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INA827
SBOS631B – JUNE 2012 – REVISED NOVEMBER 2017
INA827 Wide Supply Range, Rail-to-Rail Output
Instrumentation Amplifier With a Minimum Gain of 5
1 Features
3 Description
•
The INA827 is a low-cost instrumentation amplifier
(INA) that offers extremely low power consumption
and operates over a very wide single- or dual-supply
range. The device is optimized for the lowest possible
gain drift of only 1 ppm per degree Celsius in G = 5,
which requires no external resistor. However, a single
external resistor sets any gain from 5 to 1000.
1
•
•
•
•
•
•
•
•
•
Eliminates Errors from External Resistors at Gain
of 5
Common-Mode Range Goes Below
Negative Supply
Input Protection: Up to ±40 V
Rail-to-Rail Output
Outstanding Precision:
– Common-Mode Rejection: 88 dB, minimum
– Low Offset Voltage: 150 µV, maximum
– Low Drift: 2.5 µV/°C, maximum
– Low Gain Drift: 1 ppm/°C, max (G = 5 V/V)
– Power-Supply Rejection:
100 dB, min (G = 5)
– Noise: 17 nV/√Hz, G = 1000 V/V
High Bandwidth:
– G = 5: 600 kHz
– G = 100: 150 kHz
Supply Current: 200 µA, typical
Supply Range:
– Single Supply: 3 V to 36 V
– Dual Supply: ±1.5 V to ±18 V
Specified Temperature Range:
–40°C to +125°C
Package: 8-pin VSSOP
The INA827 is optimized to provide excellent
common-mode rejection ratio (CMRR) of over 88 dB
(G = 5) over frequencies up to 5 kHz. In G = 5,
CMRR exceeds 88 dB across the full input commonmode range from the negative supply all the way up
to 1 V of the positive supply. Using a rail-to-rail
output, the INA827 is well-suited for low-voltage
operation from a 3-V singlesupply as well as dual
supplies up to ±18 V. Additional circuitry protects the
inputs against overvoltage of up to ±40 V beyond the
power supplies by limiting the input currents to a save
level.
The INA827 is available in a small VSSOP-8 package
and is specified for the –40°C to +125°C temperature
range. For a similar instrumentation amplifier with a
gain range of 1 V/V to 1000 V/V, see the INA826.
Device Information(1)
PART NUMBER
Industrial Process Controls
Multichannel Systems
Power Automation
Weigh Scales
Medical Instrumentation
Data Acquisition
BODY SIZE (NOM)
VSSOP (8)
3.00 mm × 3.00 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
2 Applications
•
•
•
•
•
•
PACKAGE
INA827
Simplified Schematic
V+
0.1 mF
8
1
-IN
10 kW
50 kW
A1
VO = G ´ (VIN+ - VIN-)
2
8 kW
RG
G=5+
A3
8 kW
7
+
3
Load VO
10 kW
+IN
4
80 kW
RG
50 kW
A2
6
REF
TI Device
5
0.1 mF
VCopyright © 2016, Texas Instruments Incorporated
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
INA827
SBOS631B – JUNE 2012 – REVISED NOVEMBER 2017
www.ti.com
Table of Contents
1
2
3
4
5
6
7
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
4
6.1
6.2
6.3
6.4
6.5
6.6
4
4
4
4
5
7
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics...........................................
Typical Characteristics ..............................................
Detailed Description ............................................ 16
7.1 Overview ................................................................. 16
7.2 Functional Block Diagram ....................................... 16
7.3 Feature Description................................................. 17
7.4 Device Functional Modes........................................ 23
8
Application and Implementation ........................ 24
8.1 Application Information............................................ 24
8.2 Typical Application .................................................. 25
9 Power Supply Recommendations...................... 27
10 Layout................................................................... 27
10.1 Layout Guidelines ................................................. 27
10.2 Layout Example .................................................... 27
11 Device and Documentation Support ................. 28
11.1
11.2
11.3
11.4
11.5
11.6
Documentation Support ........................................
Receiving Notification of Documentation Updates
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
28
28
28
28
28
28
12 Mechanical, Packaging, and Orderable
Information ........................................................... 28
4 Revision History
Changes from Revision A (July 2013) to Revision B
Page
•
Added Device Information table, ESD Ratings table, Recommended Operating Conditions table, Overview section,
Functional Block Diagram section, Feature Description section, Device Functional Modes section, Application and
Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation
Support section, and Mechanical, Packaging, and Orderable Information section ............................................................... 1
•
Deleted device graphic from top of page 1 ............................................................................................................................ 1
•
Changed Features section: changed sub-bullets of Supply Range bullet ............................................................................. 1
•
Changed MSOP to VSSOP throughout document ................................................................................................................ 1
•
Changed single supply value in first paragraph of Description section ................................................................................. 1
•
Added Simplified Schematic title ............................................................................................................................................ 1
•
Deleted Package and Ordering Information table .................................................................................................................. 3
•
Changed Pin Configuration and Functionssection: changed section title, changed Pin Functions title, added I/O column .. 3
•
Changed test conditions of Input, PSRR and VCM parameters in Electrical Characteristics table ........................................ 5
•
Changed minimum specifications of Power Supply, VS parameter in Electrical Characteristics table .................................. 6
•
Changed Typical Characteristics section: moved conditions from title to conditions line under curve .................................. 7
•
Changed conditions of Figure 7 and Figure 8 ........................................................................................................................ 8
•
Changed conditions of Figure 37 and Figure 38 .................................................................................................................. 13
•
Changed power-supply range in Operating Voltage section ............................................................................................... 22
•
Changed power supply low level in Low-Voltage Operation section ................................................................................... 22
•
Added Design Requirements, Detailed Design Procedure, and Application Curves to the Typical Application section ..... 25
Changes from Original (June 2012) to Revision A
Page
•
Changed front-page graphic................................................................................................................................................... 1
•
Updated Figure 15.................................................................................................................................................................. 8
•
Updated Figure 16.................................................................................................................................................................. 8
•
Updated Figure 61................................................................................................................................................................ 24
2
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SBOS631B – JUNE 2012 – REVISED NOVEMBER 2017
5 Pin Configuration and Functions
DGK Package
8-Pin VSSOP
Top View
-IN
1
8
+VS
RG
2
7
VOUT
RG
3
6
REF
+IN
4
5
-VS
Pin Functions
NO.
