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LMV841, LMV842, LMV844
SNOSAT1I – OCTOBER 2006 – REVISED OCTOBER 2017
LMV84x CMOS Input, RRIO, Low Power, Wide Supply Range,
4.5-MHz Operational Amplifiers
1 Features
3 Description
•
The LMV84x devices are low-voltage and low-power
operational amplifiers that operate with supply
voltages ranging from 2.7 V to 12 V and have rail-torail input and output capability. Their low offset
voltage, low supply current, and CMOS inputs make
them ideal for high impedance sensor interface and
battery-powered applications.
1
•
•
•
•
•
•
•
•
•
•
•
•
Unless Otherwise Noted, Typical Values at
TA = 25 °C, V+ = 5 V.
Small 5-Pin SC70 Package (2.00 mm × 1.25 mm
× 0.95 mm)
Wide Supply Voltage Range: 2.7 V to 12 V
Specified Performance at 3.3 V, 5 V and ±5 V
Low Supply Current: 1 mA Per Channel
Unity Gain Bandwidth: 4.5 MHz
Open-Loop Gain: 133 dB
Input Offset Voltage: 500 µV Maximum
Input Bias Current: 0.3 pA
CMRR at 112 dB and PSSR at 108 dB
Input Voltage Noise: 20 nV/√Hz
Temperature Range: −40°C to 125°C
Rail-to-Rail Input and Output (RRIO)
The single LMV841 is offered in the space-saving 5pin SC70 package, the dual LMV842 in the 8-pin
VSSOP and 8-pin SOIC packages, and the quad
LMV844 in the 14-pin TSSOP and 14-pin SOIC
packages. These small packages are ideal solutions
for area-constrained PCBs and portable electronics.
Device Information(1)
PART NUMBER
LMV841
LMV842
2 Applications
•
•
•
•
LMV844
High Impedance Sensor Interface
Battery-Powered Instrumentation
High Gain and Instrumentation Amplifiers
DAC Buffers and Active Filters
PACKAGE
BODY SIZE (NOM)
SC70 (5)
2.00 mm × 1.25 mm
VSSOP (8)
3.00 mm × 3.00 mm
SOIC (8)
4.90 mm × 3.91 mm
SOIC (14)
8.65 mm × 3.91 mm
TSSOP (14)
5.00 mm × 4.40 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Typical Applications
-
VIN
+
+
Active Band-Pass Filter
SENSOR
RS
+
VS
+
-
RS
-
+
LOAD
High Impedance Sensor Interface
CMOS Input Feature
High-Side, Current-Sensing
Rail-to-Rail Input and Output Feature
Copyright © 2016, Texas Instruments Incorporated
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,
intellectual property matters and other important disclaimers. PRODUCTION DATA.
LMV841, LMV842, LMV844
SNOSAT1I – OCTOBER 2006 – REVISED OCTOBER 2017
www.ti.com
Table of Contents
1
2
3
4
5
6
Features ..................................................................
Applications ...........................................................
Description .............................................................
Revision History.....................................................
Pin Configuration and Functions .........................
Specifications.........................................................
6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
7
1
1
1
2
3
4
Absolute Maximum Ratings ...................................... 4
ESD Ratings.............................................................. 4
Recommended Operating Conditions....................... 4
Thermal Information .................................................. 4
Electrical Characteristics – 3.3 V ............................. 5
Electrical Characteristics – 5 V ................................ 6
Electrical Characteristics – ±5-V .............................. 7
Typical Characteristics ............................................ 10
Detailed Description ............................................ 16
7.1 Overview ................................................................. 16
7.2 Functional Block Diagram ....................................... 16
7.3 Feature Description................................................. 16
7.4 Device Functional Modes........................................ 17
7.5 Interfacing to High Impedance Sensor .................. 20
8
Application and Implementation ........................ 21
8.1 Application Information............................................ 21
8.2 Typical Applications ................................................ 21
9 Power Supply Recommendations...................... 25
10 Layout................................................................... 25
10.1 Layout Guidelines ................................................. 25
10.2 Layout Example .................................................... 25
11 Device and Documentation Support ................. 26
11.1
11.2
11.3
11.4
11.5
11.6
Related Links ........................................................
Receiving Notification of Documentation Updates
Community Resources..........................................
Trademarks ...........................................................
Electrostatic Discharge Caution ............................
Glossary ................................................................
26
26
26
26
26
26
12 Mechanical, Packaging, and Orderable
Information ........................................................... 26
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision H (July 2016) to Revision I
Page
•
Changed ESD Ratings table footnotes to TI standard .......................................................................................................... 4
•
Changed Thermal Information table ....................................................................................................................................... 4
•
Changed Phase Margin vs CL graphic ................................................................................................................................ 13
•
Changed Overshoot vs CL graphic ....................................................................................................................................... 14
Changes from Revision G (February 2013) to Revision H
•
Page
Added ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation
section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and
Mechanical, Packaging, and Orderable Information section. ................................................................................................. 1
Changes from Revision F (February 2013) to Revision G
•
2
Page
Changed layout of National Semiconductor Data Sheet to TI format .................................................................................. 23
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Copyright © 2006–2017, Texas Instruments Incorporated
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SNOSAT1I – OCTOBER 2006 – REVISED OCTOBER 2017
5 Pin Configuration and Functions
DCK Package
5-Pin SC70
Top View
D or DGK Package
8-Pin SOIC and VSSOP
Top View
D or PW Package
14-Pin SOIC and TSSOP
Top View
Pin Functions
PIN
NAME
DESCRIPTION
I/O.
