INA271-HT
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SBOS521D – SEPTEMBER 2010 – REVISED AUGUST 2013
VOLTAGE OUTPUT, UNIDIRECTIONAL MEASUREMENT CURRENT-SHUNT MONITOR
Check for Samples: INA271-HT
FEATURES
DESCRIPTION
•
•
•
The INA271 is a current-shunt monitor with voltage
output and can sense drops across current shunts at
common-mode voltages from –16V to +80V,
independent of the supply voltage. The INA271
pinouts readily enable filtering.
1
•
•
•
•
•
Wide Common-Mode Range: –16V to +80V
CMRR: 78dB
Accuracy:
±10mV Offset (max)
±7.5% Gain Error (max)
100μV/°C Offset Drift (max)
Bandwidth: Up to 130kHz
Transfer Function: 20V/V
Quiescent Current: 1600μA (max)
Power Supply: +2.7V to +18V
Provision for Filtering
The INA271 is available with a 20V/V output voltage
scale. The 130kHz bandwidth simplifies use in
current-control loops.
The INA271 operates from a single +2.7V to +18V
supply, drawing a maximum of 1600μA of supply
current. This device is specified over the extended
operating temperature range of –55°C to +210°C.
RS
APPLICATIONS
•
•
•
•
•
•
(1)
Load
Single-Pole Filter
Capacitor
Down-Hole Drilling
High Temperature Environments
SUPPORTS EXTREME TEMPERATURE
APPLICATIONS
•
•
•
•
-16V to +80V
Supply
Controlled Baseline
One Assembly/Test Site
One Fabrication Site
Available in Extreme (–55°C/210°C)
Temperature Range (1)
Extended Product Life Cycle
Extended Product-Change Notification
Product Traceability
Texas Instruments high temperature products
utilize highly optimized silicon (die) solutions
with design and process enhancements to
maximize performance over extended
temperatures.
+2.7V to +18V
IN+
PRE OUT
IN5kW
BUF IN
V+
5kW
OUT
A1
96kW
A2
RL
INA271
GND
Custom temperature ranges available
1
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2010–2013, Texas Instruments Incorporated
INA271-HT
SBOS521D – SEPTEMBER 2010 – REVISED AUGUST 2013
www.ti.com
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.
BARE DIE INFORMATION
DIE THICKNESS
BACKSIDE FINISH
BACKSIDE
POTENTIAL
BOND PAD
METALLIZATION COMPOSITION
BOND PAD
THICKNESS
11 mils.
Silicon with backgrind
GND
Al-Cu (0.5%)
598 nm
½
½
IN1
IN+
8
GND
2
NC
7
3
PRE OUT
1278 mm
½
762.3 mm
V+
6
40.5 mm
BUF IN
OUT
5
4
0.0
½
0.0
40.5 mm
Table 1. Bond Pad Coordinates in Microns
2
DISCRIPTION
PAD NUMBER
X min
Y min
X max
Y max
IN-
1
64.35
1012.41
139.41
1087.47
GND
2
61.83
648.81
136.89
723.87
PRE OUT
3
61.83
520.29
136.89
595.35
BUF IN
4
70.92
152.37
145.98
227.43
OUT
5
616.32
152.37
691.38
227.43
461.61
V+
6
621.99
386.55
697.05
NC
7
622.44
648.81
697.5
723.87
IN+
8
622.89
1012.41
697.95
1087.47
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SBOS521D – SEPTEMBER 2010 – REVISED AUGUST 2013
PIN CONFIGURATION
HKQ PACKAGE
(TOP VIEW)
AHD OR HKJ PACKAGE
(TOP VIEW)
IN- 1
GND 2
1
8
IN-
IN+
IN+
7 NC
NC
GND
V+
PRE OUT
8
INA271
PRE OUT 3
6
V+
BUF IN 4
5
OUT
OUT
5
BUF IN
4
HKQ as formed or HKJ mounted dead bug
NC denotes no internal connection
ORDERING INFORMATION (1)
TA
PACKAGE (2)
–55°C to 175°C
AHD
(1)
(2)
TOP-SIDE MARKING
INA271AHD
INA271AHD
INA271SKGD1
KGD (bare die)
–55°C to 210°C
ORDERABLE PART NUMBER
NA
INA271SKGD2
HKJ
INA271SHKJ
INA271SHKJ
HKQ
INA271SHKQ
INA271SHKQ
For the most current package and ordering information, see the Package Option Addendum at the end of this document, or see the TI
web site at www.ti.com.