I/O
–IN
NAME
1
I
Negative input
+IN
4
I
Positive input
REF
6
I
Reference input. This pin must be driven by low impedance.
RG
DESCRIPTION
2, 3
—
Gain setting pin. Place a gain resistor between pin 2 and pin 3.
VOUT
7
O
Output
–VS
5
—
Negative supply
+VS
8
—
Positive supply
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INA827
SBOS631B – JUNE 2012 – REVISED NOVEMBER 2017
www.ti.com
6 Specifications
6.1 Absolute Maximum Ratings (1)
Voltage
MIN
MAX
Supply
–20
20
Input
–40
40
–20
20
REF input
Output short-circuit
(2)
Temperature range
–55
V
150
Junction, TJ
175
Storage, Tstg
(2)
V
Continuous
Operating, TA
(1)
UNIT
–65
°C
150
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
Short-circuit to VS / 2.
6.2 ESD Ratings
VALUE
V(ESD)
(1)
(2)
Electrostatic discharge
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001 (1)
±2000
Charged-device model (CDM), per JEDEC specification JESD22-C101 (2)
±750
UNIT
V
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
Single supply
NOM
MAX
UNIT
3
36
±1.5
±18
Specified temperature
–40
125
°C
Operating temperature
–50
150
°C
Supply voltage
Dual supply
V
6.4 Thermal Information
INA827
THERMAL METRIC
(1)
DGK (VSSOP)
UNIT
8 PINS
RθJA
Junction-to-ambient thermal resistance
215.4
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
66.3
°C/W
RθJB
Junction-to-board thermal resistance
97.8
°C/W
ψJT
Junction-to-top characterization parameter
10.5
°C/W
ψJB
Junction-to-board characterization parameter
96.1
°C/W
RθJC(bot)
Junction-to-case (bottom) thermal resistance
N/A
°C/W
(1)
4
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
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SBOS631B – JUNE 2012 – REVISED NOVEMBER 2017
6.5 Electrical Characteristics
at TA = +25°C, VS = ±15 V, RL = 10 kΩ, VREF = 0 V, and G = 5 (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
RTI, VOS = VOSI + (VOSO / G)
40
150
µV
TA = –40°C to +125°C
0.5
2.5
µV/°C
RTI, VOS = VOSI + (VOSO / G)
500
2000
5
30
INPUT
VOSI
Input stage
Offset voltage (1)
VOSO
PSRR
ZIN
Output stage
Power-supply rejection ratio
Impedance
TA = –40°C to +125°C
G = 5, VS = ±1.5 V to ±18 V
100
120
G = 10, VS = ±1.5 V to ±18 V
106
126
G > 100, VS = ±1.5 V to ±18 V
120
140
Differential
25
VS = ±1.5 V to ±18 V, VO = 0 V
Operating input range (2)
Input overvoltage range
(V–) – 0.2
MHz
(V+) – 0.9
VS = ±1.5 V to ±18 V, VO = 0 V, TA = +125°C
(V–) – 0.05
(V+) – 0.8
VS = ±1.5 V to ±18 V, VO = 0 V, TA = –40°C
(V–) – 0.3
(V+) – 0.95
TA = –40°C to +125°C
(V+) – 40
G = 5, VCM = V– to (V+) – 1 V
DC to 60 Hz
CMRR
GΩ || pF
10 || 5
RFI filter, –3-dB frequency
VCM
dB
2 || 1
Common-mode
µV
µV/°C
Common-mode rejection ratio
(V–) + 40
88
100
G = 10, VCM = V– to (V+) – 1 V
94
106
G > 100, VCM = V– to (V+) – 1 V
110
126
G = 5, VCM = V– to (V+) – 1 V
At 5 kHz
V
V
dB
88
G = 10, VCM = V– to (V+) – 1 V
94
G > 100, VCM = V– to (V+) – 1 V
104
BIAS CURRENT
IB
Input bias current
IOS
Input offset current
35
TA = –40°C to +125°C
50
nA
95
–5
0.7
TA = –40°C to +125°C
5
nA
10
NOISE VOLTAGE (3)
eNI
Voltage noise
eNO
RTI
Referred-to-input
iN
Noise current
Input
f = 1 kHz, G = 1000, RS = 0 Ω
17
18
Output
f = 1 kHz, G = 5, RS = 0 Ω
250
285
G = 5, fB = 0.1 Hz to 10 Hz, RS = 0 Ω
1.4
G = 1000, fB = 0.1 Hz to 10 Hz, RS = 0 Ω
0.5
f = 1 kHz
120
fB = 0.1 Hz to 10 Hz
nV/√Hz
µVPP
fA/√Hz
5
pAPP
GAIN
80 kW
G
Gain equation
G
Range of gain
GE
5+
5
G = 5, VO = ±10 V
Gain error
G = 10 to 1000, VO = ±10 V
Gain versus temperature (4)
1000
±0.005%
±0.035%
±0.1%
±0.4%
G = 5, TA = –40°C to +125°C
±0.1
±1
G > 5, TA = –40°C to +125°C
8
25
G = 5 to 100, VO = –10 V to +10 V, RL = 10 kΩ
Gain nonlinearity
(1)
(2)
V/V
RG
G = 1000, VO = –10 V to +10 V, RL = 10 kΩ
2
5
20
50
V/V
ppm/°C
ppm
Total offset, referred-to-input (RTI): VOS = VOSI + (VOSO / G).
Input voltage range of the INA827 input stage. The input range depends on the common-mode voltage, differential voltage, gain, and
reference voltage. See the Typical Characteristics section for more information.
(3)
(eNI)2 +
(4)
eNO
2
G
Total RTI voltage noise =
.
The values specified for G > 5 do not include the effects of the external gain-setting resistor, RG.
