INA293
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
INA293 –4-V to 110-V, 1.3-MHz, Ultra-Precise Current Sense Amplifier
1 Features
3 Description
•
The INA293 is a ultra-precise current sense amplifier
that can measure voltage drops across shunt resistors
over a wide common-mode range from –4 V to 110
V. The negative common-mode voltage allows the
device to operate below ground, thus accommodating
precise measurement of recirculating currents in halfbridge applications. The combination of a low offset
voltage, small gain error and high DC CMRR enables
highly accurate current measurement. The INA293 is
not only designed for DC current measurement, but
also for high-speed applications (ex. Fast over-current
protection) with a high bandwidth of 1.3 MHz and an
85-dB AC CMRR (at 50 kHz).
•
•
•
•
•
•
Wide common-mode voltage:
– Operational voltage: −4 V to +110 V
– Survival voltage: −20 V to +120 V
Excellent CMRR:
– 160-dB DC-CMRR
– 85-dB AC-CMRR at 50 kHz
Accuracy:
– Gain:
• Gain error: ±0.15% (maximum)
• Gain drift: ±10 ppm/ °C (maximum)
– Offset:
• Offset voltage: ±15 µV (typical)
• Offset drift: ±0.05 µV/ °C (typical)
Available gains:
– INA293A1, INA293B1 : 20 V/V
– INA293A2, INA293B2 : 50 V/V
– INA293A3, INA293B3 : 100 V/V
– INA293A4, INA293B4 : 200 V/V
– INA293A5, INA293B5 : 500 V/V
High bandwidth: 1.3 MHz
Slew rate: 2.5 V/µs
Quiescent current: 1.5 mA
2 Applications
•
•
•
•
•
Active antenna system mMIMO (AAS)
Macro remote radio unit (RRU)
48-V rack server
48-V merchant network & server power supply
(PSU)
48-V battery management systems (BMS)
The INA293 operates from a single 2.7-V to 20V supply, drawing 1.5 mA of supply current. The
INA293 is available with five gain options: 20 V/V,
50 V/V, 100 V/V, 200 V/V, and 500 V/V. These gain
options address wide dynamic range current-sensing
applications.
The INA293 is specified over an operating
temperature range of −40 °C to +125 °C and is
offered in a space-saving SOT-23 package with two
pin-out variants.
Device Information(1)
PART NUMBER
INA293
(1)
PACKAGE
SOT-23 (5)
BODY SIZE (NOM)
2.90 mm × 1.60 mm
For all available packages, see the package option
addendum at the end of the data sheet.
VS
VCM
ISENSE
R1
IN+
RSENSE
+
Bias
R1
IN±
Load
Current
Feedback
OUT
-
Buffer
RL
GND
Functional Block Diagram
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.
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
Table of Contents
1 Features............................................................................1
2 Applications..................................................................... 1
3 Description.......................................................................1
4 Revision History.............................................................. 2
5 Pin Configuration and Functions...................................3
6 Specifications.................................................................. 4
6.1 Absolute Maximum Ratings ....................................... 4
6.2 ESD Ratings .............................................................. 4
6.3 Recommended Operating Conditions ........................5
6.4 Thermal Information ...................................................5
6.5 Electrical Characteristics ............................................5
6.6 Typical Characteristics................................................ 7
7 Detailed Description......................................................13
7.1 Overview................................................................... 13
7.2 Functional Block Diagram......................................... 13
7.3 Feature Description...................................................13
7.4 Device Functional Modes..........................................15
8 Application and Implementation.................................. 16
8.1 Application Information............................................. 16
8.2 Typical Application.................................................... 18
9 Power Supply Recommendations................................19
10 Layout...........................................................................20
10.1 Layout Guidelines................................................... 20
10.2 Layout Example...................................................... 20
11 Device and Documentation Support..........................21
11.1 Documentation Support.......................................... 21
11.2 Receiving Notification of Documentation Updates.. 21
11.3 Support Resources................................................. 21
11.4 Trademarks............................................................. 21
11.5 Electrostatic Discharge Caution.............................. 21
11.6 Glossary.................................................................. 21
12 Mechanical, Packaging, and Orderable
Information.................................................................... 21
4 Revision History
Changes from Revision * (December 2019) to Revision A (June 2021)
Page
• Changed data sheet title from: INA293 –4-V to 110-V, 1-MHz, High-Precision Current Sense Amplifier to:
INA293 –4-V to 110-V, 1.3-MHz, High-Precision Current Sense Amplifier......................................................... 1
• Updated the numbering format for tables, figures, and cross-references throughout the document..................1
• Changed 'high-precision' to 'ultra-precise' in Description section....................................................................... 1
2
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
5 Pin Configuration and Functions
OUT
1
GND
2
IN+
3
5
4
Vs
OUT
1
GND
2
Vs
3
IN±
Not to scale
5
IN±
4
IN+
Not to scale
Figure 5-1. INA293A: DBV Package 5-Pin SOT-23
Top View
Figure 5-2. INA293B: DBV Package 5-Pin SOT-23
Top View
Table 5-1. Pin Functions
PIN
NAME
TYPE
DESCRIPTION
INA293A
INA293B
GND
2
2
Ground Ground
OUT
1
1
Output
Output voltage
Vs
5
3
Power
Power supply
IN+
3
4
Input
Shunt resistor positive sense input
IN–
4
5
Input
Shunt resistor negative sense input
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
3
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
6 Specifications
6.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted)(1)
Supply Voltage
(Vs)
Analog Inputs,
VIN+, VIN– (2)
Differential (VIN+) – (VIN–), INA293A5, INA293B5
Differential (VIN+) – (VIN–), All others
Common - mode
Output
TA
Operating temperature
TJ
Junction temperature
Tstg
Storage temperature
(1)
(2)
MIN
MAX
–0.3
22
–6
6
–12
12
UNIT
V
V
–20
120
GND – 0.3
Vs + 0.3
V
–55
150
°C
150
°C
150
°C
–65
Stresses beyond those listed under Absolute Maximum Rating 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 Condition. Exposure to absolute-maximum-rated conditions for extended periods may affect device
reliability.
