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OPA2172-Q1, OPA4172-Q1
SBOS809A – NOVEMBER 2016 – REVISED JUNE 2017
OPAx172-Q1 36-V, Single-Supply, 10-MHz, Rail-to-Rail Output Automotive Grade
Operational Amplifiers
1 Features
3 Description
•
•
The OPA2172-Q1 and OPA4172-Q1 (OPAx172-Q1)
are a family of 36-V, single-supply, low-noise
operational amplifiers capable of operating on
supplies ranging from 4.5 V (±2.25 V) to 36 V
(±18 V). The OPAx172-Q1 are available in
micropackages, and offer low offset, drift, and
quiescent current. These devices also offer wide
bandwidth, fast slew rate, and high output current
drive capability. The dual and quad versions all have
identical specifications for maximum design flexibility.
1
•
•
•
•
•
•
•
•
•
•
•
•
•
Qualified for Automotive Applications
AEC-Q100 Qualified With the Following Results:
– Device Temperature Grade 1:
–40°C to +125°C
Ambient Operating Temperature Range
– Device HBM ESD Classification Level 3A
– Device CDM ESD Classification level C6
Wide Supply Range:
4.5 V to 36 V, ±2.25 V to ±18 V
Low Offset Voltage: ±0.2 mV
Low Offset Drift: ±0.3 µV/°C
Gain Bandwidth: 10 MHz
Low Input Bias Current: ±8 pA
Low Quiescent Current: 1.6 mA per Amplifier
Low Noise: 7 nV/√Hz
EMI and RFI Filtered Inputs
Input Range Includes the Negative Supply
Input Range Operates to Positive Supply
Rail-to-Rail Output
High Common-Mode Rejection: 120 dB
Industry-Standard Packages:
– VSSOP-8, TSSOP-14
Automotive
HEV and EV Power Trains
Advanced Driver Assist (ADAS)
Automatic Climate Controls
Avionics, Landing Gear
Medical Instrumentation
Current Sense
Superior THD Performance
Total Harmonic Distortion + Noise (%)
PART NUMBER
PACKAGE
BODY SIZE (NOM)
OPA2172-Q1
VSSOP (8)
3.00 mm × 3.00 mm
OPA4172-Q1
TSSOP (14)
5.00 mm × 4.40 mm
VCC
G = +1 V/V, RL = 10 k
G = +1 V/V, RL = 2 k
G = +1 V/V, RL = 600
G = -1 V/V, RL = 10 k
-100
G = -1 V/V, RL = 2 k
G = -1 V/V, RL = 600
0.0001
-120
VOUT = 3.5 VRMS
BW = 80 kHz
0.00001
-140
10
Device Information(1)
JFET-Input Low-Noise Amplifier
-80
Total Harmonic Distortion + Noise (dB)
0.01
0.001
The OPAx172-Q1 series of op amps are specified
from –40°C to +125°C.
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
2 Applications
•
•
•
•
•
•
•
Unlike most op amps that are specified at only one
supply voltage, the OPAx172-Q1 family is specified
from 4.5 V to 36 V. Input signals beyond the supply
rails do not cause phase reversal. The input can
operate 100 mV below the negative rail and within 2
V of the top rail during normal operation. Note that
these devices can operate with full rail-to-rail input
100 mV beyond the top rail, but with reduced
performance within 2 V of the top rail.
100
1k
Frequency (Hz)
10k
C007
VCC
V1
15 V
VEE
V2
15 V
R1
3.9 kŸ
R2
3.9 kŸ
VEE
VOUT
++
LSK489
Q1
R3
1.13 kŸ
VCC
Q2
VCC
R6
27.4 kŸ
Q3
R4
11.5 Ÿ
MMBT4401
Q4
MMBT4401
R5
300 Ÿ
Copyright © 2016, Texas
Instruments Incorporated
VEE
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.
OPA2172-Q1, OPA4172-Q1
SBOS809A – NOVEMBER 2016 – REVISED JUNE 2017
www.ti.com
Table of Contents
1
2
3
4
5
6
7
8
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Device Comparison Table.....................................
Pin Configuration and Functions .........................
Specifications.........................................................
1
1
1
2
3
3
4
7.1
7.2
7.3
7.4
7.5
7.6
4
4
4
4
5
7
Absolute Maximum Ratings ......................................
ESD Ratings..............................................................
Recommended Operating Conditions.......................
Thermal Information ..................................................
Electrical Characteristics...........................................
Typical Characteristics ..............................................
Detailed Description ............................................ 14
8.1
8.2
8.3
8.4
Overview .................................................................
Functional Block Diagram .......................................
Feature Description.................................................
Device Functional Modes........................................
14
14
15
17
9
Applications and Implementation ...................... 20
9.1 Application Information............................................ 20
9.2 Typical Applications ................................................ 20
10 Power Supply Recommendations ..................... 24
11 Layout................................................................... 24
11.1 Layout Guidelines ................................................. 24
11.2 Layout Example .................................................... 25
12 Device and Documentation Support ................. 26
12.1
12.2
12.3
12.4
12.5
12.6
12.7
12.8
Device Support......................................................
Documentation Support ........................................
Related Links ........................................................