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SBOS631B – JUNE 2012 – REVISED NOVEMBER 2017
www.ti.com
Electrical Characteristics (continued)
at TA = +25°C, VS = ±15 V, RL = 10 kΩ, VREF = 0 V, and G = 5 (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
OUTPUT
Voltage swing
RL = 10 kΩ
(V–) + 0.1
Load capacitance stability
Short-circuit current
(V+) – 0.15
V
1000
pF
Continuous to common
±16
mA
G=5
600
G = 10
530
G = 100
150
FREQUENCY RESPONSE
BW
SR
Bandwidth, –3 dB
Slew rate
To 0.01%
tS
Settling time
To 0.001%
G = 1000
15
G = 5, VO = ±14.5 V
1.5
G = 100, VO = ±14.5 V
1.5
G = 5, VSTEP = 10 V
10
G = 100, VSTEP = 10 V
12
G = 1000, VSTEP = 10 V
95
G = 1, VSTEP = 10 V
11
G = 100, VSTEP = 10 V
18
G = 1000, VSTEP = 10 V
118
kHz
V/µs
µs
REFERENCE INPUT
RIN
Input impedance
60
Voltage range
V–
Gain to output
kΩ
V+
1
Reference gain error
V
V/V
0.01
%
POWER SUPPLY
VS
Power-supply voltage
IQ
Quiescent current
Single
Dual
3.0
36
±1.5
±18
VIN = 0 V
200
250
TA = –40°C to +125°C
250
320
V
µA
TEMPERATURE RANGE
θJA
6
Specified
–40
125
Operating
–50
150
Thermal resistance
215
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°C
°C
°C/W
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SBOS631B – JUNE 2012 – REVISED NOVEMBER 2017
6.6 Typical Characteristics
at TA = +25°C, VS = ±15 V, RL = 10 kΩ, VREF = 0 V, and G = 5 (unless otherwise noted)
250
30
SD: 40.1 µV
MEAN: −7.6 µV
SD: 0.51 µV/°C
MEAN: 0.08 µV/°C
25
200
20
Units
Units
150
15
100
10
50
5
VOSI (µV)
3
2
1
0
−1
−2
−3
150
130
90
110
70
50
30
10
−10
−30
−50
−70
−90
−110
−130
0
−150
0
VOSI Drift (µV/°C )
G001
Figure 1. Typical Distribution of Input Offset Voltage
G002
Figure 2. Typical Distribution of Input Offset Voltage Drift
200
16
160
SD: 5.3 µV/°C
MEAN: −7.7 µV/°C
12
Units
Units
120
8
80
4
40
VOSO (µV)
25
20
15
10
5
0
VOSO Drift (µV/°C )
G002
Figure 3. Typical Distribution of Output Offset Voltage
−5
−10
−15
−25
−20
0
−2000
−1800
−1600
−1400
−1200
−1000
−800
−600
−400
−200
0
200
400
600
800
1000
1200
1400
1600
1800
2000
0
G004
Figure 4. Typical Distribution of Output Offset Voltage Drift
700
500
SD: 0.59 nA
MEAN: 0.01 nA
600
400
300
400
Units
Units
500
300
200
200
100
100
IB (nA)
4
3.5
3
2.5
2
1.5
1
0.5
0
−0.5
−1
−1.5
−2
−2.5
−3
−4
IOS (nA)
G005
Figure 5. Typical Distribution of Input Bias Current
−3.5
50
48
46
44
42
40
38
36
34
32
30
28
26
24
22
0
20
0
G006
Figure 6. Typical Distribution of Input Offset Current
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Typical Characteristics (continued)
at TA = +25°C, VS = ±15 V, RL = 10 kΩ, VREF = 0 V, and G = 5 (unless otherwise noted)
Single supply, VS = +3 V, G = 5
Single supply, VS = +3 V, G = 100
Figure 7. Input Common-Mode Voltage vs Output Voltage
Figure 8. Input Common-Mode Voltage vs Output Voltage
4.5
Common−Mode Voltage (V)
Common−Mode Voltage (V)
4.5
3.5
2.5
Vref = 0V
Vref = 2.5V
1.5
0.5
−0.5
−0.5
0.5
1.5
2.5
3.5
Output Voltage (V)
4.5
3.5
2.5
1.5
0.5
−0.5
−0.5
5.5
4.5
5.5
G009
Figure 10. Input Common-Mode Voltage vs Output Voltage
6
16
4
2
Common−Mode Voltage (V)
Common−Mode Voltage (V)
1.5
2.5
3.5
Output Voltage (V)
Single supply, VS = +5 V, G = 100
Figure 9. Input Common-Mode Voltage vs Output Voltage
Gain = 5
Gain = 100
0
−2
−4
12
8
Vs = +/− 12V
Vs = +/− 15V
4
0
−4
−8
−12
−6
−4
−2
0
2
Output Voltage (V)
4
6
−16
−16
G011
Dual supply, VS = ±5 V
−12
−8
−4
0
4
Output Voltage (V)
8
12
16
G012
Dual supply, VS = ±15 V, ±12 V, G = 5
Figure 11. Input Common-Mode Voltage vs Output Voltage
8
0.5
G009
Single supply, VS = +5 V, G = 5
−6
Vref = 0V
Vref = 2.5V
Figure 12. Input Common-Mode Voltage vs Output Voltage
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Typical Characteristics (continued)
8
16
12
6
12
4
8
2
4
0
0
8
Vs = +/− 12V
Vs = +/− 15V
4
0
−4
−4
−12
−6
−16
−16
−12
−8
−4
0
4
Output Voltage (V)
8
12
16
−4
−2
−8
IIN
VOUT
−8
−12
−8
−30
−20
G013
−10
0
10
Input Voltage (V)
20
30
−16
G014
G = 1, VS = ±15 V
Dual supply, VS = ±15 V, ±12 V, G = 100
Figure 14. Input Overvoltage vs Input Current
Figure 13. Input Common-Mode Voltage vs Output Voltage
140
Common-Mode Rejection Ratio (dB)
160
Common-Mode Rejection Ratio (dB)
Output Voltage (V)
16
Input Current (mA)
Common−Mode Voltage (V)
at TA = +25°C, VS = ±15 V, RL = 10 kΩ, VREF = 0 V, and G = 5 (unless otherwise noted)
140
120
100
80
60
40
G=5
G = 10
G = 100
G = 1000
20
0
10
100
120
100
80
60
G=5
40
G = 10
20
G = 100
G = 1000
0
1k
10k
10
100k
Frequency (Hz)
100
1k
10k
Frequency (Hz)
C015
100k
C016
1-kΩ source imbalance
Figure 16. CMRR vs Frequency (RTI)
180
160
160
140
140
120
120
PSRR (dB)
PSRR (dB)