+IN
I
Noninverting Input
–IN
I
Inverting Input
OUT
O
Output
V+
P
Positive Supply
V–
P
Negative Supply
Copyright © 2006–2017, Texas Instruments Incorporated
Product Folder Links: LMV841 LMV842 LMV844
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SNOSAT1I – OCTOBER 2006 – REVISED OCTOBER 2017
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6 Specifications
6.1 Absolute Maximum Ratings
(1) (2)
See
MIN
MAX
UNIT
–300
300
mV
13.2
V
V+ + 0.3
V− – 0.3
V
10
mA
VIN differential
+
−
Supply voltage (V – V )
Voltage at input and output pins
Input current
Junction temperature
Soldering
information
(3)
150
°C
Infrared or convection (20 s)
235
°C
Wave soldering lead temperature (10 s)
260
°C
150
°C
−65
Storage temperature, Tstg
(1)
(2)
(3)
Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings
only and functional operation of the device at these conditions is not implied. Exposure to absolute-maximum-rated conditions for
extended periods may affect device reliability.
If Military/Aerospace specified devices are required, contact the Texas Instruments Sales Office / Distributors for availability and
specifications.
The maximum power dissipation is a function of TJ(MAX), RθJA, and TA. The maximum allowable power dissipation at any ambient
temperature is PD = (TJ(MAX) - TA) / RθJA. All numbers apply for packages soldered directly onto a PCB.
6.2 ESD Ratings
VALUE
Electrostatic
discharge
V(ESD)
(1)
(2)
Human-body model (HBM)
(1)
UNIT
±2000
Charged-device model (CDM), per JEDEC specification JESD22-C101 (2)
V
±250
JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
6.3 Recommended Operating Conditions
Temperature
(1)
Supply voltage (V+ – V−)
(1)
MIN
MAX
UNIT
−40
125
°C
2.7
12
V
The maximum power dissipation is a function of TJ(MAX), RθJA, and TA. The maximum allowable power dissipation at any ambient
temperature is PD = (TJ(MAX) – TA) / RθJA. All numbers apply for packages soldered directly onto a PCB.
6.4 Thermal Information
LMV84x
THERMAL METRIC (1)
DCK (SC70)
DGK
(VSSOP)
D (SOIC)
PW
(TSSOP)
UNIT
5 PINS
8 PINS
8 PINS
14 PIN
14 PINS
RθJA
Junction-to-ambient thermal resistance (2)
269.9
179.2
121.4
85.4
113.3
°C/W
RθJC(top)
Junction-to-case (top) thermal resistance
93.8
69.2
65.7
43.5
38.9
°C/W
RθJB
Junction-to-board thermal resistance
48.8
99.7
62.0
39.8
56.3
°C/W
ψJT
Junction-to-top characterization parameter
2.0
10.0
16.5
9.2
3.1
°C/W
ψJB
Junction-to-board characterization parameter
47.9
98.3
61.4
39.6
55.6
°C/W
RθJC(bot)
Junction-to-case (bottom) thermal resistance
N/A
N/A
N/A
N/A
N/A
°C/W
(1)
(2)
4
For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report.
The maximum power dissipation is a function of TJ(MAX), RθJA, and TA. The maximum allowable power dissipation at any ambient
temperature is PD = (TJ(MAX) - TA) / RθJA. All numbers apply for packages soldered directly onto a PCB.
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SNOSAT1I – OCTOBER 2006 – REVISED OCTOBER 2017
6.5 Electrical Characteristics – 3.3 V
Unless otherwise specified, all limits are ensured for TA = 25°C, V+ = 3.3 V, V− = 0 V, VCM = V+ / 2, and RL > 10 MΩ to V+ /
2. (1)
PARAMETER
VOS
TEST CONDITIONS
Input offset voltage
TCVOS
Input offset voltage drift
Input bias current
IB
MIN (2)
TYP (3)
MAX (2)
–500
±50
500
at the temperature extremes
–800
at the temperature extremes
–5
(4)
800
0.5
(4) (5)
5
0.3
at the temperature extremes
IOS
300
Input offset current
Common-mode rejection ratio
LMV841
CMRR
Common-mode rejection ratio
LMV842 and LMV844
PSRR
Power supply rejection ratio
CMVR
Input common-mode voltage
range
40
84
0 V ≤ VCM ≤ 3.3 V
at the temperature
extremes
2.7 V ≤ V+ ≤ 12 V, VO = V+
/2
at the temperature
extremes
CMRR ≥ 50 dB, at the temperature extremes
Large signal voltage gain
RL = 10 kΩ
VO = 0.2 V to 3.1 V
at the temperature
extremes
at the temperature
extremes
106
dB
108
dB
–0.1
3.4
dB
131
dB
96
52
RL = 2 kΩ to V+/2
at the temperature
extremes
RL = 10 kΩ to V+/2
at the temperature
extremes
RL = 2 kΩ to V+/2
at the temperature
extremes
RL = 10 kΩ to V+/2
at the temperature
extremes
Output swing high,
(measured from V+)
(1)
(2)
(3)
(4)
(5)
mV
100
120
33
mV
50
70
65
Output swing low,
(measured from V−)
80
120
28
VO
V
123
96
100
pA
dB
82
100
µV/°C
fA
75
86
at the temperature
extremes
µV
112
80
77
0 V ≤ VCM ≤ 3.3 V
RL = 2 kΩ
VO = 0.3 V to 3 V
AVOL
10
UNIT
mV
65
75
mV
Electrical table values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very
limited self-heating of the device.