Receiving Notification of Documentation Updates
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
26
26
26
26
27
27
27
27
13 Mechanical, Packaging, and Orderable
Information ........................................................... 27
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Original (November 2016) to Revision A
Page
•
Deleted OPA172-Q1 throughout data sheet........................................................................................................................... 1
•
Deleted Operating temperature, TA from Absolute Maximum Ratings ................................................................................... 4
•
Added OPA4172-Q1 in PW package to ESD Ratings table................................................................................................... 4
•
Changed values in the Thermal Information table to align with JEDEC standards. .............................................................. 4
•
Deleted value: ±14 and temperature range: TA = –40°C to +125°C from Input bias current and added TA = 25°C to
Input bias current and Input offset current.............................................................................................................................. 5
•
Changed TYP value from: 2.5 to: 2 for Input voltage noise, En ............................................................................................. 5
•
Deleted Specified temperature from Electrical Characteristics table ..................................................................................... 6
•
Changed figure: Operational Amplifier Board Layout for a Noninverting Configuration with revised content...................... 25
2
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SBOS809A – NOVEMBER 2016 – REVISED JUNE 2017
5 Device Comparison Table
Table 1. Device Comparison
DEVICE
PACKAGE
OPA2172-Q1 (dual)
VSSOP-8
OPA4172-Q1 (quad)
TSSOP-14
Table 2. Device Family Comparison
DEVICE
QUIESCENT CURRENT
(IQ)
GAIN BANDWIDTH PRODUCT
(GBP)
VOLTAGE NOISE DENSITY
(en)
OPAx172
1600 µA
10 MHz
7 nV/√Hz
OPAx171
475 µA
3.0 MHz
14 nV/√Hz
OPAx170
110 µA
1.2 MHz
19 nV/√Hz
6 Pin Configuration and Functions
OPA2172-Q1 DGK Package
8-Pin VSSOP
Top View
OUT A
1
8
V+
-IN A
2
7
+IN A
3
V-
4
OPA4172-Q1 PW Package
14-Pin TSSOP
Top View
OUT A
1
14
OUT D
OUT B
-IN A
2
13
-IN D
6
-IN B
+IN A
3
12
+IN D
5
+IN B
V+
4
11
V-
+IN B
5
10
+IN C
-IN B
6
9
-IN C
OUT B
7
8
OUT C
Pin Functions
PIN
OPA2172-Q1
OPA4172-Q1
DGK (VSSOP)
PW (TSSOP)
2
2
I
Inverting input, channel A
–IN B
6
6
I
Inverting input, channel B
–IN C
—
9
I
Inverting input,,channel C
–IN D
—
13
I
Inverting input, channel D
+IN A
3
3
I
Noninverting input, channel A
+IN B
5
5
I
Noninverting input, channel B
+IN C
—
10
I
Noninverting input, channel C
+IN D
—
12
I
Noninverting input, channel D
OUT A
1
1
O
Output, channel A
OUT B
7
7
O
Output, channel B
OUT C
—
8
O
Output, channel C
OUT D
—
14
O
Output, channel D
V–
4
11
—
Negative (lowest) power supply
V+
8
4
—
Positive (highest) power supply
NAME
–IN A
I/O
DESCRIPTION
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OPA2172-Q1, OPA4172-Q1
SBOS809A – NOVEMBER 2016 – REVISED JUNE 2017
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7 Specifications
7.1 Absolute Maximum Ratings
over operating free-air temperature range (unless otherwise noted) (1)
MIN
MAX
–20
20
(V–) – 0.5
(V+) + 0.5
–0.5
0.5
–10
10
Supply voltage, V+ to V–
Single-supply voltage
Voltage
40
Signal input pins voltage
Differential (3)
Output short-circuit (4)
Temperature
(2)
(3)
(4)
(2)
Signal input pins current
Current
(1)
Common-mode
UNIT
V
mA
Continuous
Junction, TJ
150
Storage, Tstg
–65
150
°C
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.
Transient conditions that exceed these voltage ratings must be current limited to 10 mA or less.
Refer to the Electrical Overstress section for more information.
Short-circuit to ground, one amplifier per package.
7.2 ESD Ratings
VALUE
UNIT
OPA2172-Q1 in DGK package
V(ESD)
Electrostatic discharge
Human-body model (HBM), per AEC Q100-002 (1)
±4000
Charged-device model (CDM), per AEC Q100-011
±1000
Human-body model (HBM), per AEC Q100-002 (1)
±4000
Charged-device model (CDM), per AEC Q100-011
±750
V
OPA4172-Q1 in PW package
V(ESD)
(1)
Electrostatic discharge
V
AEC Q100-002 indicates that HBM stressing shall be in accordance with the ANSI/ESDA/JEDEC JS-001 specification.
7.3 Recommended Operating Conditions
over operating free-air temperature range (unless otherwise noted)
MIN
MAX
4.5
36
±2.25
±18
–40
125
Single-supply
Supply voltage, (V+) – (V–)
Dual-supply
Specified temperature
UNIT
V
°C
7.4 Thermal Information
THERMAL METRIC
(1)
OPA2172-Q1
OPA4172-Q1
DGK (VSSOP)
PW (TSSOP)
8 PINS
14 PINS
181.4
107.5
°C/W
UNIT
RθJA
Junction-to-ambient thermal resistance
RθJC(top)
Junction-to-case (top) thermal resistance
69.2
32.5
°C/W
RθJB
Junction-to-board thermal resistance
103.3
50.4
°C/W
ψJT
Junction-to-top characterization parameter
10.9
1.8
°C/W
ψJB
Junction-to-board characterization parameter
101.6
49.6
°C/W
RθJC(bot)
Junction-to-case (bottom) thermal resistance
N/A
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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SBOS809A – NOVEMBER 2016 – REVISED JUNE 2017
7.5 Electrical Characteristics
at TA = 25°C, VS = ±2.25 V to ±18 V, VCM = VOUT = VS / 2, and RL = 10 kΩ connected to VS / 2 (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
OFFSET VOLTAGE
±0.2
VOS
Input offset voltage
dVOS/dT
Input offset voltage drift
TA = –40°C to +125°C
PSRR
Power-supply rejection ratio
TA = –40°C to +125°C
Channel separation, dc
At dc
TA = –40°C to +125°C
±1
mV
±1.15
OPA4172-Q1
±0.3
OPA2172-Q1
±1.5
µV/°C
±1.8
±1
±3
µV/V
5
µV/V
INPUT BIAS CURRENT
TA = 25°C
IB
Input bias current
TA = –40°C to +125°C
±8
OPA2172-Q1IDGK
OPA4172-Q11PW
TA = 25°C
IOS
Input offset current
TA = –40°C to +125°C
±2
±15
pA
±18
nA
±15
pA
OPA4172-Q1
±1
OPA2172-Q1
±3
nA
NOISE
En
Input voltage noise
en
Input voltage noise density
in
Input current noise density
f = 0.1 Hz to 10 Hz
2
f = 100 Hz
µVPP
12
f = 1 kHz
7
f = 1 kHz
1.6
nV/√Hz
fA/√Hz
INPUT VOLTAGE
Common-mode voltage (1)
VCM
CMRR
Common-mode rejection ratio
(V–) – 0.1 V
VS = ±2.25 V, (V–) – 0.1 V < VCM < (V+) – 2 V,
TA = –40°C to +125°C
VS = ±18 V, (V–) – 0.1 V < VCM < (V+) – 2 V,
TA = –40°C to +125°C
(V+) – 2 V
90
104
110
120
V
dB
INPUT IMPEDANCE
Differential
100 || 4
Common-mode
6 || 4
MΩ || pF
1013Ω || pF
OPEN-LOOP GAIN
AOL
Open-loop voltage gain
(V–) + 0.35 V < VO < (V+) – 0.35 V, OPA4172-Q1
RL = 10 kΩ, TA = –40°C to +125°C OPA2172-Q1
(V–) + 0.5 V < VO < (V+) – 0.5 V,
RL = 2 kΩ, TA = –40°C to +125°C
110
130
107
115
OPA4172-Q1
116
OPA2172-Q1
107
dB
FREQUENCY RESPONSE
GBP
Gain bandwidth product
SR
Slew rate
tS
Settling time
THD+N
(1)
G=1
To 0.1%, VS = ±18 V, G = 1, 10-V step
10
MHz
10
V/µs
2
To 0.01% (12 bit), VS = ±18 V, G = 1, 10-V step
3.2
Overload recovery time
VIN × Gain > VS
200
Total harmonic distortion +
noise
VS = 36 V, G = 1, f = 1 kHz, VO = 3.5 VRMS
µs
ns
0.00005%
The input range can be extended beyond (V+) – 2 V up to (V+) + 0.1 V. See the Typical Characteristics and Application Information
sections for additional information.