Figure 15. CMRR vs Frequency (RTI)
180
100
80
60
80
60
G=5
G = 10
G = 100
G = 1000
40
20
0
100
10
100
G=5
G = 10
G = 100
G = 1000
40
20
1k
Frequency (Hz)
10k
100k
0
10
G018
Figure 17. Positive PSRR vs Frequency (RTI)
100
1k
Frequency (Hz)
10k
100k
G019
Figure 18. Negative PSRR vs Frequency (RTI)
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Typical Characteristics (continued)
at TA = +25°C, VS = ±15 V, RL = 10 kΩ, VREF = 0 V, and G = 5 (unless otherwise noted)
70
10k
50
Gain (dB)
40
Noise Density (nV/ Hz)
G=5
G = 10
G = 100
G = 1000
60
30
20
10
0
−10
G=5
G = 10
G = 100
G = 1000
1k
100
10
−20
−30
100
1k
10k
100k
Frequency (Hz)
1M
1
100m
10M
G022
Figure 19. Gain vs Frequency
1
10
100
1k
Frequency (Hz)
10k
100k
G023
Figure 20. Voltage Noise Spectral Density vs Frequency
(RTI)
400
Noise (1 mV/div)
Current Noise Density (fA/ Hz)
500
300
200
100
0
1
10
100
Frequency (Hz)
1k
10k
Time (1 s/div)
G025
G024
Figure 22. 0.1-Hz to 10-Hz RTI Voltage Noise (G = 5)
Noise (2 pA/div)
Noise (500 nV/div)
Figure 21. Current Noise Spectral Density vs Frequency
(RTI)
Time (1 s/div)
Time (1 s/div)
G026
Figure 23. 0.1-Hz to 10-Hz RTI Voltage Noise (G = 1000)
10
G027
Figure 24. 0.1-Hz to 10-Hz RTI Current Noise
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Typical Characteristics (continued)
at TA = +25°C, VS = ±15 V, RL = 10 kΩ, VREF = 0 V, and G = 5 (unless otherwise noted)
100
−45°C
25°C
85°C
125°C
120
−45°C
25°C
85°C
125°C
90
80
Input Bias Current (nA)
Input Bias Current (nA)
140
100
80
60
40
70
60
50
40
30
20
20
10
0
−0.5
0.0
0.5
1.0
1.5
Common−Mode Voltage (V)
2.0
0
−18
2.5
−14
−10
G028
VS = +2.7 V
14
18
G029
VS = ±15 V
Figure 25. Input Bias Current vs Common-Mode Voltage
Figure 26. Input Bias Current vs Common-Mode Voltage
100
2.5
Unit 1
Unit 2
Unit 3
80
Unit 1
Unit 2
2
Input Offset Current (nA)
Input Bias Current (nA)
−6
−2
2
6
10
Common−Mode Voltage (V)
60
40
20
1.5
1
0.5
0
−0.5
0
−50
−25
0
25
50
75
Temperature (°C)
100
125
−1
−50
150
Figure 27. Input Bias Current vs Temperature
0
25
50
75
Temperature (°C)
100
125
150
G031
Figure 28. Input Offset Current vs Temperature
50
300
30
Quiescent Current (µA)
Unit 1
Unit 2
Unit 3
40
Gain Error (ppm)
−25
G030
20
10
0
−10
−20
−30
250
Unit 1
Unit 2
Unit 3
200
150
−40
−50
−50
−25
0
25
50
75
Temperature (°C)
100
125
150
100
−50
G032
Figure 29. Gain Error vs Temperature (G = 5)
−25
0
25
50
75
Temperature (°C)
100
125
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G034
Figure 30. Supply Current vs Temperature
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Typical Characteristics (continued)
10
10
8
8
6
6
Non−Linearity (ppm)
Non−Linearity (ppm)
at TA = +25°C, VS = ±15 V, RL = 10 kΩ, VREF = 0 V, and G = 5 (unless otherwise noted)
4
2
0
−2
−4
4
2
0
−2
−4
−6
−6
−8
−8
−10
−10
−8
−6
−4
−2
0
2
4
Output Voltage (V)
6
8
−10
−10
10
−8
8
40
6
30
4
2
0
−2
−4
6
8
−8
−6
G037
Figure 33. Gain Nonlinearity (G = 100)
−4
−2
0
2
4
Output Voltage (V)
6
8
10
G038
Figure 34. Gain Nonlinearity (G = 1000)
100
VS = ±15 V
−45°C
25°C
85°C
125°C
40
80
20
0
−20
−40
−45°C
25°C
85°C
125°C
40
20
0
−20
−40
−60
−60
−80
−15.5
VS = ±15 V
60
Offset Voltage (µV)
60
Offset Voltage (µV)
G036
−20
−50
−10
10
80
−80
−15
Common−Mode Voltage (V)
−14.5
−100
13.5
G057
VS = ±15 V
14
Common−Mode Voltage (V)
14.5
G058
VS = ±15 V
Figure 35. Offset Voltage vs
Negative Common-Mode Voltage
12
10
0
−40
−2
0
2
4
Output Voltage (V)
8
−10
−30
−4
6
10
−8
−6
−2
0
2
4
Output Voltage (V)
20
−6
−8
−4
Figure 32. Gain Nonlinearity (G = 10)
50
Non−Linearity (ppm)
Non−Linearity (ppm)
Figure 31. Gain Nonlinearity (G = 5)
10
−10
−10
−6
G035
Figure 36. Offset Voltage vs
Positive Common-Mode Voltage
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Typical Characteristics (continued)
at TA = +25°C, VS = ±15 V, RL = 10 kΩ, VREF = 0 V, and G = 5 (unless otherwise noted)
VS = +3 V
VS = +3 V
Figure 37. Offset Voltage vs
Negative Common-Mode Voltage
Figure 38. Offset Voltage vs
Positive Common-Mode Voltage
15
−14
−45°C
25°C
85°C
125°C
Output Voltage (V)
14.8
14.7
−14.2
14.6
14.5
14.4
14.3
−14.3
−14.4
−14.5
−14.6
−14.7
14.2
−14.8
14.1
−14.9
14
0
1
2
3
4
5
6
7
Output Current (mA)
8
9
−45°C
25°C
85°C
125°C
−14.1
Output Voltage (V)
14.9
−15
10
0
1
2
3
G039
VS = ±15 V
4
5
6
7
Output Current (mA)
8
9
10
G040
VS = ±15 V
Figure 39. Positive Output Voltage Swing vs
Output Current
Figure 40. Negative Output Voltage Swing vs
Output Current
35
20
Vs = ±15V
Vs = ±2.5V
30
Settle to 0.01%
Settle to 0.001%
18
Settling Time (µs)
Output Voltage (Vpp)
16
25
20
15
10
14
12
10
8
6
4
5
0
2
1k
10k
100k
Frequency (Hz)
1M
0
2
G043
4
6
8