Limits are 100% production tested at 25°C. Limits over the operating temperature range are ensured through correlations using
statistical quality control (SQC) method.
Typical values represent the most likely parametric norm as determined at the time of characterization. Actual typical values may vary
over time and will also depend on the application and configuration. The typical values are not tested and are not ensured on shipped
production material.
This parameter is ensured by design and/or characterization and is not tested in production.
Positive current corresponds to current flowing into the device.
Copyright © 2006–2017, Texas Instruments Incorporated
Product Folder Links: LMV841 LMV842 LMV844
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Electrical Characteristics – 3.3 V (continued)
Unless otherwise specified, all limits are ensured for TA = 25°C, V+ = 3.3 V, V− = 0 V, VCM = V+ / 2, and RL > 10 MΩ to V+ /
2.(1)
PARAMETER
TEST CONDITIONS
Sourcing VO = V+/2
VIN = 100 mV
at the temperature
extremes
Output short-circuit current (6) (7)
IO
MIN (2)
TYP (3)
20
32
at the temperature
extremes
mA
27
mA
15
0.93
IS
Supply current
SR
Slew rate
GBW
Gain bandwidth product
Φm
Phase margin
en
Input-referred voltage noise
f = 1 kHz
20
ROUT
Open-loop output impedance
f = 3 MHz
70
(8)
THD+N Total harmonic distortion + noise
CIN
(6)
(7)
(8)
Per channel
UNIT
15
20
Sinking VO = V+/2
VIN = −100 mV
MAX (2)
1.5
at the temperature
extremes
mA
2
AV = 1, VO = 2.3 VPP
10% to 90%
2.5
V/µs
4.5
MHz
67
f = 1 kHz , AV = 1
RL = 10 kΩ
Deg
nV/
Ω
0.005%
Input capacitance
7
pF
The maximum power dissipation is a function of TJ(MAX), RθJA, and TA. The maximum allowable power dissipation at any ambient
temperature is PD = (TJ(MAX) – TA) / RθJA. All numbers apply for packages soldered directly onto a PCB.
Short circuit test is a momentary test.
Number specified is the slower of positive and negative slew rates.
6.6 Electrical Characteristics – 5 V
Unless otherwise specified, all limits are ensured for TA = 25°C, V+ = 5 V, V− = 0 V, VCM = V+ / 2, and RL > 10 MΩ to V+ / 2. (1)
PARAMETER
VOS
Input offset voltage
TCVOS
Input offset voltage drift (4)
IB
Input bias current (4) (5)
IOS
Input offset current
TEST CONDITIONS
(1)
(2)
(3)
(4)
(5)
6
TYP (3)
MAX (2)
–500
±50
500
at the temperature extremes
–800
at the temperature extremes
–5
800
0.35
5
0.3
at the temperature extremes
40
Common-mode rejection ratio
LMV841
0 V ≤ VCM ≤ 5 V
at the temperature
extremes
Common-mode rejection ratio
LMV842 and LMV844
0 V ≤ VCM ≤ 5 V
at the temperature
extremes
Power supply rejection ratio
2.7 V ≤ V+ ≤ 12 V, VO =
at the temperature
V+/2
extremes
10
300
86
CMRR
PSRR
MIN (2)
82
µV/°C
pA
fA
dB
106
dB
79
86
µV
112
80
81
UNIT
108
dB
Electrical table values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very
limited self-heating of the device.
Limits are 100% production tested at 25°C. Limits over the operating temperature range are ensured through correlations using
statistical quality control (SQC) method.
Typical values represent the most likely parametric norm as determined at the time of characterization. Actual typical values may vary
over time and will also depend on the application and configuration. The typical values are not tested and are not ensured on shipped
production material.
This parameter is ensured by design and/or characterization and is not tested in production.
Positive current corresponds to current flowing into the device.
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Electrical Characteristics – 5 V (continued)
Unless otherwise specified, all limits are ensured for TA = 25°C, V+ = 5 V, V− = 0 V, VCM = V+ / 2, and RL > 10 MΩ to V+ / 2.(1)
PARAMETER
CMVR
TEST CONDITIONS
CMRR ≥ 50 dB, at the temperature extremes
Input common-mode voltage
range
RL = 2 kΩ
VO = 0.3V to 4.7 V
AVOL
Large signal voltage gain
RL = 10 kΩ
VO = 0.2V to 4.8V
MIN (2)
–0.2
100
at the temperature
extremes
at the temperature
extremes
RL = 10 kΩ to V+/2
at the temperature
extremes
RL = 2 kΩ to V+/2
at the temperature
extremes
Output swing high,
(measured from V+)
dB
133
dB
96
Sourcing VO = V+/2
VIN = 100 mV
Output short-circuit current (6)
IO
(7)
Sinking VO = V+/2
VIN = −100 mV
20
mA
15
Slew rate
GBW
Gain bandwidth product
Φm
Phase margin
en
Input-referred voltage noise
f = 1 kHz
20
ROUT
Open-loop output impedance
f = 3 MHz
70
THD+N
Total harmonic distortion +
noise
f = 1 kHz , AV = 1
RL = 10 kΩ
CIN
Input capacitance
(7)
(8)
mV
28
SR
(6)
70
mA
Supply current
at the temperature
extremes
AV = 1, VO = 4 VPP
10% to 90%
mV
15
IS
(8)
120
33
0.96
Per channel
mV
80
20
at the temperature
extremes
50
140
at the temperature
extremes
at the temperature
extremes
mV
70
38
RL = 10 kΩ to V+/2
100
120
78
Output swing low,
(measured from V–)
V
125
32
VO
UNIT
5.2
68
RL = 2 kΩ to V+/2
MAX (2)
96
100
at the temperature
extremes
TYP (3)
1.5
mA
2
2.5
V/µs
4.5
MHz
67
Deg
nV/
Ω
0.003%
6
pF
The maximum power dissipation is a function of TJ(MAX), RθJA, and TA. The maximum allowable power dissipation at any ambient
temperature is PD = (TJ(MAX) - TA) / RθJA. All numbers apply for packages soldered directly onto a PCB.