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Electrical Characteristics (continued)
at TA = 25°C, VS = ±2.25 V to ±18 V, VCM = VOUT = VS / 2, and RL = 10 kΩ connected to VS / 2 (unless otherwise noted)
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
OUTPUT
VS = +36 V
VS = +36 V,
TA = –40°C to +125°C
VO
Voltage output swing from rail
VS = 4.5 V
VS = 4.5 V,
TA = –40°C to +125°C
ISC
Short-circuit current
CLOAD
Capacitive load drive
ZO
Open-loop output impedance
RL = 10 kΩ
70
90
RL = 2 kΩ
330
400
RL = 10 kΩ
95
120
RL = 2 kΩ
470
530
RL = 10 kΩ
10
20
RL = 2 kΩ
40
50
RL = 10 kΩ
10
25
55
70
RL = 2 kΩ
±75
mA
See the Typical Characteristics
f = 1 MHz, IO = 0 A
mV
pF
60
Ω
POWER SUPPLY
VS
Specified voltage
IQ
Quiescent current per
amplifier
6
4.5
IO = 0 A
IO = 0 A, TA = –40°C to +125°C
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36
1.6
1.8
2
V
mA
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SBOS809A – NOVEMBER 2016 – REVISED JUNE 2017
7.6 Typical Characteristics
at VS = ±18 V, VCM = VS / 2, RLOAD = 10 kΩ connected to VS / 2, and CL = 100 pF (unless otherwise noted)
25
Distribution Taken From 47 Amplifiers
Offset Voltage Drift (µV/ƒC)
Offset Voltage (mV)
C013
C013
Figure 1. Offset Voltage Production Distribution
Figure 2. Offset Voltage Drift Production Distribution
250
225
5 Typical Units Shown
VS = ±18 V
200
100
VOS ( V)
0
±50
VCM =16V
VCM = -18.1V
75
50
VOS ( V)
5 Typical Units Shown
VS = ±18 V
150
150
0
±75
±100
±150
±150
±200
±250
±75
±50
±25
±225
0
25
50
75
100
125
Temperature (ƒC)
150
±20
±15
±10
0
±5
5
10
15
VCM (V)
C001
Figure 3. Offset Voltage vs Temperature
(VS = ±18 V)
20
C001
Figure 4. Offset Voltage vs Common-Mode Voltage
(VS = ±18 V)
500
20
5 Typical Units Shown
VS = ±18 V
10
400
Vs = ±2.25V
300
0
5 Typical Units Shown
VS = ±2.25V to “18V
200
VOS ( V)
VOS (mV)
1.00
0.90
0.80
0.70
0.60
0.50
0.40
5
0
1.00
0.80
0.60
0.40
0.20
0.00
-0.20
-0.40
-0.60
0
-0.80
5
10
0.30
10
15
0.20
15
Temperature = -40ƒC to 125ƒC
20
0.10
20
0.00
Percentage of Amplifiers (%)
Distribution Taken From 5185 Amplifiers
-1.00
Percentage of Amplifiers (%)
25
-10
-20
100
0
±100
±200
-30
±300
-40
±400
±500
-50
14
15
16
17
VCM (V)
18
0.0
2.0
4.0
Figure 5. Offset Voltage vs Common-Mode Voltage
(Upper Stage)
6.0
8.0
10.0 12.0 14.0 16.0 18.0
VSUPPLY (V)
C001
C001
Figure 6. Offset Voltage vs Power Supply
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Typical Characteristics (continued)
at VS = ±18 V, VCM = VS / 2, RLOAD = 10 kΩ connected to VS / 2, and CL = 100 pF (unless otherwise noted)
12
8000
8
6
IbN
4
2
0
±2
6000
Input Bias Current (pA)
Input Bias Current (pA)
IB+
IB Ios
IbP
10
4000
2000
0
Ios
TA = 25°C
±4
±18.0 ±13.5
±2000
±9.0
0.0
±4.5
4.5
9.0
13.5
VCM (V)
±50
18.0
50
75
100
125
150
C001
Figure 8. Input Bias Current vs Temperature
Common-Mode Rejection Ratio (dB),
Power-Supply Rejection Ratio (dB)
Output Voltage (V)
25
160.0
(V+) +1
(V+)
(V+) -1
(V+) -2
(V+) -3
(V+) -4
(V+) -5
(V-) +5
(V-) +4
(V-) +3
(V-) +2
(V-) +1
(V-)
(V-) -1
25ƒC
±40ƒC
125ƒC
85ƒC
85ƒC
125ƒC
±40ƒC
25ƒC
140.0
120.0
100.0
80.0
60.0
+PSRR
40.0
-PSRR
20.0
CMRR
0.0
0
10
20
30
40
50
60
70
80
90
Output Current (mA)
100
1
10
100
1k
10k
100k
Frequency (Hz)
C011
Figure 9. Output Voltage Swing vs Output Current
(Maximum Supply)
1M
C012
Figure 10. CMRR and PSRR vs Frequency
(Referred-to-Input)
30
10
20
9 ” 9CM ”
VS = ±2.25V, -
Power-Supply Rejection Ratio (µV/V)
Common-Mode Rejection Ratio (µV/V)
0
Temperature (ƒC)
Figure 7. Input Bias Current vs Common-Mode Voltage
9
10
0
VS = “18 V, -
9 ” 9CM ”
9
±10
8
6
4
2
0
±2
±75
±50
±25
0
25
50
75
100
Temperature (ƒC)
Figure 11. CMRR vs Temperature
8
±25
C001
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125
150
±75
±50
±25
0
25
50
75
100
Temperature (ƒC)
C001
125
150
C001
Figure 12. PSRR vs Temperature
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SBOS809A – NOVEMBER 2016 – REVISED JUNE 2017
Typical Characteristics (continued)
500 nV/div
Noise Spectral Density (nV/rtHz)
at VS = ±18 V, VCM = VS / 2, RLOAD = 10 kΩ connected to VS / 2, and CL = 100 pF (unless otherwise noted)
100
10
Peak-to-Peak Noise = 2 Vpp
1
Time (1 s/div)
1
10
100
Figure 13. 0.1-Hz to 10-Hz Noise
G = -1 V/V, RL = 10 k
-100
G = -1 V/V, RL = 2 k
G = -1 V/V, RL = 600
0.0001
-120
VOUT = 3.5 VRMS
BW = 80 kHz
0.00001
-140
1k
10k
Frequency (Hz)
0.1
Total Harmonic Distortion + Noise (%)
Total Harmonic Distortion + Noise (%)
G = +1 V/V, RL = 600
100
100k
C001
-60
G = +1 V/V, RL = 10 k
G = +1 V/V, RL = 2 k
G = +1 V/V, RL = 600
G = -1 V/V, RL = 10 k
G = -1 V/V, RL = 2 k