VIN+ and VIN– are the voltages at the IN+ and IN– pins, respectively.
6.2 ESD Ratings
VALUE
V(ESD)
(1)
(2)
4
Electrostatic discharge
Human body model (HBM), per ANSI/ESDA/
JEDEC JS-001, all pins(1)
±2000
Charged device model (CDM), per JEDEC
specification JESD22-C101, all pins(2)
±1000
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.
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
6.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
NOM
MAX
VCM
Common-mode input range
–4
48
110
UNIT
V
VS
Operating supply range
2.7
5
VSENSE
Differential sense input range
TA
Ambient temperature
20
V
0
VS / G
V
–40
125
°C
6.4 Thermal Information
INA293
THERMAL METRIC(1)
DBV (SOT-23)
UNIT
5 PINS
RθJA
Junction-to-ambient thermal resistance
184.7
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
105.6
°C/W
RθJB
Junction-to-board thermal resistance
47.2
°C/W
ΨJT
Junction-to-top characterization parameter
21.5
°C/W
ΨJB
Junction-to-board characterization parameter
46.9
°C/W
RθJC(bot)
Junction-to-case (bottom) thermal resistance
N/A
°C/W
(1)
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
6.5 Electrical Characteristics
at TA = 25 °C, VS = 5 V, VSENSE = VIN+ - VIN- = 0.5 V / Gain, VCM = VIN- = 48 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
INPUT
VCM
Common-mode input range(1)
TA = -40°C to +125°C
CMRR
Common-mode rejection ratio, input
referred
-4 V ≤ VCM ≤ 110 V, TA = -40°C to +125°C
Vos
dVos/dT
Offset voltage, input referred
Offset voltage drift
–4
140
IB
Power supply rejection ratio, input
referred
Input bias current
V
160
dB
f = 50 kHz
85
dB
INA293x1
±30
±150
INA293x2
±15
±80
INA293x3
±10
±50
INA293x4
±5
±30
INA293x5
±2
±20
TA = -40℃ to +125℃, INA293x1,
INA293x2, INA293x3
±0.05
±0.5
TA = -40℃ to +125℃, INA293x4,
INA293x5
±0.025
±0.25
±1
±8
INA293x2, INA293x3, 2.7 V ≤ VS ≤ 20 V,
TA = -40°C to +125°C
±0.3
±3
INA293x4, INA293x5, 2.7 V ≤ VS ≤ 20 V,
TA = -40°C to +125°C
±0.1
±1
µV
µV/℃
INA293x1, 2.7 V ≤ VS ≤ 20 V,
TA = -40°C to +125°C
PSRR
110
µV/V
IB+, VSENSE = 0 V
10
20
30
uA
IB-, VSENSE = 0 V
10
20
30
uA
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
5
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
6.5 Electrical Characteristics (continued)
at TA = 25 °C, VS = 5 V, VSENSE = VIN+ - VIN- = 0.5 V / Gain, VCM = VIN- = 48 V (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
OUTPUT
G
Gain
INA293x1
20
V/V
INA293x2
50
V/V
INA293x3
100
V/V
INA293x4
200
V/V
INA293x5
GERR
Gain error
NLERR
Nonlinearity error
Maximum capacitive load
500
GND + 50 mV ≤ VOUT ≤ VS – 200 mV
±0.02
TA = -40°C to +125°C
±1
No sustained oscillations, no isolation
resistor
V/V
±0.15
%
±10 ppm/°C
0.01
%
500
pF
VOLTAGE OUTPUT
Swing to Vs (Power supply rail)
RLOAD = 10 kΩ, TA = -40°C to +125°C
Vs – 0.07 Vs – 0.15
Swing to ground
RLOAD = 10 kΩ, VSENSE = 0 V, TA = -40°C
to +125°C
0.005
INA293x1, CLOAD = 5 pF,
VSENSE = 200 mV
1300
INA293x2, CLOAD = 5 pF,
VSENSE = 80 mV
1300
INA293x3, CLOAD = 5 pF,
VSENSE = 40 mV
1000
INA293x4, CLOAD = 5 pF,
VSENSE = 20 mV
900
INA293x5, CLOAD = 5 pF,
VSENSE = 8 mV
900
Rising edge
2.5
VOUT = 4 V ± 0.1 V step, Output settles to
0.5%
10
VOUT = 4 V ± 0.1 V step, Output settles to
1%
5
VOUT = 4 V ± 0.1 V step, Output settles to
5%
1
0.02
V
V
FREQUENCY RESPONSE
BW
Bandwidth
SR
Slew rate
Settling time
kHz
V/µs
µs
NOISE
Ven
Voltage noise density
50
nV/√Hz
POWER SUPPLY
Vs
Supply voltage
IQ
Quiescent current
(1)
6
TA = –40°C to +125°C
2.7
1.5
TA = -40°C to +125°C
20
V
2
mA
2.25
mA
Common-mode voltage at both VIN+ and VIN- must not exceed the specified common-mode input range.