Short circuit test is a momentary test.
Number specified is the slower of positive and negative slew rates.
6.7 Electrical Characteristics – ±5-V
Unless otherwise specified, all limits are ensured for TA = 25°C, V+ = 5 V, V− = –5 V, VCM = 0 V, and RL > 10 MΩ to VCM. (1)
(1)
Electrical table values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very
limited self-heating of the device.
Copyright © 2006–2017, Texas Instruments Incorporated
Product Folder Links: LMV841 LMV842 LMV844
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Electrical Characteristics – ±5-V (continued)
Unless otherwise specified, all limits are ensured for TA = 25°C, V+ = 5 V, V− = –5 V, VCM = 0 V, and RL > 10 MΩ to VCM.(1)
PARAMETER
VOS
Input offset voltage
TCVOS
Input offset voltage drift
TEST CONDITIONS
at the temperature extremes
Input bias current
TYP (3)
MAX (2)
–500
±50
500
–800
(4)
800
0.25
at the temperature extremes
IB
MIN (2)
–5
(4) (5)
5
0.3
at the temperature extremes
IOS
Input offset current
40
86
Common-mode rejection ratio
LMV841
–5 V ≤ VCM ≤ 5 V
at the temperature
extremes
Common-mode rejection ratio
LMV842 and LMV844
–5 V ≤ VCM ≤ 5 V
at the temperature
extremes
PSRR
Power supply rejection ratio
2.7 V ≤ V+ ≤ 12 V, VO =
at the temperature
0V
extremes
CMVR
Input common-mode voltage
range
CMRR ≥ 50 dB
CMRR
Large signal voltage gain
RL = 10 kΩ
VO = −4.8 V to 4.8 V
106
dB
108
dB
–5.2
100
5.2
100
dB
136
dB
96
95
RL = 2 kΩ to 0 V
Output swing high,
(measured from V+)
VO
RL = 10 kΩ to 0 V
at the temperature
extremes
Sourcing VO = 0 V
VIN = 100 mV
Output short-circuit current
(6) (7)
Sinking VO = 0 V
VIN = −100 mV
(2)
(3)
(4)
(5)
(6)
(7)
8
20
20
15
mV
37
mA
15
at the temperature
extremes
mV
80
100
at the temperature
extremes
mV
160
200
52
mV
75
95
105
at the temperature
extremes
130
155
at the temperature
extremes
RL = 2 kΩ to 0 V
Output swing low,
(measured from V−)
IO
at the temperature
extremes
44
RL = 10 kΩ to 0 V
V
126
96
at the temperature
extremes
pA
dB
82
at the temperature
extremes
µV/°C
112
80
86
µV
fA
80
86
RL = 2 kΩ
VO = −4.7 V to 4.7 V
AVOL
10
300
UNIT
29
mA
Limits are 100% production tested at 25°C. Limits over the operating temperature range are ensured through correlations using
statistical quality control (SQC) method.
Typical values represent the most likely parametric norm as determined at the time of characterization. Actual typical values may vary
over time and will also depend on the application and configuration. The typical values are not tested and are not ensured on shipped
production material.
This parameter is ensured by design and/or characterization and is not tested in production.
Positive current corresponds to current flowing into the device.
The maximum power dissipation is a function of TJ(MAX), RθJA, and TA. The maximum allowable power dissipation at any ambient
temperature is PD = (TJ(MAX) - TA) / RθJA. All numbers apply for packages soldered directly onto a PCB.
Short circuit test is a momentary test.
Submit Documentation Feedback
Copyright © 2006–2017, Texas Instruments Incorporated
Product Folder Links: LMV841 LMV842 LMV844
LMV841, LMV842, LMV844
www.ti.com
SNOSAT1I – OCTOBER 2006 – REVISED OCTOBER 2017
Electrical Characteristics – ±5-V (continued)
Unless otherwise specified, all limits are ensured for TA = 25°C, V+ = 5 V, V− = –5 V, VCM = 0 V, and RL > 10 MΩ to VCM.(1)
PARAMETER
TEST CONDITIONS
TYP (3)
MAX (2)
1.03
1.7
IS
Supply current
SR
Slew rate
GBW
Φm
en
Input-referred voltage noise
f = 1 kHz
20
ROUT
Open-loop output impedance
f = 3 MHz
70
THD+N
Total harmonic distortion + noise
f = 1 kHz , AV = 1
RL = 10kΩ
CIN
Input capacitance
(8)
(8)
Per channel
MIN (2)
at the temperature
extremes
AV = 1, VO = 9 VPP
10% to 90%
2
UNIT
mA
2.5
V/µs
Gain bandwidth product
4.5
MHz
Phase margin
67
Deg
nV/
Ω
0.006%
3
pF
Number specified is the slower of positive and negative slew rates.