Package drawings, thermal data, and symbolization are available at www.ti.com/packaging.
ABSOLUTE MAXIMUM RATINGS (1)
UNIT
Supply Voltage (VS)
+18
V
Differential, (VIN+) – (VIN–)
–18 to +18
V
Common-Mode
–16 to +80
V
GND – 0.3 to (V+) + 0.3
V
Analog Inputs, VIN+, VIN–:
Analog Output:
OUT and PRE OUT Pins
Input Current Into Any Pin
5
mA
Operating Temperature
–55 to +210
°C
Storage Temperature
–65 to +210
°C
Junction Temperature
+210
°C
Human Body Model
3000
V
Charged-Device Model
750
V
ESD Ratings:
(1)
Stresses above these ratings may cause permanent damage. Exposure to absolute maximum conditions for extended periods may
degrade device reliability. These are stress ratings only, and functional operation of the device at these or any other conditions beyond
those specified is not supported.
THERMAL CHARACTERISTICS FOR HKJ OR HKQ PACKAGE
over operating free-air temperature range (unless otherwise noted)
PARAMETER
θJC
Junction-to-case thermal resistance
to ceramic side of case
to top of case lid (metal side of case)
MIN
TYP
MAX
5.7
13.7
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UNIT
°C/W
3
INA271-HT
SBOS521D – SEPTEMBER 2010 – REVISED AUGUST 2013
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ELECTRICAL CHARACTERISTICS
At TA = +25°C, VS = +5V, VCM = +12V, VSENSE = 100mV, and PRE OUT connected to BUF IN, unless otherwise noted.
TA = –55°C to 125°C
PARAMETER
CONDITIONS
MIN
TYP
MAX
0.15
(VS –
0.2)/Gain
TA = –55°C to 175°C
MIN
TYP
MAX
TA = 210°C
MIN
TYP
MAX
UNIT
0.15
(VS –
0.2)/Gain
V
80
V
INPUT
Full-Scale Input
Voltage
VSENSE
Common-Mode
Input Range
VCM
Common-Mode
Rejection Ratio
CMRR
Offset Voltage,
RTI (1)
VOS
vs Temperature
VSENSE = (VIN+) + (VIN–)
–16
PSR
Input Bias Current,
VIN– Pin
–16
VIN+ = –16V to +80V
80
120
70
78
VIN+ = +12V to +80V
100
120
81
89
dVOS/dT
vs Power-Supply
80
VS = +2.7V to +18V,
VCM = +18V
IB
dB
±0.6
±3
±5
±10
mV
3.3
20
42
100
μV/°C
5
100
130
320
μV/V
±8
±16
±16
±25
μA
PRE OUT Output Impedance (2)
96
96
kΩ
Buffer Input Bias Current
–50
–50
nA
±0.03
±0.03
nA/°C
20
20
V/V
Buffer Input Bias Current
Temperature Coefficient
OUTPUT (VSENSE ≥ 20mV)
(3)
Gain: INA271 Total
Gain
G
Output Buffer Gain
GBUF
Total Gain Error
2
VSENSE = 20mV to 100mV
vs Temperature
±2
50
Total Output Error (4)
±1
Nonlinearity Error
Output Impedance
2
±0.2
VSENSE = 20mV to 100mV
RO
Maximum Capacitive Load
No Sustained Oscillation
VOLTAGE OUTPUT (5)
±1
V/V
±7.5
300
±3
±4.6
%
ppm/°C
±11.5
%
±0.002
±0.002
1.5
1.5
%
Ω
10
10
nF
RL = 10kΩ to GND
Swing to V+ Power-Supply Rail
(V+) –
0.05
(V+) –
0.2
(V+) –
0.13
(V+) –
0.2
V
Swing to GND (6)
VGND +
0.003
VGND +
0.05
VGND +
0.22
VGND +
0.42
V
FREQUENCY
RESPONSE
Bandwidth
BW
Phase Margin
Slew Rate
Settling Time (1%)
(1)
(2)
(3)
(4)
(5)
(6)
4
CLOAD = 5pF
130
130
kHz
CLOAD < 10nF
40
40
degrees
1
1
V/μs
2
2
μs
SR
tS
VSENSE = 10mV to 100mVPP,
CLOAD = 5pF
RTI means Referred-to-Input.