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
6.6 Typical Characteristics
72
56
40
24
8
-8
-24
-40
-56
-72
135
105
75
45
15
-15
-45
-75
-105
-135
Population
Population
All specifications at TA = 25 °C, VS = 5 V, VSENSE = VIN+ – VIN- = 0.5 V / Gain, VCM = VIN– = 48 V, unless otherwise noted.
Input Offset Voltage (PV)
Input Offset Voltage (PV)
Input Offset Voltage (PV)
27
21
15
9
3
-3
-9
-15
-21
Population
-27
45
35
25
15
5
-5
-15
-25
-35
-45
Population
Figure 6-1. INA293x1 Input Offset Production Distribution
Figure 6-2. INA293x2 Input Offset Production Distribution
Input Offset Voltage (PV)
Figure 6-3. INA293x3 Input Offset Production Distribution
Figure 6-4. INA293x4 Input Offset Production Distribution
18
14
10
6
2
-2
-6
-10
-14
-18
Population
Input Offset Voltage (PV)
16
Input Offset Voltage (PV)
Figure 6-5. INA293x5 Input Offset Production Distribution
8
0
G
G
G
G
G
-8
-16
-75
-50
-25
0
25
50
75 100
Temperature (qC)
125
=
=
=
=
=
20
50
100
200
500
150
175
Figure 6-6. Input Offset Voltage vs Temperature
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
7
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
6.6 Typical Characteristics (continued)
All specifications at TA = 25 °C, VS = 5 V, VSENSE = VIN+ – VIN- = 0.5 V / Gain, VCM = VIN– = 48 V, unless otherwise noted.
180
10
0
G
G
G
G
G
-10
-20
-75
-50
-25
0
25
50
75 100
Temperature (qC)
125
=
=
=
=
=
20
50
100
200
500
150
Common-Mode Rejection Ratio (dB)
Common-Mode Rejection Ratio (nV/V)
20
160
140
120
100
80
60
40
20
10
175
100
1k
10k
Frequency (Hz)
100k
Figure 6-8. Common-Mode Rejection Ratio vs Frequency
Figure 6-7. Common-Mode Rejection Ratio vs Temperature
0.10
60
G
G
G
G
G
50
0.05
Gain Error (%)
Gain (dB)
40
30
20
10
0
G
G
G
G
G
-10
10
=
=
=
=
=
20
50
100
200
500
100
1k
10k
100k
Frequency (Hz)
1M
-0.10
-75
10M
-50
-25
0
25
50
75 100
Temperature (qC)
125
150
175
Figure 6-10. Gain Error vs Temperature
140
0.8
0.6
0.4
0.2
0.0
-0.2
-0.4
G
G
G
G
G
-0.6
-0.8
-50
-25
0
25
50
75 100
Temperature (qC)
125
=
=
=
=
=
20
50
100
200
500
150
175
Figure 6-11. Power-Supply Rejection Ratio vs Temperature
Power-Supply Rejection Ratio (dB)
Power-Supply Rejection Ratio (PV/V)
20
50
100
200
500
-0.05
1.0
8
=
=
=
=
=
0.00
Figure 6-9. Gain vs Frequency
-1.0
-75
1M
120
100
80
60
40
20
10
100
1k
10k
Frequency (Hz)
100k
1M
Figure 6-12. Power-Supply Rejection Ratio vs Frequency
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
6.6 Typical Characteristics (continued)
25
25
20
20
Input Bias Current (PA)
Input Bias Current (PA)
All specifications at TA = 25 °C, VS = 5 V, VSENSE = VIN+ – VIN- = 0.5 V / Gain, VCM = VIN– = 48 V, unless otherwise noted.