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Product Folder Links: LMV841 LMV842 LMV844
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6.8 Typical Characteristics
At TA = 25°C, RL = 10 kΩ, VS = 5 V. Unless otherwise specified.
200
200
VS = 3.3V
150
125°C
100
85°C
50
VOS (PV)
VOS (PV)
100
VS = 5.0V
150
0
-50
-100
50
125°C
0
85°C
-50
25°C
-100
25°C
-150
-150
-40°C
-200
-1
0
1
2
3
-200
-1
4
-40°C
0
1
2
VCM (V)
3
4
5
6
VCM (V)
Figure 1. VOS vs VCM Over Temperature at 3.3 V
Figure 2. VOS vs VCM Over Temperature at 5 V
200
200
VS = ±5V
150
150
125°C
100
0
VOS (PV)
85°C
50
VOS (PV)
100
25°C
125°C
50
0
85°C
-50
-50
25°C
-100
-40°C
-100
-150
-150
-200
-6
-200
2
-40°C
-4
-2
0
2
4
6
4
6
8
10
12
14
VCM (V)
VSUPPLY (V)
Figure 3. VOS vs VCM Over Temperature at ±5 V
Figure 4. VOS vs Supply Voltage
140
200
RL = 10 k:
OPEN LOOP GAIN (dB)
150
VOS (PV)
100
50
0
3.3V
-50
±5V
-100
5V
130
RL = 2 k:
120
110
RL = 600Ö
100
-150
-200
-50
-25
0
25
50
75
100
125
TEMPERATURE (°C)
Figure 5. VOS vs Temperature
10
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90
0
100
200
300
400
500
OUTPUT SWING FROM RAIL (mV)
Figure 6. DC Gain vs VOUT
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Typical Characteristics (continued)
At TA = 25°C, RL = 10 kΩ, VS = 5 V. Unless otherwise specified.
20
TA = 25°C
0.15
15
0.10
10
0.05
5
IBIAS (pA)
IBIAS (pA)
0.20
0
-0.05
TA = 85°C
0
5.0V
-5
5V
-0.10
-10
±5V
-0.15
-0.20
-5
-4
-3
-2
-1
0
1
±5V
-15
3.3V
2
3
4
-20
-5
5
3.3V
-4
-3
-2
-1
VCM (V)
1
2
3
4
5
VCM (V)
Figure 7. Input Bias Current vs VCM
Figure 8. Input Bias Current vs VCM
200
1.4
TA = 125°C
125°C
150
SUPPLY CURRENT (mA)
1.3
100
IBIAS (pA)
0
50
0
5.0V
-50
-100
±5V
85°C
1.1
25°C
1.0
0.9
3.3V
-150
1.2
-40°C
-200
-5
-4
-3
-2
-1
0
1
2
3
4
0.8
2
5
4
6
VCM (V)
8
10
12
14
SUPPLY VOLTAGE (V)
Figure 9. Input Bias Current vs VCM
Figure 10. Supply Current Per Channel vs Supply Voltage
40
45
125°C
85°C
-40°C
40
25°C
ISOURCE (mA)
ISINK (mA)
35
30
25
20
2
4
6
85°C
125°C
8
10
35
25°C
-40°C
30
12
25
2
4
SUPPLY VOLTAGE (V)
Figure 11. Sinking Current vs Supply Voltage
6
8
10
12
SUPPLY VOLTAGE (V)
Figure 12. Sourcing Current vs Supply Voltage
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Typical Characteristics (continued)
At TA = 25°C, RL = 10 kΩ, VS = 5 V. Unless otherwise specified.
135
65
RL = 2 k:
60
125°C
VOUT FROM RAIL HIGH (mV)
115
85°C
105
95
85
75
25°C
65
55
-40°C
RL = 10 k:
55
125°C
50
85°C
45
40
35
25°C
30
-40°C
25
20
45
35
2
4
6
8
10
12
15
2
14
4
Figure 13. Output Swing High vs Supply Voltage RL = 2 kΩ
VOUT FROM RAIL LOW (mV)
VOUT FROM RAIL LOW (mV)
70
125°C
130
85°C
120
110
100
90
25°C
80
70
-40°C
60
4
6
RL = 10 k:
125°C
65
60
85°C
55
50
45
25°C
40
-40°C
35
8
10
12
25
2
14
4
SINK
125°C
0.4
6
8
10
12
14
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
Figure 16. Output Swing Low vs Supply Voltage RL = 10 kΩ
60
85°C
130
GAIN
PHASE
-40°C
0.3
0.2
90
40
-40°C
25°C
0.1
VS = 3.3V, 5.0V, +/-5V
0
-0.1
25°C
GAIN (dB)
VOUT FROM RAIL (V)
14
30
Figure 15. Output Swing Low vs Supply Voltage RL = 2 kΩ
125°C
-40°C
20
10
0
125°C 85°C
-0.4
125°C
CL = 20 pF
-20
10k
100k
SOURCE
-0.5
0
5
10
15
20
ILOAD (mA)
25
30
Figure 17. Output Voltage Swing vs Load Current
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-40°C
-0.2
-0.3
12
12
75
140
0.5
10
Figure 14. Output Swing High vs Supply Voltage RL = 10 kΩ
RL = 2 k:
50
2
8
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
150
6
PHASE (°)
VOUT FROM RAIL HIGH (mV)
125
1M
-30
10M
FREQUENCY (Hz)
Figure 18. Open-Loop Frequency Response Over
Temperature
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Typical Characteristics (continued)
At TA = 25°C, RL = 10 kΩ, VS = 5 V. Unless otherwise specified.