G = -1 V/V, RL = 600
0.01
-80
0.001
-100
0.0001
-120
f = 1 kHz
BW = 80 kHz
0.00001
0.01
-140
0.1
1
10
Output Amplitude (VRMS)
C007
Figure 15. THD+N Ratio vs Frequency
Total Harmonic Distortion + Noise (dB)
G = +1 V/V, RL = 2 k
Total Harmonic Distortion + Noise (dB)
-80
G = +1 V/V, RL = 10 k
10
10k
Figure 14. Input Voltage Noise Spectral Density vs
Frequency
0.01
0.001
1k
Frequency (Hz)
C001
C008
Figure 16. THD+N vs Output Amplitude
2.0
1.8
1.7
1.8
1.6
1.5
IQ (mA)
IQ (mA)
Vs = ±18V
1.6
Vs = ±2.25V
1.4
1.3
1.4
1.2
1.1
1.2
1.0
±75
±50
±25
0
25
50
75
100
125
Temperature (ƒC)
Figure 17. Quiescent Current vs Temperature
150
0
4
8
12
16
20
24
28
32
Supply Voltage (V)
C001
36
C001
Figure 18. Quiescent Current vs Supply Voltage
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Typical Characteristics (continued)
at VS = ±18 V, VCM = VS / 2, RLOAD = 10 kΩ connected to VS / 2, and CL = 100 pF (unless otherwise noted)
180
140
25.0
CLOAD = 15 pF
20.0
120
15.0
135
Open-Loop Gain
Phase
60
90
40
Gain (dB)
10.0
80
Phase (ƒ)
Gain (dB)
100
5.0
0.0
±5.0
20
45
±10.0
0
G = +1
G = -10
G = -1
±15.0
±20
0
1
10
100
1k
10k
100k
1M
±20.0
1000
10M
Frequency (Hz)
100k
1M
10M
Frequency (Hz)
Figure 19. Open-Loop Gain and Phase vs Frequency
C003
Figure 20. Closed-Loop Gain vs Frequency
1000
2.0
1.5
100
1.0
ZO (Ω)
AOL (µV/V)
10k
C004
Vs = 4.5 V
10
0.5
Vs = 36 V
1
0.0
RL = 10kŸ
±0.5
±75
±50
±25
0
25
50
75
100
125
0.1
10
150
Temperature (ƒC)
RI = 1 k
-
+
VIN = 100 mV
1M
10M
100M
C016
Figure 22. Open-Loop Output Impedance vs Frequency
G = -1
40
CL
- 18 V
40
Overshoot (%)
Overshoot (%)
100k
ROUT
+
-
10k
50
RF = 1 k
+ 18 V
50
1k
Frequency (Hz)
Figure 21. Open-Loop Gain vs Temperature
60
100
C001
30
20
30
20
+ 18 V
ROUT = 0 Ω
10
ROUT= 0
10
-
R
RO
= 25
25
OUT =
R
25 Ω
RO
OUT==25
+
VIN = 100mV
ROUT
+
RL
CL
- 18 V
-
R
50 Ω
RO
OUT==50
0
0p
100p
200p
300p
400p
Capacitive Load (F)
500p
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0p
100p
200p
300p
Capacitive Load (F)
C013
Figure 23. Small-Signal Overshoot vs Capacitive Load
(100-mV Output Step)
10
RO
= 50
50
R
OUT =
0
400p
500p
C013
Figure 24. Small-Signal Overshoot vs Capacitive Load
(100-mV Output Step)
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Typical Characteristics (continued)
at VS = ±18 V, VCM = VS / 2, RLOAD = 10 kΩ connected to VS / 2, and CL = 100 pF (unless otherwise noted)
RI = 1 kΩ
RF = 10 kΩ
+ 18 V
-
+
VOUT
VIN = 2 V
+
-
VOUT
-18 V
5 V/div
5 V/div
RI = 1 kΩ
VOUT
RF = 10 kΩ
+ 18 V
-
+
VOUT
VIN = 2 V
+
-
- 18 V
VIN
VIN
Time (1 μs/div)
Time (1 μs/div)
C009
C009
Figure 25. Positive Overload Recovery
Figure 26. Positive Overload Recovery (Zoomed In)
VIN
RI = 1 kΩ
VIN
RF = 10 kΩ
5 V/div
5 V/div
+ 18 V
VOUT
RI = 1 kΩ
-
+
VOUT
VIN = 2 V
+
-
- 18 V
RF = 10 kΩ
+ 18 V
+
VIN = 2 V
-
VOUT
VOUT
+
-18 V
Time (1μs/div)
Time (1 μs/div)
C010
C010
Figure 27. Negative Overload Recovery
Figure 28. Negative Overload Recovery (Zoomed In)
RL = 1 kΩ
CL = 10 pF
+ 18 V
CL = 10 pF
+
VIN = 10 mV
CL
- 18 V
2 mV/div
2 mV/div
-
+
RI = 1 k
RF = 1 k
+ 18 V
+
VIN = 10 mV
-
+
RL
CL
- 18 V
Time (200 μ s/div)
Time (200 ns/div)
C006
Figure 29. Small-Signal Step Response (10 mV, G = –1)
C014
Figure 30. Small-Signal Step Response (10 mV, G = 1)
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Typical Characteristics (continued)
at VS = ±18 V, VCM = VS / 2, RLOAD = 10 kΩ connected to VS / 2, and CL = 100 pF (unless otherwise noted)
+ 18 V
CL = 10 pF
RL = 1 kΩ
CL = 10 pF
+
+
VIN = 100 mV
CL
- 18 V
20 mV/div
20 mV/div
-
RI = 1 kΩ
RF = 1 kΩ
+ 18 V
-
+
VIN= 100 mV
+
-
RL
CL
- 18 V
Time (200 ns/div)
Time (200 ns/div)
C014
C006
Figure 31. Small-Signal Step Response (100 mV, G = –1)
Figure 32. Small-Signal Step Response (100 mV, G = 1)
RL = 1 kΩ
CL = 10 pF
+ 18 V
CL = 10 pF
+
+
VIN = 10 V
2 V/div
2 V/div
CL
- 18 V
-
RI = 1 kΩ
RF = 1 kΩ
+ 18 V
-
+
VIN = 10 V
+
-
RL
CL
- 18 V
Time (500 ns/div)
Time (500 ns/div)
C014
Figure 33. Large-Signal Step Response (10 V, G = –1)
Figure 34. Large-Signal Step Response (10 V, G = 1)
20
20
G = +1
CL = 10 pF
15
Output Delta from Final Value (mV)
Output Delta from Final Value (mV)
C005
10
5
0
-5
0.1% Settling = ±10 mV
-10
-15
-20
10
5
0
-5
0.1% Settling = ±10 mV
-10
-15
-20
0
0.5
1
1.5
2
2.5
Time ( s)
3
3.5
4
4.5
5
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0
0.5
1
1.5
2
2.5
Time ( s)
C034
Figure 35. Large-Signal Settling Time (10-V Positive Step)
12
G = +1
CL = 10 pF
15
3
3.5
4
4.5
5
C034
Figure 36. Large-Signal Settling Time (10-V Negative Step)
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Typical Characteristics (continued)