15
VS
VS
VS
VS
10
5
=
=
=
=
5V
20V
2.7V
0V
0
-5
VS
VS
VS
VS
VS
15
10
5
0
20
40
60
80
Common-Mode Voltage (V)
100
VS = 0V and 20V, VCM = -20V
-10
-75
120
2.7 to 20V, VCM = 48V
2.7 to 20V, VCM = 120V
2.7 to 20V, VCM = -4V
0V, VCM = 120V
0V, VCM = -4V
0
-5
-10
-20
=
=
=
=
=
-50
-25
0
25
50
75 100
Temperature (qC)
125
150
175
Figure 6-14. Input Bias Current vs Temperature
VSENSE = 0 V
Figure 6-13. Input Bias Current vs Common-Mode Voltage
240
140
IB+
IBIB+, VS = 0V
IB-, VS = 0V
Input Bias Current (PA)
160
100
120
80
40
0
-40
80
60
40
20
0
-20
-80
-40
-120
-60
-160
-80
0
200
400
600
VSENSE (mV)
800
1000
Figure 6-15. INA293x1 Input Bias Current vs VSENSE
0
100
200
VSENSE (mV)
300
400
Figure 6-16. INA293x2, INA293x3 Input Bias Current vs VSENSE
100
VS
IB+, G=200
IB+, G=500
IBIB+, VS = 0V
IB-, VS = 0V
60
25qC
125qC
-40qC
VS - 1
Output Voltage (V)
80
Input Bias Current (PA)
IB+
IBIB+, VS = 0V
IB-, VS = 0V
120
Input Bias Current (PA)
200
40
20
0
VS - 2
GND + 2
GND + 1
-20
GND
0
20
40
60
VSENSE (mV)
80
100
Figure 6-17. INA293x4, INA293x5 Input Bias Current vs VSENSE
0
5
10
15
20
25
Output Current (mA)
30
35
40
VS = 2.7 V
Figure 6-18. Output Voltage vs Output Current
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
9
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
6.6 Typical Characteristics (continued)
All specifications at TA = 25 °C, VS = 5 V, VSENSE = VIN+ – VIN- = 0.5 V / Gain, VCM = VIN– = 48 V, unless otherwise noted.
VS
VS
25qC
125qC
-40qC
VS - 2
VS - 3
GND + 3
VS - 2
VS - 3
GND + 3
GND + 2
GND + 2
GND + 1
GND + 1
GND
GND
0
5
10
15
20
25
Output Current (mA)
30
35
40
0
VS = 5 V
15
20
25
Output Current (mA)
30
35
40
0.00
200
100
50
-0.10
20
10
5
Swing to VS (V)
Output Impedance (:)
10
Figure 6-20. Output Voltage vs Output Current
1000
500
2
1
0.5
0.2
0.1
0.05
-0.20
-0.30
-0.40
0.02
0.01
10
100
1k
10k
100k
Frequency (Hz)
1M
VS = 5V
VS = 20V
VS = 2.7V
-0.50
-75
10M
Figure 6-21. Output Impedance vs Frequency
-50
-25
0
25
50
75 100
Temperature (qC)
125
150
175
Figure 6-22. Swing to Supply vs Temperature
0.020
0.015
0.010
0.005
0.000
-75
-50
-25
0
25
50
75 100
Temperature (qC)
125
Figure 6-23. Swing to GND vs Temperature
150
175
Input-Referred Voltage Noise (nV/—Hz)
100
VS = 5V
VS = 20V
VS = 2.7V
Swing to GND (V)
5
VS = 20 V
Figure 6-19. Output Voltage vs Output Current
10
25qC
125qC
-40qC
VS - 1
Output Voltage (V)
Output Voltage (V)
VS - 1
G = 20
G = 500
80
70
60
50
40
30
20
10
10
100
1k
10k
Frequency (Hz)
100k
1M
Figure 6-24. Input Referred Noise vs Frequency
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
6.6 Typical Characteristics (continued)
All specifications at TA = 25 °C, VS = 5 V, VSENSE = VIN+ – VIN- = 0.5 V / Gain, VCM = VIN– = 48 V, unless otherwise noted.
2
Quiescent Current (mA)
Referred-to-Input
Voltage Noise (200 nV/div)
1.8
1.6
VS = 20V
1.4
VS = 5V
1.2
1
G = 20 to 50
G = 100 to 500
VS = 2.7V
0.8
0
Time (1 s/div)
Figure 6-25. Input Referred Noise
7.5
10
12.5
Output Voltage (V)
15
17.5
20
50
Short Circuit Current (mA)
VS = 5V
VS = 20V
VS = 2.7V
1.8
Quiescent Current (mA)
5
Figure 6-26. Quiescent Current vs Output Voltage
2
1.6
1.4
1.2
1
0.8
-75
-50
-25
0
25
50
75 100
Temperature (qC)
125
150
30
Quiescent Current (mA)
1.8
1.6
1.4
1.2
25qC
125qC
-40qC
0.8
4
6
8
10
12
14
Supply Voltage (V)
16
18
Figure 6-29. Quiescent Current vs Supply Voltage
-50
-25
0
25
50
75 100
Temperature (qC)
125
150
175
Figure 6-28. Short-Circuit Current vs Temperature
1.8
2
5V, Sourcing
5V, Sinking
20V, Sourcing
20V, Sinking
2.7V, Sourcing
2.7V, Sinking
10
2
0
=
=
=
=
=
=
20
2
1
VS
VS
VS
VS
VS
VS
40
0
-75
175
Figure 6-27. Quiescent Current vs Temperature
Quiescent Current (mA)
2.5
20
VS = 5V
VS = 20V
VS = 2.7V
1.6
1.4
1.2
1
0.8
-20
0
20
40
60
80
Common-Mode Voltage (V)
100
120
Figure 6-30. Quiescent Current vs Common-Mode Voltage
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
11
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
6.6 Typical Characteristics (continued)
0V
0V
Output Voltage
500 mV/div
0V
Input Voltage
5 mV/div
VCM
VOUT
Output Voltage (2.5V/div)
Common-Mode Voltage (20V/div)
All specifications at TA = 25 °C, VS = 5 V, VSENSE = VIN+ – VIN- = 0.5 V / Gain, VCM = VIN– = 48 V, unless otherwise noted.