60
130
GAIN
80
PHASE
VS=10V
CL=20 pF 90
20
50
PHASE (q)
VS = 3.3V
CL = 100 pF
60
PHASE (°)
40
GAIN (dB)
Vs = 3.3 V
Vs = 5 V
Vs = 10 V
70
50
40
30
20
0
10
10
VS = 3.3V, 5.0V, 10V
0
CL = 20 pF, 50 pF, 100 pF
-20
10k
100k
1M
-30
10M
1
2
3 4 5 67 10
20 30 50 70100
CLOAD
200
500 1000
D001
Figure 20. Phase Margin vs CL
FREQUENCY (Hz)
Figure 19. Open-Loop Frequency Response Over Load
Conditions
120
3.3V
110
5.0V
100
3.3V
±5V
PSRR (dB)
+PSRR
3.3V
5.0V
±5V
60
40
20
3.3V: VCM = 1V
CMRR (dB)
5.0V
80
90
±5V
70
50
5.0V: VCM = 2.5V
-PSRR
±5V : VCM = 0V
±5V: VCM = 0V
0
100
3.3V : VCM = 1V
5.0V : VCM = 2.5V
30
1k
10k
100k
1M
100
1k
FREQUENCY (Hz)
10k
100k
1M
FREQUENCY (Hz)
Figure 21. PSRR vs Frequency
Figure 22. CMRR vs Frequency
160
140
500 mV/DIV
CHANNEL SEPARATION (dB)
180
120
100
f = 250 kHz
AV = +1
VIN = 2 VPP
CL = 20 pF
80
VS = 3.3V, 5.0V, ±5V
60
100
1k
10k
100k
400 ns/DIV
1M
FREQUENCY (Hz)
Figure 23. Channel Separation vs Frequency
Figure 24. Large Signal Step Response With Gain = 1
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Typical Characteristics (continued)
50 mV/DIV
200 mV/DIV
At TA = 25°C, RL = 10 kΩ, VS = 5 V. Unless otherwise specified.
f = 250 kHz
AV = +1
f = 250 kHz
AV = +10
VIN = 100 mVPP
CL = 20 pF
VIN = 200 mVPP
CL = 20 pF
400 ns/DIV
400 ns/DIV
Figure 25. Large Signal Step Response With Gain = 10
Figure 26. Small Signal Step Response With Gain = 1
20 mV/DIV
SLEW RATE (V/µs)
3.0
f = 250 kHz
AV = +10
VIN = 10 mVPP
CL = 20 pF
FALLING EDGE
2.5
2.0
RISING EDGE
AV = +1
1.5 VIN = 2 VPP
RL = 10 kΩ
CL = 20 pF
1.0
400 ns/DIV
2
4
6
8
10
SUPPLY VOLTAGE (V)
12
Figure 28. Slew Rate vs Supply Voltage
Figure 27. Small Signal Step Response With Gain = 10
35
100
25
50
NOISE (nV/Hz)
OVERSHOOT (%)
30
20
15
10
5.0V
20
V(s) = 3.3 V
V(s) = 5 V
V(s) = ±5 V
5
0
10
3.3V
20
30 40 50 70 100
200 300
CLOAD (pF)
500 700 1000
D002
±5V
10
10
100
1k
10k
100k
FREQUENCY (Hz)
Figure 29. Overshoot vs CL
Figure 30. Input Voltage Noise vs Frequency
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Typical Characteristics (continued)
At TA = 25°C, RL = 10 kΩ, VS = 5 V. Unless otherwise specified.
1
10
VS = 5V
RL = 10 kΩ
AV = +10
0.1
1
VOUT = 4.5 VPP
AV = +10
THD + N (%)
THD + N (%)
CL = 50 pF
0.01
0.1
0.01
AV = +1
VS = 5V
RL = 10 kΩ
CL = 20 pF
f = 1 kHz
AV = +1
0.001
10
100
1k
10k
0.001
0.001
100k
0.01
FREQUENCY (Hz)
0.1
1
10
VOUT (V)
Figure 31. THD+N vs Frequency
Figure 32. THD+N vs VOUT
100
10
ROUT (:)
100x
1
10x
0.1
1x
0.01
0.001
100
1k
10k
100k
1M
10M
FREQUENCY (Hz)
Figure 33. Closed-Loop Output Impedance vs Frequency
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7 Detailed Description
7.1 Overview
The LMV84x devices are operational amplifiers with near-precision specifications: low noise, low temperature
drift, low offset, and rail-to-rail input and output. Possible application areas include instrumentation, medical, test
equipment, audio, and automotive applications.
Its low supply current of 1 mA per amplifier, temperature range of −40°C to +125°C, 12-V supply with CMOS
input, and the small SC70 package for the LMV841 make the LMV84x a unique op amp family and a perfect
choice for portable electronics.
7.2 Functional Block Diagram
7.3 Feature Description
7.3.1 Input Protection
The LMV84x devices have a set of anti-parallel diodes D1 and D2 between the input pins, as shown in Figure 34.
These diodes are present to protect the input stage of the amplifier. At the same time, they limit the amount of
differential input voltage that is allowed on the input pins.
A differential signal larger than one diode voltage drop can damage the diodes. The differential signal between
the inputs needs to be limited to ±300 mV or the input current needs to be limited to ±10 mA.