Initial resistor variation is ±30% with an additional –2200ppm/°C temperature coefficient.
For output behavior when VSENSE < 20mV, see the Application Information section Accuracy Variations as A Result of VSENSE and
Common-Mode Voltage.
Total output error includes effects of gain error and VOS.
See typical characteristic curve Output Swing vs Output Current and Application Information section Accuracy Variations as A Result of
VSENSE and Common-Mode Voltage.
Ensured by design; not production tested.
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ELECTRICAL CHARACTERISTICS (continued)
At TA = +25°C, VS = +5V, VCM = +12V, VSENSE = 100mV, and PRE OUT connected to BUF IN, unless otherwise noted.
TA = –55°C to 125°C
PARAMETER
CONDITIONS
MIN
TYP
MAX
TA = –55°C to 175°C
MIN
TYP
MAX
TA = 210°C
MIN
TYP
MAX
UNIT
NOISE < RTI (7)
Voltage Noise
Density
en
40
40
nV/√Hz
POWER SUPPLY
Operating Range
VS
Quiescent Current
IQ
2.7
18
2.7
18
VOUT = 2V
740
1200
1160
1600
VSENSE = 0mV
350
950
895
1600
V
μA
TEMPERATURE RANGE
Specified Temperature Range
–55
125
–55
210
°C
Operating Temperature Range
–55
125
–55
210
°C
(7)
RTI means Referred-to-Input.
1000
Estimated Life - Years
100
10
Electromigration Fail Mode
1
0
110
130
150
170
190
210
230
Continuous TJ - °C
(1)
See datasheet for absolute maximum and minimum recommended operating conditions.
(2)
Silicon operating life design goal is 10 years at 105°C junction temperature (does not include package interconnect
life).
Figure 1. INA271SKGD1/INA271SKGD2/INA271SHKJ/INA271SHKQ Operating Life Derating Chart
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TYPICAL CHARACTERISTICS
At TA = +25°C, VS = +12V, VCM = 12V, and VSENSE = 100mV, unless otherwise noted.
GAIN vs FREQUENCY
GAIN vs FREQUENCY
45
CLOAD = 1000pF
40
40
35
35
30
Gain (dB)
Gain (dB)
45
G = 20
25
G = 14
20
G = 20
25
G = 14
20
15
10
10
5
10k
100k
10k
1M
Frequency (Hz)
Figure 3.
COMMON-MODE AND POWER-SUPPLY REJECTION
vs FREQUENCY
140
VS = 18V
130
16
14
20V/V
12
10
8
14V/V
6
4
120
100
90
70
60
1200
1300
1000
1100
900
800
700
500
600
300
40
400
50
200
PSR
80
0
0
CMRR
110
2
100
1M
Figure 2.
Common-Mode and
Power-Supply Rejection (dB)
18
100k
Frequency (Hz)
GAIN PLOT
20
VOUT (V)
30
15
5
CLOAD = 0pF
10
100
1k
10k
100k
Frequency (Hz)
VSENSE (mV)
Figure 4.