0V
Time (10 Ps/div)
Time (12.5Ps/div)
Figure 6-32. INA293x3 Step Response
Figure 6-31. Common-Mode Voltage Fast Transient Pulse
Supply Voltage
Output Voltage
Voltage(1 V/div)
Voltage (1 V/div)
Supply Voltage
Output Voltage
0V
0V
Time (5 Ps/div)
Figure 6-33. Start-Up Response
12
Time (50 Ps/div)
Figure 6-34. Supply Transient Response
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
7 Detailed Description
7.1 Overview
The INA293 is a high- or low-side current-sense amplifier that offers a wide common-mode range, precision
zero-drift topology, excellent common-mode rejection ratio (CMRR), high bandwidth and fast slew rate. Different
gain versions are available to optimize the output dynamic range based on the application. The INA293 is
designed using a transconductance architecture with a current-feedback amplifier that enables low bias currents
of 20 μA with a common-mode voltage of 110 V.
7.2 Functional Block Diagram
VS
Load
Supply
ISENSE
R1
IN+
RSENSE
+
Bias
R1
IN±
Current
Feedback
OUT
-
Load
Buffer
RL
GND
7.3 Feature Description
7.3.1 Amplifier Input Common-Mode Signal
The INA293 supports large input common-mode voltages from –4 V to +110 V. Because of the internal topology,
the common-mode range is not restricted by the power-supply voltage (VS). This allows for the INA293 to be
used for both low and high side current-sensing applications.
7.3.1.1 Input-Signal Bandwidth
The INA293 –3-dB bandwidth is gain dependent, with several gain options of 20 V/V, 50 V/V, 100 V/V, 200 V/V,
and 500 V/V. The unique multistage design enables the amplifier to achieve high bandwidth at all gains. This
high bandwidth provides the throughput and fast response that is required for the rapid detection and processing
of overcurrent events.
The bandwidth of the device also depends on the applied VSENSE voltage. Figure 7-1 shows the bandwidth
performance profile of the device over frequency as output voltage increases for each gain variation. As shown
in Figure 7-1, the device exhibits the highest bandwidth with higher VSENSE voltages, and the bandwidth is
higher with lower device gain options. Individual requirements determine the acceptable limits of error for high
frequency current-sensing applications. Testing and evaluation in the end application or circuit is required to
determine the acceptance criteria, and to validate that the performance levels meet the system specifications.
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
13
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
1400
Bandwidth (kHz)
1200
1000
800
600
INA293A1
INA293A2
INA293A3
INA293A4
INA293A5
400
200
0
1
2
3
Output Voltage (V)
Figure 7-1. Bandwidth vs Output Voltage
7.3.1.2 Low Input Bias Current
The INA293 inputs draw a 20-µA (typical) bias current at a common-mode voltage as high as 110 V, which
enables precision current sensing on applications that require lower current leakage.
7.3.1.3 Low VSENSE Operation
The INA293 operates with high performance across the entire valid VSENSE range. The zero-drift input
architecture of the INA293 provides the low offset voltage and low offset drift needed to measure low VSENSE
levels accurately across the wide operating temperature of –40 °C to +125 °C. Low VSENSE operation is
particularly beneficial when using low ohmic shunts for low current measurements, as power losses across
the shunt are significantly reduced.
7.3.1.4 Wide Fixed Gain Output
The INA293 gain error is < 0.15% at room temperature, with a maximum drift of 10 ppm/°C over the full
temperature range of –40°C to +125°C. The INA293 is available in multiple gain options of 20 V/V, 50 V/V, 100
V/V, 200 V/V, and 500 V/V, which the system designer should select based on their desired signal-to-noise ratio
and other system requirements.
The INA293 closed-loop gain is set by a precision, low drift internal resistor network. The ratio of these resistors
are excellently matched, while the absolute values may vary significantly. Adding additional resistance around
the INA293 to change the effective gain is not recommended, however, because of this variation. The typical
values of the gain resistors are described in Table 7-1.