NOTE
When the op amp is slewing, a differential input voltage exists that forward-biases the
protection diodes. This may result in current being drawn from the signal source. While
this current is already limited by the internal resistors R1 and R2 (both 130 Ω), a resistor of
1 kΩ can be placed in the feedback path, or a 500-Ω resistor can be placed in series with
the input signal for further limitation.
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Feature Description (continued)
V
+
+
V
ESD
IN
IN
ESD
V
+
R1
D1 D2
+
V
ESD
+
-
VOUT
R2
ESD
-
V
-
V
Figure 34. Protection Diodes Between the Input Pins
7.3.2 Input Stage
The input stage of this amplifier consists of both a PMOS and an NMOS input pair to achieve a rail-to-rail input
range. For input voltages close to the negative rail, only the PMOS pair is active. Close to the positive rail, only
the NMOS pair is active. In a transition region that extends from approximately 2 V below V+ to 1 V below V+,
both pairs are active, and one pair gradually takes over from the other. In this transition region, the input-referred
offset voltage changes from the offset voltage associated with the PMOS pair to that of the NMOS pair. The input
pairs are trimmed independently to ensure an input offset voltage of less then 0.5 mV at room temperature over
the complete rail-to-rail input range. This also significantly improves the CMRR of the amplifier in the transition
region.
NOTE
The CMRR and PSRR limits in the tables are large-signal numbers that express the
maximum variation of the input offset of the amplifier over the full common-mode voltage
and supply voltage range, respectively. When the common-mode input voltage of the
amplifier is within the transition region, the small signal CMRR and PSRR may be slightly
lower than the large signal limits.
7.4 Device Functional Modes
7.4.1 Driving Capacitive Load
The LMV84x can be connected as noninverting unity gain amplifiers. This configuration is the most sensitive to
capacitive loading. The combination of a capacitive load placed on the output of an amplifier along with the
output impedance of the amplifier creates a phase lag, which reduces the phase margin of the amplifier. If the
phase margin is significantly reduced, the response is under-damped, which causes peaking in the transfer.
When there is too much peaking, the op amp might start oscillating.
The LMV84x can directly drive capacitive loads up to 100 pF without any stability issues. To drive heavier
capacitive loads, an isolation resistor (RISO) must be used, as shown in Figure 35. By using this isolation resistor,
the capacitive load is isolated from the output of the amplifier, and hence, the pole caused by CL is no longer in
the feedback loop. The larger the value of RISO, the more stable the output voltage is. If values of RISO are
sufficiently large, the feedback loop is stable, independent of the value of CL. However, larger values of RISO
result in reduced output swing and reduced output current drive.
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Device Functional Modes (continued)
RISO
-
V OUT
V IN
+
CL
Figure 35. Isolating Capacitive Load
7.4.2
Noise Performance
The LMV84x devices have good noise specifications and are frequently used in low-noise applications. Therefore
it is important to determine the noise of the total circuit. Besides the input-referred noise of the op amp, the
feedback resistors may have an important contribution to the total noise.
For applications with a voltage input configuration, in general it is beneficial general, beneficial to keep the
resistor values low. In these configurations high resistor values mean high noise levels. However, using low
resistor values will increase the power consumption of the application. This is not always acceptable for portable
applications, so there is a trade-off between noise level and power consumption.
Besides the noise contribution of the signal source, three types of noise need to be taken into account for
calculating the noise performance of an op amp circuit:
• Input-referred voltage noise of the op amp
• Input-referred current noise of the op amp
• Noise sources of the resistors in the feedback network, configuring the op amp
To calculate the noise voltage at the output of the op amp, the first step is to determine a total equivalent noise
source. This requires the transformation of all noise sources to the same reference node. A convenient choice for
this node is the input of the op amp circuit. The next step is to add all the noise sources. The final step is to
multiply the total equivalent input voltage noise with the gain of the op amp configuration.
If the input-referred voltage noise of the op amp is already placed at the input, the user can use the inputreferred voltage noise without further transferring. The input-referred current noise needs to be converted to an
input-referred voltage noise. The current noise is negligibly small, as long as the equivalent resistance is not
unrealistically large, so the user can leave the current noise out for these examples. That leaves the user with
the noise sources of the resistors, being the thermal noise voltage. The influence of the resistors on the total
noise can be seen in the following examples, one with high resistor values and one with low resistor values. Both
examples describe an op amp configuration with a gain of 101 which gives the circuit a bandwidth of 44.5 kHz.
The op amp noise is the same for both cases, that is, an input-referred noise voltage of 20 nV/
and a
negligibly small input-referred noise current.