10
12
14
Step Size (V)
16
18
20
G044
VS = ±15 V
Figure 41. Large-Signal Frequency Response
Figure 42. Settling Time vs Step Size
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Typical Characteristics (continued)
at TA = +25°C, VS = ±15 V, RL = 10 kΩ, VREF = 0 V, and G = 5 (unless otherwise noted)
Output Voltage (10 mV/div)
Output Voltage (V)
0.2
0.1
CL = 0 pF
CL = 100 pF
CL = 220 pF
CL = 500 pF
CL = 1 nF
CL = 220 nF
0
−0.1
−0.2
Time (5 ms/div)
Time (5 ms/div)
G045
G046
G = 5, RL = 1 kΩ, CL = 100 pF
Figure 44. Small-Signal Response
Output Voltage (10 mV/div)
Output Voltage (10 mV/div)
Figure 43. Small-Signal Response Over Capacitive Loads
(G = 5)
Time (5 ms/div)
Time (20 ms/div)
G052
G = 10, RL = 10 kΩ, CL = 100 pF
Figure 46. Small-Signal Response
Output Voltage (5 V/div)
Output Voltage (10 mV/div)
Output Voltage
Output Settling
Time (100 ms/div)
Time (50 ms/div)
G054
G = 1000, RL = 10 kΩ, CL = 100 pF
Output Settling (0.002%/div)
Figure 45. Small-Signal Response
G061
G = 5, RL = 10 kΩ, CL = 100 pF
Figure 47. Small-Signal Response
14
G053
G = 100, RL = 10 kΩ, CL = 100 pF
Figure 48. Large-Signal Response and Settling Time
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Typical Characteristics (continued)
at TA = +25°C, VS = ±15 V, RL = 10 kΩ, VREF = 0 V, and G = 5 (unless otherwise noted)
Output Voltage (5 V/div)
Output Voltage (5 V/div)
Time (50 ms/div)
Output Settling (0.002%/div)
Output Voltage
Output Settling
Output Settling (0.002%/div)
Output Voltage
Output Settling
Time (50 ms/div)
G062
G = 10, RL = 10 kΩ, CL = 100 pF
G063
G = 100, RL = 10 kΩ, CL = 100 pF
Figure 49. Large-Signal Response and Settling Time
Figure 50. Large-Signal Response and Settling Time
10M
1M
Impedance (Ω)
Output Voltage (5 V/div)
Output Settling (0.002 %/div)
Output Voltage
Output Settling
100k
10k
1k
100
1m 10m 100m
Time (100 ms/div)
1
G064
10 100 1k
Frequency (Hz)
10k 100k 1M 10M
G055
G = 1000, RL = 10 kΩ, CL = 100 pF
Figure 51. Large-Signal Response and Settling Time
Figure 52. Open-Loop Output Impedance
5
4
Offset Voltage (µV)
3
2
1
0
−1
−2
−3
−4
−5
0
40
80
120
Time (s)
160
200
G056
Figure 53. Change In Input Offset Voltage vs Warm-Up Time
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7 Detailed Description
7.1 Overview
The INA827 is a monolithic instrumentation amplifier (INA) based on a 36-V and a current feedback input
architecture. The INA827 also integrates laser-trimmed resistors to ensure excellent common mode rejection and
low gain error. The combination of the current feedback input and the precision resistors allows this device to
achieve outstanding dc precision as well as frequency response and high frequency common mode
rejection(TBD this is more like a Layout text. Overview is generally an overview of the device.)
The Overview section provides a top-level description of what the device is and what it does. Detailed
descriptions of the features and functions appear in subsequent subsections. Guidelines ● Include a summary of
standards met by the device (if any). ● List modes and states of operation (from the user's perspective) and key
features within each functional mode for quick reference. Use the following sections to provide detail on these
modes and features.
7.2 Functional Block Diagram
V+
0.1 mF
8
1
-IN
10 kW
50 kW
A1
VO = G ´ (VIN+ - VIN-)
2
8 kW
RG
G=5+
A3
8 kW
7
+
3
Load VO
10 kW
+IN
4
80 kW
RG
50 kW
A2
6
REF
TI Device
5
0.1 mF
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Figure 54. INA827 Block Diagram
Figure 55. Simplified Block Diagram (TBD only simplified op amp goes here but this is a PNG and I can't
edit it)
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7.3 Feature Description
7.3.1 Setting the Gain
Device gain is set by a single external resistor (RG), connected between pins 2 and 3. The value of RG is
selected according to Equation 1:
80 kW
5+
RG
(1)
Table 1 lists several commonly-used gains and resistor values. The on-chip resistors are laser-trimmed to
accurate absolute values. The accuracy and temperature coefficients of these resistors are included in the gain
accuracy and drift specifications of the INA827.
Table 1. Commonly-Used Gains and Resistor Values
DESIRED GAIN (V/V)
RG (Ω)
5
—
NEAREST 1% RG (Ω)
—
10
16.00k
15.8k
20
5.333k
5.36k
50
1.778k
1.78k
100
842.1
845
200
410.3
412
500
161.6
162
1000
80.40
80.6
7.3.1.1 Gain Drift
The stability and temperature drift of the external gain setting resistor (RG) also affects gain. The RG contribution
to gain accuracy and drift can be directly inferred from the gain of Equation 1.