TOTAL OUTPUT ERROR vs VSENSE
4.0
OUTPUT ERROR vs COMMON-MODE VOLTAGE
0.10
0.09
3.5
0.08
3.0
Output Error (%)
Total Output Error
(% error of the ideal output value)
Figure 5.
2.5
2.0
1.5
1.0
0.07
0.06
0.05
0.04
0.03
0.02
0.5
0.01
0
0
50
100 150
200
250 300
350 400 450 500
0
-16 -12 -8 -4
VSENSE (mV)
4
8
12 16 20
...
76 80
Common-Mode Voltage (V)
Figure 6.
6
0
Figure 7.
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SBOS521D – SEPTEMBER 2010 – REVISED AUGUST 2013
TYPICAL CHARACTERISTICS (continued)
At TA = +25°C, VS = +12V, VCM = 12V, and VSENSE = 100mV, unless otherwise noted.
POSITIVE OUTPUT VOLTAGE SWING
vs OUTPUT CURRENT
QUIESCENT CURRENT
vs OUTPUT VOLTAGE
1000
12
11
800
Sourcing Current
9
+25°C
8
700
-40°C
+125°C
7
6
IQ (mA)
Output Voltage (V)
900
VS = 12V
10
VS = 3V
5
Sourcing Current
+25°C
4
-40°C
2
1
+125°C
0
0
500
400
300
Output stage is designed
to source current. Current
sinking capability is
approximately 400mA.
3
600
200
100
0
5
10
20
15
25
30
0
2
1
3
4
Output Current (mA)
QUIESCENT CURRENT
vs COMMON-MODE VOLTAGE
OUTPUT SHORT-CIRCUIT CURRENT
vs SUPPLY VOLTAGE
34
VSENSE = 100mV:
VS = 12V
VS = 2.7V
675
IQ (mA)
8
Figure 9.
775
575
475
VS = 12V
375
7
6
Figure 8.
VSENSE = 0mV:
VS = 2.7V
275
Output Short-Circuit Current (mA)
875
5
9
10
Output Voltage (V)
175
-40°C
30
+25°C
26
+125°C
22
18
14
10
6
-16 -12 -8 -4
0
4
8
12 16
20
...
76 80
2.5 3.5
4.5
5.5 6.5
7.5
8.5
9.5 10.5 11.5 17
VCM (V)
Supply Voltage (V)
Figure 10.
Figure 11.
PREOUT OUTPUT RESISTANCE
PRODUCTION DISTRIBUTION
18
BUFFER GAIN vs FREQUENCY
200
150
Gain (dB)
Population
Phase
100
50
Gain
80
82
84
86
88
90
92
94
96
98
100
102
104
106
108
110
112
114
116
118
120
0
-50
10
100
1k
10k
100k
1M
10M
Frequency (Hz)
RPREOUT (kW)
Figure 12.
Figure 13.
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TYPICAL CHARACTERISTICS (continued)
At TA = +25°C, VS = +12V, VCM = 12V, and VSENSE = 100mV, unless otherwise noted.
50mV/div
8
LARGE-SIGNAL STEP RESPONSE
10mV TO 100mV INPUT
500mV/div
SMALL-SIGNAL STEP RESPONSE
10mV TO 20mV INPUT
10ms/div
10ms/div
Figure 14.
Figure 15.
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SBOS521D – SEPTEMBER 2010 – REVISED AUGUST 2013
APPLICATIONS INFORMATION
BASIC CONNECTION
POWER SUPPLY
Figure 16 shows the basic connection of the IINA271.
The input pins, IN+ and IN–, should be connected as
closely as possible to the shunt resistor to minimize
any resistance in series with the shunt resistance.
The input circuitry of the INA271 can accurately
measure beyond its power-supply voltage, V+. For
example, the V+ power supply can be 5V, whereas
the load power-supply voltage is up to +80V. The
output voltage range of the OUT terminal, however, is
limited by the voltages on the power-supply pin.