at VS = ±18 V, VCM = VS / 2, RLOAD = 10 kΩ connected to VS / 2, and CL = 100 pF (unless otherwise noted)
100
+ 18 V
-
VOUT
VOUT
+
+
-
37 VPP - 18 V
Sine Wave
(±18.5 V)
75
ISC (mA)
5 V/div
ISC, Sink “18V
50
ISC, Source ±18V
25
VIN
0
±75
Time (200 μs/div)
±50
±25
0
50
75
100
125
150
C001
Figure 38. Short-Circuit Current vs Temperature
Figure 37. No Phase Reversal
160.0
30
VS = ±15 V
EMIRR IN+ (dB)
120.0
20
15
VS = ±5 V
10
100.0
80.0
60.0
40.0
VS = ±2.25 V
5
PRF = -10 dBm
VSUPPLY = ±18 V
VCM = 0 V
140.0
Maximum output voltage without
slew-rate induced distortion.
25
Output Voltage (VPP)
25
Temperature (ƒC)
C011
20.0
0
0.0
10k
100k
1M
10M
Frequency (Hz)
10M
100M
1G
Frequency (Hz)
C033
Figure 39. Maximum Output Voltage vs Frequency
10G
C017
Figure 40. EMIRR vs Frequency
Channel Separation (dB)
0
±20
±40
±60
±80
±100
±120
10
100
1k
10k
100k
1M
Frequency (Hz)
10M
C041
Figure 41. Channel Separation vs Frequency
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8 Detailed Description
8.1 Overview
The OPAx172-Q1 family of operational amplifiers provide high overall performance, making the devices ideal for
many general-purpose applications. The excellent offset drift of only 1.5 µV/°C (maximum) provides excellent
stability over the entire temperature range. In addition, the family offers very good overall performance with high
CMRR, PSRR, AOL, and superior THD.
The Functional Block Diagram section shows the simplified diagram of the OPA172-Q1 design. The design
topology is a highly-optimized, three-stage amplifier with an active-feedforward gain stage.
8.2 Functional Block Diagram
PCH
FF Stage
Ca
Cb
+IN
PCH
Input Stage
Output
Stage
2nd Stage
OUT
-IN
NCH
Input Stage
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8.3 Feature Description
8.3.1 EMI Rejection
The OPAx172-Q1 uses integrated electromagnetic interference (EMI) filtering to reduce the effects of EMI from
sources such as wireless communications and densely-populated boards with a mix of analog signal chain and
digital components. EMI immunity can be improved with circuit design techniques; the OPAx172-Q1 benefits
from these design improvements. Texas Instruments has developed the ability to accurately measure and
quantify the immunity of an operational amplifier over a broad frequency spectrum extending from 10 MHz to
6 GHz. Figure 42 shows the results of this testing on the OPAx172-Q1. Table 3 shows the EMIRR IN+ values for
the OPAx172-Q1 at particular frequencies commonly encountered in real-world applications. Applications listed in
Table 3 can be centered on or operated near the particular frequency shown. Detailed information can also be
found in the EMI Rejection Ratio of Operational Amplifiers application report (SBOA128), available for download
from www.ti.com.
160.0
PRF = -10 dBm
VSUPPLY = ±18 V
VCM = 0 V
140.0
EMIRR IN+ (dB)
120.0
100.0
80.0
60.0
40.0
20.0
0.0
10M
100M
1G
Frequency (Hz)
10G
C017
Figure 42. EMIRR Testing
Table 3. OPAx172-Q1 EMIRR IN+ for Frequencies of Interest
FREQUENCY
APPLICATION OR ALLOCATION
EMIRR IN+
400 MHz
Mobile radio, mobile satellite, space operation, weather, radar, ultrahigh frequency (UHF)
applications
47.6 dB
900 MHz
Global system for mobile communications (GSM) applications, radio communication, navigation,
GPS (to 1.6 GHz), GSM, aeronautical mobile, UHF applications
58.5 dB
1.8 GHz
GSM applications, mobile personal communications, broadband, satellite, L-band (1 GHz to 2 GHz)
2.4 GHz
802.11b, 802.11g, 802.11n, Bluetooth®, mobile personal communications, industrial, scientific and
medical (ISM) radio band, amateur radio and satellite, S-band (2 GHz to 4 GHz)
69.2 dB
3.6 GHz
Radiolocation, aero communication and navigation, satellite, mobile, S-band
82.9 dB
802.11a, 802.11n, aero communication and navigation, mobile communication, space and satellite
operation, C-band (4 GHz to 8 GHz)
114 dB
5 GHz
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8.3.2 Phase-Reversal Protection
The OPAx172-Q1 family has internal phase-reversal protection. Many op amps exhibit a phase reversal when
the input is driven beyond the linear common-mode range. This condition is most often encountered in
noninverting circuits when the input is driven beyond the specified common-mode voltage range, causing the
output to reverse into the opposite rail. The input of the OPAx172-Q1 prevents phase reversal with excessive
common-mode voltage. Instead, the appropriate rail limits the output voltage. This performance is shown in
Figure 43.