The best gain drift of 1 ppm per degree Celsius can be achieved when the INA827 uses G = 5 without RG
connected. In this case, the gain drift is limited only by the slight temperature coefficient mismatch of the
integrated 50-kΩ resistors in the differential amplifier (A3). At gains greater than 5, the gain drift increases as a
result of the individual drift of the resistors in the feedback of A1 and A2, relative to the drift of the external gain
resistor RG. Process improvements to the temperature coefficient of the feedback resistors now enable a
maximum gain drift of the feedback resistors to be specified at 35 ppm per degree Celsius, thus significantly
improving the overall temperature stability of applications using gains greater than 5.
Low resistor values required for high gains can make wiring resistance important. Sockets add to wiring
resistance and contribute additional gain error (such as possible unstable gain errors) at gains of approximately
100 or greater. To ensure stability, avoid parasitic capacitances greater than a few picofarads at RG connections.
Careful matching of any parasitics on both RG pins maintains optimal CMRR over frequency; see the Typical
Characteristics section.
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7.3.2 Offset Trimming
Most applications require no external offset adjustment; however, if necessary, adjustments can be made by
applying a voltage to the REF pin. Figure 56 shows an optional circuit for trimming the output offset voltage. The
voltage applied to the REF pin is summed at the output. The op amp buffer provides low impedance at the REF
pin to preserve good common-mode rejection.
VIN-
V+
RG
VIN+
VO
INA827
100 mA
1/2 REF200
REF
100 W
OPA333
±10 mV
Adjustment Range
10 kW
100 W
100 mA
1/2 REF200
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Figure 56. Optional Trimming of Output Offset Voltage
7.3.3 Input Common-Mode Range
The linear input voltage range of the INA827 input circuitry extends from the negative supply voltage to 1 V
below the positive supply, and maintains 88-dB (minimum) common-mode rejection throughout this range. The
common-mode range for most common operating conditions is described in Figure 14 and Figure 35 through
Figure 38. The INA827 can operate over a wide range of power supplies and VREF configurations, thus making a
comprehensive guide to common-mode range limits for all possible conditions impractical to provide.
The most commonly overlooked overload condition occurs when a circuit exceeds the output swing of A1 and A2,
which are internal circuit nodes that cannot be measured. Calculating the expected voltages at the output of A1
and A2 (see Figure 57) provides a check for the most common overload conditions. The A1 and A2 designs are
identical and the outputs can swing to within approximately 100 mV of the power-supply rails. For example, when
the A2 output is saturated, A1 can continue to be in linear operation and responding to changes in the
noninverting input voltage. This difference can give the appearance of linear operation but the output voltage is
invalid.
A single-supply instrumentation amplifier has special design considerations. To achieve a common-mode range
that extends to single-supply ground, the INA827 employs a current-feedback topology with PNP input
transistors; see Figure 57. The matched PNP transistors (Q1 and Q2) shift the input voltages of both inputs up by
a diode drop and (through the feedback network) shift the output of A1 and A2 by approximately +0.8 V. With
both inputs and VREF at single-supply ground (negative power supply), the output of A1 and A2 is well within the
linear range, allowing differential measurements to be made at the GND level. As a result of this input levelshifting, the voltages at pins 2 and 3 are not equal to the respective input pin voltages (pins 1 and 4). For most
applications, this inequality is not important because only the gain-setting resistor connects to these pins.
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7.3.4 Inside the INA827
See Figure 61 for a simplified representation of the INA827. A more detailed diagram (shown in Figure 57)
provides additional insight into the INA827 operation.
Each input is protected by two field-effect transistors (FETs) that provide a low series resistance under normal
signal conditions and preserve excellent noise performance. When excessive voltage is applied, these transistors
limit input current to approximately 8 mA.
The differential input voltage is buffered by Q1 and Q2 and is applied across RG, causing a signal current to flow
through RG, R1, and R2. The output difference amplifier (A3) removes the common-mode component of the input
signal and refers the output signal to the REF pin.
The equations shown in Figure 57 describe the output voltages of A1 and A2. The VBE and voltage drop across
R1 and R2 produce output voltages on A1 and A2 that are approximately 0.8 V higher than the input voltages.
V+
V+
RG
(External)
50 kW
R1
8 kW
A1 Out = VCM + VBE + 0.125 V - VD/2 ´ G
A2 Out = VCM + VBE + 0.125 V + VD/2 ´ G
Output Swing Range A1, A2, (V+) - 0.1 V to (V-) + 0.1 V
V-
R2
8 kW
V-
V+
10 kW
VOUT
A3
10 kW
V+
VO = G ´ (VIN+ - VIN-) + VREF
Linear Input Range A3 = (V+) - 0.9 V to (V-) + 0.1 V
V-
50 kW
REF
VV+
V+
-IN
Q1
VD/2
Overvoltage
Protection
Q2
C1
V-
A1
A2
RB
VCM
C2
V-
VB
Overvoltage
Protection
RB
VD/2
V+IN
Figure 57. INA827 Simplified Circuit Diagram
7.3.5 Input Protection
The INA827 inputs are individually protected for voltages up to ±40 V. For example, a condition of –40 V on one
input and +40 V on the other input does not cause damage. However, if the input voltage exceeds [(V–) – 2 V]
and the signal source current drive capability exceeds 3.5 mA, the output voltage switches to the opposite
polarity; see Figure 14. This polarity reversal can easily be avoided by adding a 10-kΩ resistance in series with
both inputs.
Internal circuitry on each input provides low series impedance under normal signal conditions. If the input is
overloaded, the protection circuitry limits the input current to a safe value of approximately 8 mA. Figure 14
illustrates this input current limit behavior. The inputs are protected even if the power supplies are disconnected
or turned off.
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7.3.6 Input Bias Current Return Path
The INA827 input impedance is extremely high—approximately 20 GΩ. However, a path must be provided for
the input bias current of both inputs. This input bias current is typically 35 nA. High input impedance means that
this input bias current changes very little with varying input voltage.
Input circuitry must provide a path for this input bias current for proper operation. Figure 58 shows various
provisions for an input bias current path. Without a bias current path, the inputs float to a potential that exceeds
the INA827 common-mode range, and the input amplifiers saturate. If the differential source resistance is low,
the bias current return path can be connected to one input (as shown in the thermocouple example in Figure 58).
With higher source impedance, using two equal resistors provides a balanced input with possible advantages of
lower input offset voltage as a result of bias current and better high-frequency common-mode rejection.