Power-supply bypass capacitors are required for
stability. Applications with noisy or high-impedance
power supplies may require additional decoupling
capacitors to reject power-supply noise. Minimum
bypass capacitors of 0.01μF and 0.1μF in value
should be placed close to the supply pins. Although
not mandatory, an additional 10mF electrolytic
capacitor placed in parallel with the other bypass
capacitors may be useful in applications with
particularly noisy supplies.
SELECTING RS
The value chosen for the shunt resistor, RS, depends
on the application and is a compromise between
small-signal accuracy and maximum permissible
voltage loss in the measurement line. High values of
RS provide better accuracy at lower currents by
minimizing the effects of offset, while low values of
RS minimize voltage loss in the supply line. For most
applications, best performance is attained with an RS
value that provides a full-scale shunt voltage range of
50mV to 100mV. Maximum input voltage for accurate
measurements is (VS – 0.2)/Gain.
RS
-16V to +80V
Supply
Load
Single-Pole Filter
Capacitor
+2.7V to +18V
IN+
PRE OUT
IN5kW
BUF IN
0.01mF
V+
0.1mF
5kW
OUT
A1
96kW
A2
RL
INA271
GND
Figure 16. INA271 Basic Connections
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TRANSIENT PROTECTION
resistors in series with the inputs since the internal
gain resistors can vary up to ±30%, but is tightly
matched (if gain accuracy is not important, then
resistors can be added in series with the INA271
inputs with two equal resistors on each input).
The –16V to +80V common-mode range of the
INA271 is ideal for withstanding automotive fault
conditions ranging from 12V battery reversal up to
+80V transients, since no additional protective
components are needed up to those levels. In the
event that the INA271 is exposed to transients on the
inputs in excess of their ratings, external transient
absorption with semiconductor transient absorbers
(zeners or Transzorbs) will be necessary.
OUTPUT VOLTAGE RANGE
The output of the INA271 is accurate within the
output voltage swing range set by the power-supply
pin, V+.
Use of MOVs or VDRs is not recommended except
when they are used in addition to a semiconductor
transient absorber. Select the transient absorber such
that it will never allow the INA271 to be exposed to
transients greater than 80V (that is, allow for transient
absorber tolerance, as well as additional voltage
because of transient absorber dynamic impedance).
Despite the use of internal zener-type ESD
protection, the INA271 is not suited to using external
The INA271 readily enables the inclusion of filtering
between the preamp output and buffer input. Singlepole filtering can be accomplished with a single
capacitor because of the 96kΩ output impedance at
PRE OUT on pin 3, as shown in Figure 17a.
The INA271 readily lends itself to second-order
Sallen-Key configurations, as shown in Figure 17b.
When designing these configurations consider that
the PRE OUT 96kΩ output impedance exhibits an
initial variation of ±30% with the addition of a
–2200ppm/°C temperature coefficient.
RS
Load
Supply
RS
Load
Supply
Second-Order, Sallen-Key Filter Connection
CFILT
Single-Pole Filter
Capacitor
CFILT
RS
+2.7V to +18V
IN+
PRE OUT
IN5kW
BUF IN
+2.7V to +18V
V+
IN+
5kW
5kW
Output
A1
BUF IN
V+
5kW
A1
96kW
A2
PRE OUT
IN-
Output
96kW
A2
RL
RL
INA271
INA271
GND
a) Single-Pole Filter
GND
b) Second-Order, Sallen-Key Filter
Figure 17. The INA271 can be easily connected for first- or second-order filtering. Remember to use the
appropriate buffer gain of 2 when designing Sallen-Key configurations.
10
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ACCURACY VARIATIONS AS A RESULT OF
VSENSE AND COMMON-MODE VOLTAGE
The accuracy of the INA271 current shunt monitor is
a function of two main variables: VSENSE (VIN+ – VIN–)
and common-mode voltage, VCM, relative to the
supply voltage, VS. VCM is expressed as (VIN+ +
VIN–)/2; however, in practice, VCM is seen as the
voltage at VIN+ because the voltage drop across
VSENSE is usually small.
