN DRIFT (ppm/°C)
2µs/DIV
Figure 24. Gain Drift Distribution
Figure 21. Common-Mode Step Response (Falling)
35
30
25
20
15
10
5
INPUT COMMON MODE
50V/DIV
OUTPUT
200mV/DIV
0
–0.6
–0.4
–0.2
0
0.2
0.4
0.6
OFFSET DRIFT (µV/°C)
1µs/DIV
Figure 25. Input Offset Drift Distribution
Figure 22. Common-Mode Step Response (Rising)
50
40
30
20
10
0
–150
–100
–50
0
50
100
150
V
(µV)
OSI
Figure 23. Input Offset Distribution
Rev. 0 | Page 9 of 16
AD8219
THEORY OF OPERATION
The AD8219 accurately amplifies the input differential signal,
rejecting high voltage common modes ranging from 4 V to 80 V.
AMPLIFIER CORE
In typical applications, the AD8219 amplifies a small differential
input voltage generated by the load current flowing through
a shunt resistor. The AD8219 rejects high common-mode vol-
tages (up to 80 V) and provides a ground referenced, buffered
output that interfaces with an analog-to-digital converter (ADC).
Figure 26 shows a simplified schematic of the AD8219.
The main amplifier uses a novel zero drift architecture, providing
the end user with breakthrough temperature stability. The offset
drift is typically less than 100 nV/°C. This performance leads
to optimal accuracy and dynamic range.
SUPPLY CONNECTIONS
The AD8219 includes an internal LDO, which allows the user
to connect the VS pin to the inputs, or use a separate supply at
Pin 2 (VS) to power the device. The input range of the supply
pin is equivalent to the input common-mode range of 4 V to
80 V. The user must ensure that VS is always connected to the
+IN pin or a separate low impedance supply, which can range
from 4 V to 80 V. The VS pin should not be floating.
4V TO 80V
GND
R4
V
S
I
LOAD
V
LDO
R1
R2
–IN
+IN
2
1
SHUNT
OUT
LOAD
V
4V
TO
80V
R3
AD8219
OUTPUT CLAMPING
GND
When the input common-mode voltage in the application is
above 5.6 V, the internal LDO output of the AD8219 also
reaches its maximum value of 5.6 V, which is the maximum
output range of the AD8219. Because in typical applications
the output interfaces with a converter, clamping the AD8219
output voltage to 5.6 V ensures the ADC input is not damaged
due to excessive overvoltage.
Figure 26. Simplified Schematic
The AD8219 is configured as a difference amplifier. The
transfer function is
OUT = (R4/R1) × (V1 − V2)
Resistors R4 and R1 are matched to within 0.01% and have
values of 1.5 MΩ and 25 kΩ, respectively, meaning an input
to output total gain of 60 V/V for the AD8219, while the
difference at V1 and V2 is the voltage across the shunt resistor
or VIN. Therefore, the input-to-output transfer function for the
AD8219 is
OUT = (20) × (VIN)
Rev. 0 | Page 10 of 16
AD8219
APPLICATION INFORMATION
Regardless of the common mode, the AD8219 provides a
OUTPUT LINEARITY
correct output voltage when the input differential is at least
1 mV. The ability of the AD8219 to work with very small
differential inputs, regardless of the common-mode voltage,
allows for optimal dynamic range, accuracy, and flexibility in
any current sensing application.
In all current sensing applications where the common-mode
voltage can vary significantly, it is important that the current
sensor maintain the specified output linearity, regardless of
the input differential or common-mode voltage. The AD8219
maintains a very high input-to-output linearity even when the
differential input voltage is very small.
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0
1
2
3
4
5
6
7
8
9
10
DIFFERENTIAL INPUT VOLTAGE (mV)
Figure 27. Typical Gain Linearity at Small Differential Inputs
(VCM = 4 V to 80 V)
Rev. 0 | Page 11 of 16
AD8219
APPLICATIONS INFORMATION
HIGH-SIDE CURRENT SENSING
MOTOR CONTROL CURRENT SENSING
In this configuration, the shunt resistor is referenced to the
battery (see Figure 28). High voltage is present at the inputs
of the current sense amplifier. When the shunt is battery
referenced, the AD8219 produces a linear ground referenced
analog output.
The AD8219 is a practical, accurate solution for high-side
current sensing in motor control applications. In cases where
the shunt resistor is referenced to a battery and the current
flowing is unidirectional (as shown in Figure 30), the AD8219
monitors the current with no additional supply pin necessary
provided the battery voltage in the following circuit is in the 4 V
to 80 V range.
I
LOAD
4V
TO
BATTERY
SHUNT
LOAD
80V
I
MOTOR
–IN
+IN
AD8219
MOTOR
–IN
+IN
V
OUT
S
GND
AD8219
V
OUT
S
GND
Figure 28. Battery Referenced Shunt Resistor
Figure 28 shows the supply pin, VS, connected directly to the
positive input (+IN) pin. In this mode, the internal LDO powers
the AD8219 as long as the common-mode voltage at the input
pins is 4 V to 80 V. Additionally, VS can also be connected to a
standalone supply that can vary from 4 V to 80 V as shown in
Figure 29.
Figure 30. High-Side Current Sensing in Motor Control
I
LOAD
4V
TO
80V
SHUNT
LOAD
–IN
+IN
AD8219
V
OUT
S
4V
TO
80V
GND
Figure 29. Standalone Supply Operation
Rev. 0 | Page 12 of 16
AD8219
OUTLINE DIMENSIONS
3.20
3.00
2.80
8
1
5
4
5.15
4.90
4.65
3.20
3.00
2.80
PIN 1
IDENTIFIER
0.65 BSC
0.95
0.85
0.75
15° MAX
1.10 MAX
0.80
0.55
0.40
0.15
0.05
0.23
0.09
6°
0°
0.40
0.25
COPLANARITY
0.10
COMPLIANT TO JEDEC STANDARDS MO-187-AA
Figure 31. 8-Lead Mini Small Outline Package [MSOP]
(RM-8)
Dimensions shown in millimeters
ORDERING GUIDE
Model1
Temperature Range
Package Description
Package Option
RM-8
RM-8
Branding
Y3S
Y3S
AD8219BRMZ
AD8219BRMZ-RL
−40°C to +12±°C
−40°C to +12±°C
8-Lead Mini Small Outline Package [MSOP]
8-Lead Mini Small Outline Package [MSOP]
1 Z = RoHS Compliant Part.
Rev. 0 | Page 13 of 16
AD8219
NOTES
Rev. 0 | Page 14 of 16
AD8219
NOTES
Rev. 0 | Page 1± of 16
AD8219
NOTES
©2011 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D09415-0-1/11(0)
Rev. 0 | Page 16 of 16
相关型号：
©2020 ICPDF网 联系我们和版权申明