+ 18 V
-
VOUT
VOUT
+
-
37 VPP - 18 V
Sine Wave
(±18.5 V)
5 V/div
+
VIN
Time (200 μs/div)
C011
Figure 43. No Phase Reversal
8.3.3 Capacitive Load and Stability
The dynamic characteristics of the OPAx172-Q1 are optimized for commonly-used operating conditions. The
combination of low closed-loop gain and high capacitive loads decreases the phase margin of the amplifier and
can lead to gain peaking or oscillations. As a result, heavier capacitive loads must be isolated from the output.
The simplest way to achieve this isolation is to add a small resistor (for example, ROUT = 50 Ω) in series with the
output. Figure 44 and Figure 45 show graphs of small-signal overshoot versus capacitive load for several values
of ROUT. See the Feedback Plots Define Op Amp AC Performance application bulletin (SBOA015), available for
download from www.ti.com, for details of analysis techniques and application circuits.
60
RI = 1 k
50
RF = 1 k
G = -1
+ 18 V
50
-
+
VIN = 100 mV
40
CL
- 18 V
40
Overshoot (%)
Overshoot (%)
ROUT
+
-
30
20
30
20
+ 18 V
ROUT = 0 Ω
10
ROUT= 0
10
-
R
RO
= 25
25
OUT =
R
25 Ω
RO
OUT==25
+
VIN = 100mV
ROUT
+
RL
CL
- 18 V
-
R
50 Ω
RO
OUT==50
0
0p
100p
200p
300p
400p
Capacitive Load (F)
500p
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0p
100p
200p
300p
Capacitive Load (F)
C013
Figure 44. Small-Signal Overshoot vs Capacitive Load
(100-mV Output Step)
16
RO
= 50
50
R
OUT =
0
400p
500p
C013
Figure 45. Small-Signal Overshoot vs Capacitive Load
(100-mV Output Step)
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8.4 Device Functional Modes
8.4.1 Common-Mode Voltage Range
The input common-mode voltage range of the OPAx172-Q1 series extends 100 mV below the negative rail and
within 2 V of the top rail for normal operation.
This device can operate with a full rail-to-rail input 100 mV beyond the top rail, but with reduced performance
within 2 V of the top rail. The typical performance in this range is summarized in Table 4.
Table 4. Typical Performance Range (VS = ±18 V)
MIN
Input common-mode voltage
TYP
(V+) – 2
Offset voltage
MAX
(V+) + 0.1
UNIT
V
5
mV
Offset voltage vs temperature (TA = –40°C to +125°C)
10
µV/°C
Common-mode rejection
70
dB
Open-loop gain
60
dB
4
MHz
Gain bandwidth product (GBP)
Slew rate
Noise at f = 1 kHz
4
V/µs
22
nV/√Hz
8.4.2 Electrical Overstress
Designers often ask questions about the capability of an operational amplifier to withstand electrical overstress.
These questions tend to focus on the device inputs, but can involve the supply voltage terminals or even the
output terminal. Each of these different terminal functions have electrical stress limits determined by the voltage
breakdown characteristics of the particular semiconductor fabrication process and specific circuits connected to
the terminal. Additionally, internal electrostatic discharge (ESD) protection is built into these circuits for protection
from accidental ESD events both before and during product assembly.
A good understanding of this basic ESD circuitry and the relevance to an electrical overstress event is helpful.
Figure 46 illustrates the ESD circuits contained in the OPAx172-Q1 (indicated by the dashed line area). The ESD
protection circuitry involves several current-steering diodes connected from the input and output terminals and
routed back to the internal power-supply lines, where the diodes meet at an absorption device internal to the
operational amplifier. This protection circuitry is intended to remain inactive during normal circuit operation.
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TVS
+
±
RF
+VS
R1
IN±
250 Ÿ
RS
IN+
250 Ÿ
+
Power-Supply
ESD Cell
ID
VIN
RL
+
±
+
±
Copyright © 2016, Texas
Instruments Incorporated
±VS
TVS
Figure 46. Equivalent Internal ESD Circuitry Relative to a Typical Circuit Application
An ESD event produces a short-duration, high-voltage pulse that is transformed into a short-duration, highcurrent pulse when discharging through a semiconductor device. The ESD protection circuits are designed to
provide a current path around the operational amplifier core to prevent damage. The energy absorbed by the
protection circuitry is then dissipated as heat.
When an ESD voltage develops across two or more amplifier device terminals, current flows through one or more
steering diodes. Depending on the path that the current takes, the absorption device can activate. The absorption
device has a trigger, or threshold voltage, that is above the normal operating voltage of the OPAx172-Q1 but
below the device breakdown voltage level. When this threshold is exceeded, the absorption device quickly
activates and clamps the voltage across the supply rails to a safe level.
When the operational amplifier connects into a circuit (as shown in Figure 46), the ESD protection components
are intended to remain inactive and do not become involved in the application circuit operation. However,
circumstances can arise where an applied voltage exceeds the operating voltage range of a given terminal. If this
condition occurs, there is a risk that some internal ESD protection circuits can turn on and conduct current. Any
such current flow occurs through steering-diode paths and rarely involves the absorption device.
Figure 46 shows a specific example where the input voltage (VIN) exceeds the positive supply voltage (+VS) by
500 mV or more. Much of what happens in the circuit depends on the supply characteristics. If +VS can sink the
current, one of the upper input steering diodes conducts and directs current to +VS. Excessively high current
levels can flow with increasingly higher VIN. As a result, the data sheet specifications recommend that
applications limit the input current to 10 mA.
If the supply is not capable of sinking the current, VIN can begin sourcing current to the operational amplifier, and
then take over as the source of positive supply voltage. The danger in this case is that the voltage can rise to
levels that exceed the operational amplifier absolute maximum ratings.
18
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Another common question involves what happens to the amplifier if an input signal is applied to the input when
the power supplies +VS or –VS are at 0 V. Again, this question depends on the supply characteristic when at 0 V,
or at a level below the input-signal amplitude. If the supplies appear as high impedance, then the input source
supplies the operational amplifier current through the current-steering diodes. This state is not a normal bias
condition; most likely, the amplifier does not operate normally. If the supplies are low impedance, then the current
through the steering diodes can become quite high. The current level depends on the ability of the input source
to deliver current, and any resistance in the input path.
If there is any uncertainty about the ability of the supply to absorb this current, add external zener diodes to the
supply terminals; see Figure 46. Select the zener voltage so that the diode does not turn on during normal
operation. However, the zener voltage must be low enough so that the zener diode conducts if the supply
terminal begins to rise above the safe-operating, supply-voltage level.
The OPAx172-Q1 input terminals are protected from excessive differential voltage with back-to-back diodes; see
Figure 46. In most circuit applications, the input protection circuitry has no effect. However, in low-gain or G = 1
circuits, fast-ramping input signals can forward-bias these diodes because the output of the amplifier cannot
respond rapidly enough to the input ramp. If the input signal is fast enough to create this forward-bias condition,
limit the input signal current to 10 mA or less. If the input signal current is not inherently limited, an input series
resistor can be used to limit the input signal current. This input series resistor degrades the low-noise
performance of the OPAx172-Q1. Figure 46 illustrates an example configuration that implements a currentlimiting feedback resistor.