Table 7-1. Fixed Gain Resistor
GAIN
R1
RL
20 (V/V)
25 kΩ
500 kΩ
50 (V/V)
10 kΩ
500 kΩ
100 (V/V)
10 kΩ
1000 kΩ
200 (V/V)
5 kΩ
1000 kΩ
500 (V/V)
2 kΩ
1000 kΩ
7.3.1.5 Wide Supply Range
The INA293 operates with a wide supply range from 2.7 V to 20 V. The output stage supports a wide output
range while INA293x1 (gain of 20 V/V) at a supply voltage of 20 V allows a maximum acceptable differential
input of 1 V. When paired with the small input offset voltage of the INA293, systems with very wide dynamic
range of current measurement can be supported.
14
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
7.4 Device Functional Modes
7.4.1 Unidirectional Operation
The INA293 measures the differential voltage developed by current flowing through a resistor, commonly
referred to as a current-sensing resistor or a current-shunt resistor. The INA293 operates in unidirectional mode
only, meaning it only senses current sourced from a power supply to a system load as shown in Figure 7-2.
5V
48-V
Supply
ISENSE
R1
IN+
+
RSENSE
Bias
R1
Current
Feedback
OUT
-
IN±
Buffer
RL
Load
GND
Figure 7-2. Unidirectional Application
The linear range of the output stage is limited to how close the output voltage can approach ground under
zero-input conditions. The zero current output voltage of the INA293 is very small, with a maximum of GND + 20
mV. Make sure to apply a differential input voltage of (20 mV / Gain) or greater to keep the INA293 output in the
linear region of operation.
7.4.2 High Signal Throughput
With a bandwidth of 1.3 MHz at a gain of 20 V/V and a slew rate of 2.5 V/µs, the INA293 is specifically designed
for detecting and protecting applications from fast inrush currents. As shown in Table 7-2, the INA293 responds
in less than 2 µs for a system measuring a 75-A threshold on a 2-mΩ shunt.
Table 7-2. Response Time
PARAMETER
EQUATION
INA293
AT VS = 5 V
G
Gain
20 V/V
IMAX
Maximum current
100 A
IThreshold
Threshold current
75 A
RSENSE
Current sense resistor value
2 mΩ
VOUT_MAX
Output voltage at maximum current
VOUT_MAX = IMAX × RSENSE × G
4V
VOUT_THR
Output voltage at threshold current
VOUT_THR = ITHR × RSENSE × G
3V
SR
Slew rate
Output response time
2.5 V/µs
Tresponse= VOUT_THR / SR
< 2 µs
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
15
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
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, as well as validating and testing their design
implementation to confirm system functionality.
8.1 Application Information
The INA293 amplifies the voltage developed across a current-sensing resistor as current flows through
the resistor to the load. The wide input common-mode voltage range and high common-mode rejection of
the INA293 make it usable over a wide range of voltage rails while still maintaining an accurate current
measurement.
8.1.1 RSENSE and Device Gain Selection
The accuracy of any current-sense amplifier is maximized by choosing the current-sense resistor to be as large
as possible. A large sense resistor maximizes the differential input signal for a given amount of current flow
and reduces the error contribution of the offset voltage. However, there are practical limits as to how large the
current-sense resistor can be in a given application because of the resistor size and maximum allowable power
dissipation. Equation 1 gives the maximum value for the current-sense resistor for a given power dissipation
budget:
RSENSE
PDMAX
IMAX2
(1)
where:
•
•
PDMAX is the maximum allowable power dissipation in RSENSE.
IMAX is the maximum current that will flow through RSENSE.
An additional limitation on the size of the current-sense resistor and device gain is due to the power-supply
voltage, VS, and device swing-to-rail limitations. To make sure that the current-sense signal is properly passed
to the output, both positive and negative output swing limitations must be examined. Equation 2 provides the
maximum values of RSENSE and GAIN to keep the device from exceeding the positive swing limitation.
IMAX ª RSENSE ª *$,1 < VSP
(2)
where:
•
•
•
IMAX is the maximum current that will flow through RSENSE.
GAIN is the gain of the current-sense amplifier.
VSP is the positive output swing as specified in the data sheet.
To avoid positive output swing limitations when selecting the value of RSENSE, there is always a trade-off
between the value of the sense resistor and the gain of the device under consideration. If the sense resistor
selected for the maximum power dissipation is too large, then it is possible to select a lower-gain device in order
to avoid positive swing limitations.
The negative swing limitation places a limit on how small the sense resistor value can be for a given application.
Equation 3 provides the limit on the minimum value of the sense resistor.
IMIN ª RSENSE ª *$,1 > VSN
(3)
where:
•
16
IMIN is the minimum current that will flow through RSENSE.
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
INA293
www.ti.com
•
•
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
GAIN is the gain of the current-sense amplifier.
VSN is the negative output swing of the device.
Table 8-1 shows an example of the different results obtained from using five different gain versions of the
INA293. From the table data, the highest gain device allows a smaller current-shunt resistor and decreased
power dissipation in the element.