This section addresses the accuracy of these specific
operating regions:
Normal Case 1: VSENSE ≥ 20mV, VCM ≥ VS
Normal Case 2: VSENSE ≥ 20mV, VCM < VS
Low VSENSE Case 1:
VSENSE < 20mV, –16V ≤ VCM < 0
Low VSENSE Case 2:
VSENSE < 20mV, 0V ≤ VCM ≤ VS
Low VSENSE Case 3:
VSENSE < 20mV, VS < VCM ≤ 80V
Normal Case 1: VSENSE ≥ 20mV, VCM ≥ VS
This region of operation provides the highest
accuracy. Here, the input offset voltage is
characterized and measured using a two-step
method. First, the gain is determined by Equation 1.
VOUT1 - VOUT2
G=
100mV - 20mV
(1)
Normal Case 2: VSENSE ≥ 20mV, VCM < VS
This region of operation has slightly less accuracy
than Normal Case 1 as a result of the common-mode
operating area in which the part functions, as seen in
the Output Error vs Common-Mode Voltage curve
(Figure 7). As noted, for this graph VS = 12V; for VCM
< 12V, the Output Error increases as VCM becomes
less than 12V, with a typical maximum error of
0.005% at the most negative VCM = –16V.
Low VSENSE Case 1:
VSENSE < 20mV, –16V ≤ VCM < 0; and
Low VSENSE Case 3:
VSENSE < 20mV, VS < VCM ≤ 80V
Although the INA271 is not designed for accurate
operation in either of these regions, some
applications are exposed to these conditions. For
example, when monitoring power supplies that are
switched on and off while VS is still applied to the
INA271, it is important to know what the behavior of
the device will be in these regions.
As VSENSE approaches 0mV, in these VCM regions,
the device output accuracy degrades. A larger-thannormal offset can appear at the current shunt monitor
output with a typical maximum value of VOUT = 60mV
for VSENSE = 0mV. As VSENSE approaches 20mV, VOUT
returns to the expected output value with accuracy as
specified in the Electrical Characteristics. Figure 18
shows this effect (Gain = 20).
0.40
where:
VOUT1 = Output Voltage with VSENSE = 100mV
VOUT2 = Output Voltage with VSENSE = 20mV
0.36
0.32
(2)
In the Typical Characteristics, the Output Error vs
Common-Mode Voltage curve (Figure 7) shows the
highest accuracy for the this region of operation. In
this plot, VS = 12V; for VCM ≥ 12V, the output error is
at its minimum. This case is also used to create the
VSENSE ≥ 20mV output specifications in the Electrical
Characteristics table.
0.28
VOUT (V)
Then the offset voltage is measured at VSENSE =
100mV and referred to the input (RTI) of the current
shunt monitor, as shown in Equation 2.
VOUT1
VOSRTI (Referred-To-Input) =
- 100mV
G
0.24
Actual
0.20
0.16
Ideal
0.12
0.08
0.04
0
0
2
4
6
8
10
12
14
16
18
20
VSENSE (mV)
Figure 18. Example for Low VSENSE Cases 1 and 3
(Gain = 20)
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Product Folder Links: INA271-HT
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INA271-HT
SBOS521D – SEPTEMBER 2010 – REVISED AUGUST 2013
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Low VSENSE Case 2: VSENSE < 20mV, 0V ≤ VCM ≤ VS
SHUTDOWN
This region of operation is the least accurate for the
INA271. To achieve the wide input common-mode
voltage range, this device uses two op amp front
ends in parallel. One op amp front end operates in
the positive input common-mode voltage range, and
the other in the negative input region. For this case,
neither of these two internal amplifiers dominates and
overall loop gain is very low. Within this region, VOUT
approaches voltages close to linear operation levels
for Normal Case 2.
The INA271 does not provide a shutdown pin;
however, because it consumes a quiescent current
less than 1mA, it can be powered by either the output
of logic gates or by transistor switches to supply
power. Driving the gate low shuts down the INA271.