Microphone,
hydrophone,
and so forth.
TI Device
47 kW
47 kW
Thermocouple
TI Device
10 kW
TI Device
Center tap provides
bias current return.
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Figure 58. Providing an Input Common-Mode Current Path
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7.3.7 Reference Pin
The INA827 output voltage is developed with respect to the voltage on the reference pin. Often, in dual-supply
operation, the reference pin (pin 6) is connected to the low-impedance system ground. Offsetting the output
signal to a precise mid-supply level (for example, 2.5 V in a 5-V supply environment) can be useful in singlesupply operation. The signal can be shifted by applying a voltage to the device REF pin, which can be useful
when driving a single-supply ADC.
For best performance, keep any source impedance to the REF pin below 5 Ω. Referring to Figure 61, the
reference resistor is at one end of a 50-kΩ resistor. Additional impedance at the REF pin adds to this 50-kΩ
resistor. The imbalance in resistor ratios results in degraded common-mode rejection ratio (CMRR).
Figure 59 shows two different methods of driving the reference pin with low impedance. The OPA330 is a lowpower, chopper-stabilized amplifier and therefore offers excellent stability over temperature. The OPA330 is
available in the space-saving SC70 and even smaller chip-scale package. The REF3225 is a precision reference
in a small SOT23-6 package.
+5 V
VIN-
+5 V
RG
VOUT
INA827
VIN-
REF
VIN+
+5 V
RG
VOUT
INA827
REF
+5 V
VIN+
+2.5 V
OPA330
a) Level shifting using the OPA330 as a low-impedance buffer
REF3225
+5 V
b) Level shifting using the low-impedance output of the REF3225
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Figure 59. Options for Low-Impedance Level Shifting
7.3.8 Dynamic Performance
Figure 19 illustrates that, despite having low quiescent current of only 200 µA, the INA827 achieves much wider
bandwidth than other instrumentation amplifiers (INAs) in its class. This achievement is a result of using TI’s
proprietary high-speed precision bipolar process technology. The current-feedback topology provides the INA827
with wide bandwidth even at high gains. Settling time also remains excellent at high gain because of a 1.5-V/µs
high slew rate.
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7.3.9 Operating Voltage
The INA827 operates over a power-supply range of +3 V to +36 V (±1.5 V to ±18 V). Supply voltages higher than
40 V (±20 V) can permanently damage the device. Parameters that vary over supply voltage or temperature are
shown in the Typical Characteristics section.
7.3.9.1 Low-Voltage Operation
The INA827 can operate on power supplies as low as ±1.5 V. Most parameters vary only slightly throughout this
supply voltage range; see the Typical Characteristics section. Operation at very low supply voltage requires
careful attention to assure that the input voltages remain within the linear range. Voltage swing requirements of
the internal nodes limit the input common-mode range with low power-supply voltage. Figure 7 to Figure 13 and
Figure 35 to Figure 38 describe the linear operation range for various supply voltages, reference connections,
and gains.
7.3.10 Error Sources
Most modern signal-conditioning systems calibrate errors at room temperature. However, calibration of errors
that result from a change in temperature is normally difficult and costly. Therefore, these errors must be
minimized by choosing high-precision components such as the INA827 that have improved specifications in
critical areas that effect overall system precision. Figure 60 shows an example application.
+15 V
RS+ = 10 kW
VDIFF = 1 V
16 kW
VOUT
TI Device
REF
RS- = 9.9 kW
VCM = 10 V
Signal Bandwidth: 5 kHz
-15 V
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Figure 60. Example Application With G = 10 V/V and 1-V Differential Voltage
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Resistor-adjustable INAs such as the INA827 yield the lowest gain error at G = 5 because of the inherently wellmatched drift of the internal resistors of the differential amplifier. At gains greater than 5 (for instance, G = 10 V/V
or G = 100 V/V) gain error becomes a significant error source because of the resistor drift contribution of the
feedback resistors in conjunction with the external gain resistor. Except for very high gain applications, gain drift
is by far the largest error contributor compared to other drift errors (such as offset drift). The INA827 offers the
lowest gain error over temperature in the marketplace for both G > 5 and G = 5 (no external gain resistor).
Table 2 summarizes the major error sources in common INA applications and compares the two cases of G = 5
(no external resistor) and G = 10 (with a 16-kΩ external resistor). As shown in Table 2, although the static errors
(absolute accuracy errors) in G = 5 are almost twice as great as compared to G = 10, there is a great reduction
in drift errors because of the significantly lower gain error drift. In most applications, these static errors can
readily be removed during calibration in production. All calculations refer the error to the input for easy
comparison and system evaluation.
Table 2. Error Calculation
INA827
ERROR SOURCE
ERROR CALCULATION
SPECIFICATION
G = 10 ERROR
(ppm)
G = 1 ERROR
(ppm)
ABSOLUTE ACCURACY AT +25°C
Input offset voltage (µV)
VOSI / VDIFF
150
150
150
Output offset voltage (µV)
VOSO / (G × VDIFF)
2000
200
400
Input offset current (nA)
IOS × maximum (RS+, RS–) / VDIFF
5
50
50
94 (G = 10),
88 (G = 5)
200
398
600
998
25 (G = 10),
1 (G = 5)
2000
80
CMRR (dB)
VCM / (10CMRR / 20 × VDIFF)
Total absolute accuracy error (ppm)
DRIFT TO +105°C
Gain drift (ppm/°C)
GTC × (TA – 25)
Input offset voltage drift (μV/°C)
(VOSI_TC / VDIFF) × (TA – 25)
5
200
200
Output offset voltage drift (μV/°C)
[VOSO_TC / ( G × VDIFF)] × (TA – 25)
30
240
240
2440
760
5
5
5
eNI = 17
eNO = 250
6
6
11
11
3051
1769
Total drift error (ppm)
RESOLUTION
Gain nonlinearity (ppm of FS)
Voltage noise (1 kHz)
BW ´
(eNI2 +
eNO
G
2
6
´
VDIFF
Total resolution error (ppm)
TOTAL ERROR
Total error
Total error = sum of all error sources
7.4 Device Functional Modes
The INA827 has a single functional mode and is operational when the power-supply voltage is greater than 3 V
(±1.5 V). The maximum power-supply voltage for the INA827 is 36 V (±18 V).