8.4.3 Overload Recovery
Overload recovery is defined as the time required for the op amp output to recover from the saturated state to
the linear state. The output devices of the op amp enter the saturation region when the output voltage exceeds
the rated operating voltage, either resulting from the high input voltage or the high gain. After the device enters
the saturation region, the charge carriers in the output devices need time to return back to the normal state. After
the charge carriers return back to the equilibrium state, the device begins to slew at the normal slew rate. Thus,
the propagation delay in case of an overload condition is the sum of the overload recovery time and the slew
time. The overload recovery time for the OPAx172-Q1 is approximately 200 ns.
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9 Applications 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.
9.1 Application Information
The OPAx172-Q1 family of amplifiers is specified for operation from 4.5 V to 36 V (±2.25 V to ±18 V). Many of
the specifications apply from –40°C to +125°C. Parameters that can exhibit significant variance with regard to
operating voltage or temperature are presented in the Typical Characteristics section.
9.2 Typical Applications
The following application examples highlight only a few of the circuits where the OPAx172-Q1 can be used.
9.2.1 Capacitive Load Drive Solution Using an Isolation Resistor
The OPA172-Q1 can be used capacitive loads such as cable shields, reference buffers, MOSFET gates, and
diodes. The circuit uses an isolation resistor (RISO) to stabilize the output of an op amp. RISO modifies the openloop gain of the system to ensure the circuit has sufficient phase margin, as shown in Figure 47.
+VS
VOUT
RISO
+
VIN
+
±
CLOAD
-VS
Figure 47. Unity-Gain Buffer with RISO Stability Compensation
9.2.1.1 Design Requirements
The design requirements are:
•
•
•
20
Supply voltage: 30 V (±15 V)
Capacitive loads: 100 pF, 1000 pF, 0.01 μF, 0.1 μF, and 1 μF
Phase margin: 45° and 60°
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Typical Applications (continued)
9.2.1.2 Detailed Design Procedure
Figure 47 depicts a unity-gain buffer driving a capacitive load. Equation 1 shows the transfer function for the
circuit in Figure 47. Not depicted in Figure 47 is the open-loop output resistance of the op amp, Ro.
1 + CLOAD × RISO × s
T(s) =
1 + Ro + RISO × CLOAD × s
(1)
The transfer function in Equation 1 has a pole and a zero. The frequency of the pole (fp) is determined by (Ro +
RISO) and CLOAD. Components RISO and CLOAD determine the frequency of the zero (fz). A stable system is
obtained by selecting RISO such that the rate of closure (ROC) between the open-loop gain (AOL) and 1 / β is
20 dB per decade. Figure 48 shows the concept. Note that the 1 / β curve for a unity-gain buffer is 0 dB.
120
AOL
100
1
fp
2 u Πu RISO
Gain (dB)
80
60
Ro
u CLOAD
40 dB
fz
40
1
2 u Πu RISO u CLOAD
1 dec
1/
20
ROC
20 dB
dec
0
10
100
1k
10k
100k
1M
10M
100M
Frequency (Hz)
Figure 48. Unity-Gain Amplifier with RISO Compensation
ROC stability analysis is typically simulated. The validity of the analysis depends on multiple factors, especially
the accurate modeling of Ro. In addition to simulating the ROC, a robust stability analysis includes a
measurement of overshoot percentage and ac gain peaking of the circuit using a function generator,
oscilloscope, and gain and phase analyzer. Phase margin is then calculated from these measurements. Table 5
shows the overshoot percentage and ac gain peaking that correspond to phase margins of 45° and 60°. For
more details on this design and other alternative devices that can be used in place of the OPA172-Q1, see the
Capacitive Load Drive Solution using an Isolation Resistorprecision design (TIPD128).
Table 5. Phase Margin versus Overshoot and AC Gain Peaking
PHASE MARGIN
OVERSHOOT
AC GAIN PEAKING
45°
23.3%
2.35 dB
60°
8.8%
0.28 dB
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9.2.1.3 Application Curve
The OPA172-Q1 meets the supply voltage requirements of 30 V. The OPA172-Q1 is tested for various capacitive
loads and RISO is adjusted to get an overshoot corresponding to Table 5. The results of the these tests are
summarized in Figure 49.
1000
60° Phase Margin
45° Phase Margin
RISO (Ÿ)
100
10
1
0.01
0.1
1
10
100
1000
CLOAD (nF)
C041
Figure 49. RISO vs CLOAD
9.2.2 Bidirectional Current Source
The improved Howland current-pump topology shown in Figure 50 provides excellent performance because of
the extremely tight tolerances of the on-chip resistors of the INA132. By buffering the output using an OPA172Q1, the output current the circuit is able to deliver is greatly extended.
The circuit dc transfer function is shown in Equation 2.
IOUT = VIN / R1
(2)
The OPA172-Q1 can also be used as the feedback amplifier because the low bias current minimizes error
voltages produced across R1. However, for improved performance, select a FET-input device with extremely low
offset, such as the OPA192, OPA140, or OPA188 as the feedback amplifier.
INA132
±IN
40 NŸ
40 NŸ
SENSE
VCC
OUTPUT
VIN
+
+
+IN
40 NŸ
40 NŸ
+
REF
VEE
Copyright © 2016, Texas
Instruments Incorporated
VCC
R1
+
VEE
IOUT
Figure 50. Bidirectional Current Source
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9.2.3 JFET-Input Low-Noise Amplifier
Figure 51 shows a low-noise composite amplifier built by adding a low noise JFET pair (Q1 and Q2) as an input
preamplifier for the OPA172-Q1. Transistors Q3 and Q4 form a 2-mA current sink that biases each JFET with 1
mA of drain current. Using 3.9-kΩ drain resistors produces a gain of approximately 10 in the input amplifier,
making the extremely-low, broadband-noise spectral density of the JFET pair, Q1 and Q2, the dominant noise
source of the amplifier. The output impedance of the input differential amplifier is large enough that a FET-input
amplifier such as the OPA172-Q1 provides superior noise performance over bipolar-input amplifiers.
The gain of the composite amplifier is given by Equation 3.
AV = (1 + R3 / R4)
(3)
The resistances shown are standard 1% resistor values that produce a gain of approximately 100 (99.26) with
68° of phase margin. Gains less than 10 may require additional compensation methods to provide stability.