Use a totem-pole output buffer or gate that can
provide sufficient drive along with 0.1μF bypass
capacitor, preferably ceramic with good highfrequency characteristics. This gate should have a
supply voltage of 3V or greater because the INA271
requires a minimum supply greater than 2.7V. In
addition to eliminating quiescent current, this gate
also turns off the 10μA bias current present at each
of the inputs. Note that the IN+ and IN– inputs are
able to withstand full common-mode voltage under all
powered and under-powered conditions. An example
shutdown circuit is illustrated in Figure 20.
This deviation from linear operation becomes greatest
the closer VSENSE approaches 0V. Within this region,
as VSENSE approaches 20mV, device operation is
closer to that described by Normal Case 2. Figure 19
illustrates this behavior for the INA271. The VOUT
maximum peak for this case is determined by
maintaining a constant VS, setting VSENSE = 0mV, and
sweeping VCM from 0V to VS. The exact VCM at which
VOUT peaks during this case varies from part to part.
The maximum peak voltage for the INA271 is 0.4V.
0.48
0.44 INA271 VOUT Limit
(1)
VCM1
0.40
Ideal
0.36
VCM2
VOUT (V)
0.32
0.28
VCM3
0.24
0.20
0.16
VOUT limit at VSENSE = 0mV,
0 £ VCM1 £ VS
VCM4
0.12
VCM2, VCM3, and VCM4 illustrate the variance
from part to part of the VCM that can cause
maximum VOUT with VSENSE < 20mV.
0.08
0.04
0
0
2
4
6
8
10
12
14
16
18
20
22
VSENSE (mV)
NOTE: (1) INA271 VOUT Limit = 0.4V. INA270 VOUT Limit = 0.28V.
Figure 19. Example for Low VSENSE Case 2
(Gain = 20)
12
24
RFI/EMI
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. Small ceramic
capacitors placed directly across amplifier inputs can
reduce RFI/EMI sensitivity. PCB layout should locate
the amplifier as far away as possible from RFI
sources. Sources can include other components in
the same system as the amplifier itself, such as
inductors (particularly switched inductors handling a
lot of current and at high frequencies). RFI can
generally be identified as a variation in offset voltage
or dc signal levels with changes in the interfering RF
signal. If the amplifier cannot be located away from
sources of radiation, shielding may be needed.
Twisting wire input leads makes them more resistant
to RF fields. The difference in input pin location of the
INA271 versus the INA193–INA198 may provide
different EMI performance.
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Copyright © 2010–2013, Texas Instruments Incorporated
Product Folder Links: INA271-HT
INA271-HT
www.ti.com
SBOS521D – SEPTEMBER 2010 – REVISED AUGUST 2013
IL
RS
-16V to +80V
Supply
Single-Pole Filter
Capacitor
IN+
Negative
and
Positive
Common-Mode
Voltage
PRE OUT
IN5kW
Load
BUF IN
V+
5kW
V+ > 3V
OUT
A1
74HC04
0.1mF
96kW
A2
RL
INA271
GND
(1)
74HC04 is not tested or characterized at 210°C.
Figure 20. INA271 Example Shutdown Circuit
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Copyright © 2010–2013, Texas Instruments Incorporated
Product Folder Links: INA271-HT
13
PACKAGE OPTION ADDENDUM
www.ti.com
15-Jun-2022
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)
Samples
(4/5)
(6)
INA271SHKJ
ACTIVE
CFP
HKJ
8
25
RoHS & Green
Call TI
N / A for Pkg Type
-55 to 210
INA271
SHKJ
Samples
INA271SHKQ
ACTIVE
CFP
HKQ
8
25
RoHS & Green
AU
N / A for Pkg Type
-55 to 210
INA271S
HKQ
Samples
INA271SKGD1
ACTIVE
XCEPT
KGD
0
252
RoHS & Green
Call TI
N / A for Pkg Type
-55 to 210
Samples
INA271SKGD2
ACTIVE
XCEPT
KGD
0
10
RoHS & Green
Call TI
N / A for Pkg Type
-55 to 210
Samples
(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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