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8 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
Figure 61 shows the basic connections required for device operation. Good layout practice mandates that bypass
capacitors are placed as close to the device pins as possible.
The INA827 output is referred to the output reference (REF) pin, which is normally grounded. This connection
must be low-impedance to assure good common-mode rejection. Although 5 Ω or less of stray resistance can be
tolerated when maintaining specified CMRR, small stray resistances of tens of ohms in series with the REF pin
can cause noticeable degradation in CMRR.
V+
0.1 mF
8
(1)
RS
-IN
1
10 kW
50 kW
A1
VO = G ´ (VIN+ - VIN-)
2
8 kW
RG
G=5+
A3
8 kW
7
+
3
+IN
Load VO
10 kW
(1)
RS
4
80 kW
RG
50 kW
A2
6
REF
TI Device
5
0.1 mF
VCopyright © 2016, Texas Instruments Incorporated
(1) This resistor is optional if the input voltage remains above [(V–) – 2 V] or if the signal source current drive capability is limited to less than
3.5 mA. See the Input Protection section for more details.
Figure 61. Basic Connections
24
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8.2 Typical Application
An example programmable logic controller (PLC) input application using an INA827 is shown in Figure 62.
Figure 62. ±10-V, 4-mA to 20-mA PLC Input
8.2.1 Design Requirements
This design has these requirements:
•
•
•
Supply voltage: ±15 V, 5 V
Inputs: ±10 V, ±20 mA
Output: 2.5 V, ±2.3 V
8.2.2 Detailed Design Procedure
There are two modes of operation for the circuit shown in Figure 62: current input and voltage input. This design
requires R1 >> R2 >> R3. Given this relationship, the current input mode transfer function is given by Equation 2.
VOUT-I = VD ´ G + VREF = -(IIN ´ R3) ´ G + VREF
where
•
G represents the gain of the instrumentation amplifier
(2)
The transfer function for the voltage input mode is shown by Equation 3.
R2
VOUT-V = VD ´ G + VREF = - VIN ´
´ G + VREF
R 1 + R2
(3)
R1 sets the input impedance of the voltage input mode. The minimum typical input impedance is 100 kΩ. 100 kΩ
is selected for R1 because increasing the R1 value also increases noise. The value of R3 must be extremely
small compared to R1 and R2. 20 Ω for R3 is selected because that resistance value is much smaller than R1 and
yields an input voltage of ±400 mV when operated in current mode (±20 mA).
Equation 4 can be used to calculate R2 given VD = ±400 mV, VIN = ±10 V, and R1 = 100 kΩ.
R2
R ´ VD
VD = VIN ´
® R2 = 1
= 4.167 kW
R 1 + R2
VIN - VD
(4)
The value obtained from Equation 4 is not a standard 0.1% value, so 4.12 kΩ is selected. R1 and R2 also use
0.1% tolerance resistors to minimize error.
The ideal gain of the instrumentation amplifier is calculated with Equation 5.
V
- VREF 4.8 V - 2.5 V
V
= 5.75 V
G = OUT
=
VD
400 mV
(5)
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Typical Application (continued)
Using the INA827 gain equation, the gain-setting resistor value is calculated as shown by Equation 6.
(6)
107 kΩ is a standard 0.1% resistor value that can be used in this design. Finally, the output RC filter components
are selected to have a –3-dB cutoff frequency of 1 MHz.
8.2.3 Application Curves
Figure 63. PLC Output Voltage vs Input Voltage
26
Figure 64. PLC Output Voltage vs Input Current
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9 Power Supply Recommendations
The nominal performance of the INA827 is specified with a supply voltage of ±15 V and a mid-supply reference
voltage. The device can also be operated using power supplies from ±1.5 V (3 V) to ±18 V (36 V) and non midsupply reference voltages with excellent performance. Parameters that can vary significantly with operating
voltage and reference voltage are illustrated in the Typical Characteristics section.
10 Layout
10.1 Layout Guidelines
Attention to good layout practices is always recommended. Keep traces short and, when possible, use a printed
circuit board (PCB) ground plane with surface-mount components placed as close to the device pins as possible.
Place 0.1-μF bypass capacitors close to the supply pins. Apply these guidelines throughout the analog circuit to
improve performance and provide benefits such as reducing the electromagnetic-interference (EMI) susceptibility.
10.1.1 CMRR vs Frequency
The INA827 pinout is optimized for achieving maximum CMRR performance over a wide range of frequencies.
However, care must be taken to ensure that both input paths are well-matched for source impedance and
capacitance to avoid converting common-mode signals into differential signals. In addition, parasitic capacitance
at the gain-setting pins can also affect CMRR over frequency. For example, in applications that implement gain
switching using switches or PhotoMOS® relays to change the value of RG, choose the component so that the
switch capacitance is as small as possible.
10.2 Layout Example
Figure 65. INA827 Example Layout
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11 Device and Documentation Support
11.1 Documentation Support
11.1.1 Related Documentation
For related documentation see the following:
• INA826 Precision, 200-μA Supply Current, 3-V to 36-V Supply Instrumentation Amplifier with Rail-to-Rail
Output (SBOS562)
• OPAx330 50-μV VOS, 0.25-μV/°C, 35-μA CMOS Operational Amplifiers Zero-Drift Series (SBOS432)
• REF32xx 4ppm/°C, 100μA, SOT23-6 Series Voltage Reference (SBVS058)
• TBD list anything else?
11.2 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
11.3 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
11.4 Trademarks
E2E is a trademark of Texas Instruments.
PhotoMOS is a registered trademark of Panasonic Electric Works Europe AG.
All other trademarks are the property of their respective owners.
11.5 Electrostatic Discharge Caution
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
11.6 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
28
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PACKAGE OPTION ADDENDUM
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10-Dec-2020
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
INA827AIDGK
ACTIVE
VSSOP
DGK
8
80
RoHS & Green
NIPDAUAG
Level-2-260C-1 YEAR
-40 to 125
IPSI
INA827AIDGKR
ACTIVE
VSSOP
DGK
8
2500
RoHS & Green
NIPDAUAG
Level-2-260C-1 YEAR
-40 to 125
IPSI
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may
reference these types of products as "Pb-Free".
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of
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