Table 8-1. RSENSE Selection and Power Dissipation(1)
RESULTS AT VS = 5 V
PARAMETER
EQUATION
A1, B1
DEVICES
G
Gain
VDIFF
Ideal differential input voltage
VDIFF = VOUT / G
RSENSE
Current sense resistor value
RSENSE = VDIFF / IMAX
PSENSE
Current-sense resistor power dissipation
RSENSE × IMAX2
(1)
A2, B2
DEVICES
A3, B3
DEVICES
A4, B4
DEVICES
A5, B5
DEVICES
20 V/V
50 V/V
100 V/V
200 V/V
500 V/V
250 mV
100 mV
50 mV
25 mV
10 mV
25 mΩ
10 mΩ
5 mΩ
2.5 mΩ
1 mΩ
2.5 W
1W
0.5W
0.25 W
0.1 W
Design example with 10-A full-scale current with maximum output voltage set to 5 V.
8.1.2 Input Filtering
Note
Input filters are not required for accurate measurements using the INA293, and use of filters in this
location is not recommended. If filter components are used on the input of the amplifier, follow the
guidelines in this section to minimize the effects on performance.
Based strictly on user design requirements, external filtering of the current signal may be desired. The initial
location that can be considered for the filter is at the output of the current sense amplifier. Although placing the
filter at the output satisfies the filtering requirements, this location changes the low output impedance measured
by any circuitry connected to the output voltage pin. The other location for filter placement is at the current
sense amplifier input pins. This location satisfies the filtering requirement also, however the components must be
carefully selected to minimally impact device performance. Figure 8-1 shows a filter placed at the input pins.
VS
VCM
ISENSE
RIN
R1
IN+
+
CIN
RSENSE
Bias
RIN
R1
IN±
Current
Feedback
OUT
-
Load
Buffer
RL
GND
Figure 8-1. Filter at Input Pins
External series resistance provides a source of additional measurement error, so keep the value of these
series resistors to 10 Ω or less to reduce loss of accuracy. The internal bias network shown in Figure 8-1
creates a mismatch in input bias currents (see Figure 6-15, Figure 6-16 and Figure 6-17) when a differential
voltage is applied between the input pins. If additional external series filter resistors are added to the circuit, a
mismatch is created in the voltage drop across the filter resistors. This voltage is a differential error voltage in the
shunt resistor voltage. In addition to the absolute resistor value, mismatch resulting from resistor tolerance can
significantly impact the error because this value is calculated based on the actual measured resistance.
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
17
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
The measurement error expected from the additional external filter resistors can be calculated using Equation 4,
where the gain error factor is calculated using Equation 5.
Gain Error (%) = 100 - (100 ´ Gain Error Factor)
(4)
The gain error factor, shown in Equation 4, can be calculated to determine the gain error introduced by the
additional external series resistance. Equation 4 calculates the deviation of the shunt voltage, resulting from
the attenuation and imbalance created by the added external filter resistance. Table 8-2 provides the gain error
factor and gain error for several resistor values.
Gain Error Factor =
4000 ª 51
(4000 ª 51 + 4000 ª 5S + RS ª 51)
(5)
Where:
•
•
RS is the external filter resistance value
R1 is the INA293 input resistance value specified in Table 7-1
Table 8-2. Example Gain Error Factor and Gain Error for 10-Ω External Filter Input Resistors
DEVICE (GAIN)
GAIN ERROR FACTOR
GAIN ERROR (%)
INA293x1 (20)
0.997108386
-0.289161432
INA293x2 (50)
0.996512207
-0.348779273
INA293x3 (100)
0.996512207
-0.348779273
INA293x4 (200)
0.995520159
-0.447984072
INA293x5 (500)
0.992555831
-0.744416873
8.2 Typical Application
The INA293 is a unidirectional, current-sense amplifier capable of measuring currents through a resistive shunt
with shunt common-mode voltages from –4 V to +110 V.
24 V
Solenoid
RSENSE
ISENSE
MCU
±
+
ADC
INA
5V
GND
Figure 8-2. Current Sensing in a Solenoid Application
8.2.1 Design Requirements
In this example application, the common-mode voltage ranges from 0 V to 24 V. The maximum sense current is
1.5 A, and a 5-V supply is available for the INA293. Following the design guidelines from the RSENSE and Device
Gain Selection section, a RSENSE of 50 mΩ and a gain of 50 V/V are selected to provide good output dynamic
range. Table 8-3 lists the design setup for this application.
Table 8-3. Design Parameters
18
DESIGN PARAMETERS
EXAMPLE VALUE
Power supply voltage
5V
Common-mode voltage range
0 V to 24 V
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
Table 8-3. Design Parameters (continued)
DESIGN PARAMETERS
EXAMPLE VALUE
Maximum sense current
1.5 A
RSENSE resistor
50 mΩ
Gain option
50 V/V
8.2.2 Detailed Design Procedure
The INA293 is designed to measure current in a typical solenoid application. The INA293 measures current
across the 50-mΩ shunt that is placed at the output of the half-bridge. The INA293 measures the differential
voltage across the shunt resistor, and the signal is internally amplified with a gain of 50 V/V. The output of the
INA293 is connected to the analog-to-digital converter (ADC) of an MCU to digitize the current measurements.