Select low resistor values to minimize the resistor thermal noise contribution to the total output noise.
VCC
VCC
V1
15 V
VEE
V2
15 V
R1
3.9 kŸ
R2
3.9 kŸ
VEE
VOUT
++
LSK489
Q1
R3
1.13 kŸ
VCC
Q2
VCC
R6
27.4 kŸ
Q3
R4
11.5 Ÿ
MMBT4401
Q4
MMBT4401
R5
300 Ÿ
Copyright © 2016, Texas
Instruments Incorporated
VEE
Figure 51. JFET-Input Low-Noise Amplifier
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10 Power Supply Recommendations
The OPA172-Q1 is specified for operation from 4.5 V to 36 V (±2.25 V to ±18 V); many specifications apply from
–40°C to +125°C. Parameters that can exhibit significant variance with regard to operating voltage or
temperature are presented in the Typical Characteristics section.
CAUTION
Supply voltages larger than 40 V can permanently damage the device; see the
Absolute Maximum Ratings table.
Place 0.1-μF bypass capacitors close to the power-supply terminals to reduce errors coupling in from noisy or
high-impedance power supplies. For more detailed information on bypass capacitor placement, see the Layout
section.
11 Layout
11.1 Layout Guidelines
For best operational performance of the device, use good printed circuit board (PCB) layout practices, including:
• Noise can propagate into analog circuitry through the power pins of the circuit as a whole and of op amp
itself. Bypass capacitors are used to reduce the coupled noise by providing low-impedance power
sources local to the analog circuitry.
– Connect low-ESR, 0.1-µF ceramic bypass capacitors between each supply pin and ground, placed as
close to the device as possible. A single bypass capacitor from V+ to ground is applicable for singlesupply applications.
• Separate grounding for analog and digital portions of circuitry is one of the simplest and most-effective
methods of noise suppression. One or more layers on multilayer PCBs are usually devoted to ground
planes. A ground plane helps distribute heat and reduces EMI noise pickup. Make sure to physically
separate digital and analog grounds paying attention to the flow of the ground current.
• In order to reduce parasitic coupling, run the input traces as far away from the supply or output traces as
possible. If these traces cannot be kept separate, crossing the sensitive trace perpendicular as opposed
to in parallel with the noisy trace is preferable.
• Place the external components as close to the device as possible. As illustrated in Figure 52, keeping RF
and RG close to the inverting input minimizes parasitic capacitance.
• Keep the length of input traces as short as possible. Always remember that the input traces are the most
sensitive part of the circuit.
• Consider a driven, low-impedance guard ring around the critical traces. A guard ring can significantly
reduce leakage currents from nearby traces that are at different potentials.
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11.2 Layout Example
Place components close
to device and to each
other to reduce parasitic
errors
Run the input traces
as far away from
the supply lines
as possible
V+
RF
N/C
N/C
±IN
V+
+IN
OUTPUT
V±
N/C
RG
GND
VIN
GND
VS±
VOUT
GND
Use a low-ESR, ceramic
bypass capacitor
Ground (GND) plane on another layer
Use low-ESR,
ceramic bypass
capacitor
Copyright © 2017, Texas Instruments Incorporated
Figure 52. Operational Amplifier Board Layout for a Noninverting Configuration
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12 Device and Documentation Support
12.1 Device Support
12.1.1 Development Support
12.1.1.1 TINA-TI™ (Free Software Download)
TINA-TI™ is a simple, powerful, and easy-to-use circuit simulation program based on a SPICE engine. TINATI™ is a free, fully-functional version of the TINA-TI™ software, preloaded with a library of macro models in
addition to a range of both passive and active models. TINA-TI™ provides all the conventional dc, transient, and
frequency domain analysis of SPICE, as well as additional design capabilities.
Available as a free download from the Analog eLab Design Center, TINA-TI™ offers extensive post-processing
capability that allows users to format results in a variety of ways. Virtual instruments offer the ability to select
input waveforms and probe circuit nodes, voltages, and waveforms, creating a dynamic quick-start tool.
NOTE
These files require that either the TINA software (from DesignSoft™) or TINA-TI™
software be installed. Download the free TINA-TI™ software from the TINA-TI™ folder.
12.2 Documentation Support
12.2.1 Related Documentation
For related documentation see the following:
• Feedback Plots Define Op Amp AC Performance (SBOA015)
• EMI Rejection Ratio of Operational Amplifiers (SBOA128)
• Capacitive Load Drive Solution using an Isolation Resistor (TIDU032)
• INA132 Low Power, Single-Supply Difference Amplifier (SBOS059)
• OPAx192 36-V, Precision, Rail-to-Rail Input/Output, Low Offset Voltage, Low Input Bias Current Op Amp with
e-trim™ (SBOS620)
• OPA140 High-Precision, Low-Noise, Rail-to-Rail Output, 11-MHz JFET Op Amp (SBOS498)
• OPA188 Precision, Low-Noise, Rail-to-Rail Output, 36-V, Zero-Drift Operational Amplifier (SBOS642)
12.3 Related Links
The table below lists quick access links. Categories include technical documents, support and community
resources, tools and software, and quick access to order now.
Table 6. Related Links
PARTS
PRODUCT FOLDER
ORDER NOW
TECHNICAL
DOCUMENTS
TOOLS &
SOFTWARE
SUPPORT &
COMMUNITY
OPA2172-Q1
Click here
Click here
Click here
Click here
Click here
OPA4172-Q1
Click here
Click here
Click here
Click here
Click here
12.4 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.
26
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SBOS809A – NOVEMBER 2016 – REVISED JUNE 2017
12.5 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.
12.6 Trademarks
TINA-TI, E2E are trademarks of Texas Instruments.
Bluetooth is a registered trademark of Bluetooth SIG, Inc.
DesignSoft is a trademark of DesignSoft, Inc.
All other trademarks are the property of their respective owners.
12.7 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.
12.8 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
13 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.
Copyright © 2016–2017, Texas Instruments Incorporated
Product Folder Links: OPA2172-Q1 OPA4172-Q1
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PACKAGE OPTION ADDENDUM
www.ti.com
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)
OPA2172QDGKQ1
ACTIVE
VSSOP
DGK
8
80
RoHS & Green
NIPDAUAG
Level-2-260C-1 YEAR
-40 to 125
18W6
OPA2172QDGKRQ1
ACTIVE
VSSOP
DGK
8
2500
RoHS & Green
NIPDAUAG
Level-2-260C-1 YEAR
-40 to 125
18W6
OPA4172AQPWRQ1
ACTIVE
TSSOP
PW
14
2000
RoHS & Green
NIPDAU
Level-2-260C-1 YEAR
-40 to 125
4172Q1
(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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