Solenoid loads are highly inductive and are often prone to failure. Solenoids are often used for position control,
precise fluid control, and fluid regulation. Measuring real-time current on the solenoid continuously can indicate
premature failure of the solenoid which can lead to a faulty control loop in the system. Measuring high-side
current also indicates if there are any ground faults on the solenoid or the FETs that can be damaged in an
application. The INA293, with high bandwidth and slew rate, can be used to detect fast overcurrent conditions to
prevent the solenoid damage from short-to-ground faults.
8.2.2.1 Overload Recovery With Negative VSENSE
The INA293 is a unidirectional current sense amplifier that is meant to operate with a positive differential input
voltage (VSENSE). If negative VSENSE is applied, the device is placed in an overload condition and requires time
to recover once VSENSE returns positive. The required overload recovery time increases with more negative
VSENSE.
8.2.3 Application Curve
6
VCM
VOUT
4
Common-Mode Input Voltage, VCM (V)
2
40
0
Output Voltage, VOUT (V)
Figure 8-3 shows the output response of a solenoid.
30
20
10
0
Time (50 ms/div)
Figure 8-3. Solenoid Control Current Response
9 Power Supply Recommendations
The INA293 power supply can be 5 V, whereas the input common-mode voltage can vary between –4 V to 110
V. The output voltage range of the OUT pin, however, is limited by the voltage on the power-supply pin.
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
19
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
10 Layout
10.1 Layout Guidelines
Attention to good layout practices is always recommended.
•
•
Connect the input pins to the sensing resistor using a Kelvin or 4-wire connection. This connection technique
makes sure that only the current-sensing resistor impedance is detected between the input pins. Poor routing
of the current-sensing resistor commonly results in additional resistance present between the input pins.
Given the very low ohmic value of the current resistor, any additional high-current carrying impedance can
cause significant measurement errors.
Place the power-supply bypass capacitor as close as possible to the device power supply and ground pins.
The recommended value of this bypass capacitor is 0.1 µF. Additional decoupling capacitance can be added
to compensate for noisy or high-impedance power supplies.
10.2 Layout Example
OUT
Supply
Voltage
Vs
Bypass
Cap
Via to GND Plane
GND
Ground Plane
IN +
IN -
Figure 10-1. INA293A Recommended Layout
OUT
IN -
Via to GND Plane
GND
Supply
Voltage
Vs
IN +
Bypass
Cap
Ground Plane
Figure 10-2. INA293B Recommended Layout
20
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
INA293
www.ti.com
SBOS470A – DECEMBER 2019 – REVISED JUNE 2021
11 Device and Documentation Support
11.1 Documentation Support
11.1.1 Related Documentation
For related documentation see the following: Texas Instruments, INA293EVM user's guide
11.2 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. Click on
Subscribe to updates 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 Support Resources
TI E2E™ support forums are an engineer's go-to source for fast, verified answers and design help — straight
from the experts. Search existing answers or ask your own question to get the quick design help you need.
Linked content is 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.
11.4 Trademarks
TI E2E™ is a trademark of Texas Instruments.
All 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
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.
Submit Document Feedback
Copyright © 2021 Texas Instruments Incorporated
Product Folder Links: INA293
21
PACKAGE OPTION ADDENDUM
www.ti.com
7-May-2021
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)
INA293A1IDBVR
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1XWC
INA293A1IDBVT
ACTIVE
SOT-23
DBV
5
250
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1XWC
INA293A2IDBVR
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1XXC
INA293A2IDBVT
ACTIVE
SOT-23
DBV
5
250
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1XXC
INA293A3IDBVR
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1XZC
INA293A3IDBVT
ACTIVE
SOT-23
DBV
5
250
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1XZC
INA293A4IDBVR
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1Z1C
INA293A4IDBVT
ACTIVE
SOT-23
DBV
5
250
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1Z1C
INA293A5IDBVR
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1Z7C
INA293A5IDBVT
ACTIVE
SOT-23
DBV
5
250
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1Z7C
INA293B1IDBVR
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1Z2C
INA293B1IDBVT
ACTIVE
SOT-23
DBV
5
250
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1Z2C
INA293B2IDBVR
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1Z3C
INA293B2IDBVT
ACTIVE
SOT-23
DBV
5
250
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1Z3C
INA293B3IDBVR
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1Z4C
INA293B3IDBVT
ACTIVE
SOT-23
DBV
5
250
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1Z4C
INA293B4IDBVR
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1Z5C
INA293B4IDBVT
ACTIVE
SOT-23
DBV
5
250
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1Z5C
INA293B5IDBVR
ACTIVE
SOT-23
DBV
5
3000
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1Z6C
INA293B5IDBVT
ACTIVE
SOT-23
DBV
5
250
RoHS & Green
NIPDAU
Level-1-260C-UNLIM
-40 to 125
1Z6C
Addendum-Page 1
Samples
PACKAGE OPTION ADDENDUM
www.ti.com
7-May-2021
(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
工商网监
湘ICP备2023018690号