+
en in
RF
RG
Figure 36. Noise Circuit
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Device Functional Modes (continued)
To calculate the noise of the resistors in the feedback network, the equivalent input-referred noise resistance is
needed. For the example in Figure 36, this equivalent resistance Req can be calculated using Equation 1:
R ´ RG
Req = F
RF + RG
(1)
The voltage noise of the equivalent resistance can be calculated using Equation 2:
enr = 4kTReq
where
•
•
•
•
•
enr = thermal noise voltage of the equivalent resistor
Req (V/ )
k = Boltzmann constant (1.38 x 10–23 J/K)
T = absolute temperature (K)
Req = resistance (Ω)
(2)
The total equivalent input voltage noise is given by Equation 3:
en in = env 2 + enr 2
where
•
•
en in = total input equivalent voltage noise of the circuit
env = input voltage noise of the op amp
(3)
The final step is multiplying the total input voltage noise by the noise gain using Equation 4, which is in this case
the gain of the op amp configuration:
en out = en in ´ Anoise
(4)
The equivalent resistance for the first example with a resistor RF of 10 MΩ and a resistor RG of 100 kΩ at 25°C
(298 K) equals Equation 5:
R ´ RG 10 M W ´ 100 k W
Req = F
=
= 99 k W
RF + RG 10 M W + 100 k W
(5)
Now the noise of the resistors can be calculated using Equation 6, yielding:
enr = 4kTReq
= 4 ´ 1.38 ´ 10-23 J/K ´ 298K ´ 99 k W
= 40 nV/ Hz
(6)
The total noise at the input of the op amp is calculated in Equation 7:
en in = env 2 + enr 2
= (20 nV/ Hz )2 + (40 nV/ Hz )2 = 45 nV/ Hz
(7)
For the first example, this input noise, multiplied with the noise gain, in Equation 8 gives a total output noise of:
en out = en in ´ Anoise
= 45 nV/ Hz ´ 101 = 4.5 mV/ Hz
(8)
In the second example, with a resistor RF of 10 kΩ and a resistor RG of 100 Ω at 25°C (298 K), the equivalent
resistance equals Equation 9:
R ´ RG 10 k W ´ 100 W
Req = F
=
= 99 W
RF + RG 10 k W + 100 W
(9)
The resistor noise for the second example is calculated in Equation 10:
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Device Functional Modes (continued)
enr = 4kTReq
= 4 ´ 1.38 ´ 10-23 J/K ´ 298 K ´ 99 W
= 1 nV/ Hz
(10)
The total noise at the input of the op amp is calculated in Equation 10:
en in = env 2 + enr 2
= (20 nV/ Hz )2 + (1 nV/ Hz )2
= 20 nV/ Hz
(11)
For the second example the input noise, multiplied with the noise gain, in Equation 12 gives an output noise of:
en out = en in ´ Anoise
= 20 nV/ Hz ´ 101 = 2 mV/ Hz
(12)
In the first example the noise is dominated by the resistor noise due to the very high resistor values, in the
second example the very low resistor values add only a negligible contribution to the noise and now the
dominating factor is the op amp itself. When selecting the resistor values, it is important to choose values that do
not add extra noise to the application. Choosing values above 100 kΩ may increase the noise too much. Low
values keep the noise within acceptable levels; choosing very low values however, does not make the noise
even lower, but can increase the current of the circuit.
7.5 Interfacing to High Impedance Sensor
With CMOS inputs, the LMV84x are particularly suited to be used as high impedance sensor interfaces.
Many sensors have high source impedances that may range up to 10 MΩ. The input bias current of an amplifier
loads the output of the sensor, and thus cause a voltage drop across the source resistance, as shown in
Figure 37. When an op amp is selected with a relatively high input bias current, this error may be unacceptable.
The low input current of the LMV84x significantly reduces such errors. The following examples show the
difference between a standard op amp input and the CMOS input of the LMV84x.
The voltage at the input of the op amp can be calculated with Equation 13:
VIN+ = VS – IB × RS
(13)
For a standard op amp, the input bias Ib can be 10 nA. When the sensor generates a signal of 1 V (VS) and the
sensors impedance is 10 MΩ (RS), the signal at the op amp input is calculated in Equation 14:
VIN = 1 V – 10 nA × 10 MΩ = 1 V - 0.1 V = 0.9 V
(14)
For the CMOS input of the LMV84x, which has an input bias current of only 0.3 pA, this would give Equation 15:
VIN = 1 V – 0.3 pA × 10 MΩ = 1 V – 3 µV = 0.999997 V
(15)
The conclusion is that a standard op amp, with its high input bias current input, is not a good choice for use in
impedance sensor applications. The LMV84x devices, in contrast, are much more suitable due to the low input
bias current. The error is negligibly small; therefore, the LMV84x are a must for use with high-impedance
sensors.
SENSOR
RS
VS
+
-
IB
V
VIN+
+
+
-
V
Figure 37. High Impedance Sensor Interface
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8 Application and Implementation
NOTE
Information in the following applications sections is not part of the TI component
specification, and TI does not warrant its accuracy or completeness. TI’s customers are
responsible for determining suitability of components for their purposes. Customers should
validate and test their design implementation to confirm system functionality.
8.1 Application Information
The rail-to-rail input and output of the LMV84x and the wide supply voltage range make these amplifiers ideal to
use in numerous applications. Three sample applications, namely the active filter circuit, high-side current
sensing, and thermocouple sensor interface, are provided in the Typical Applications section.
8.2 Typical Applications
8.2.1 Active Filter Circuit
C
C
R2
R2
R1
C
-
R1
C
-
R3
+
R3
+
Figure 38. Active Band-Pass Filter Implementation
8.2.1.1 Design Requirements
In this example it is required to design a bandpass filter with band-pass frequency of 10 kHz, and a center
frequence of approximately 10% from the total frequence of the filter. This is achieved by cascading two bandpass filters, A and B, with slightly different center frequencies.
8.2.1.2 Detailed Design Procedure
The center frequency of the separate band-pass filters A, and B can be calculated by Equation 16:
fmid =
R1 + R3
1
2pC R1R2R3
where
•
•
•
•
C = 33 nF
R1 = 2 KΩ
R2 = 6.2 KΩ
and R3 = 45 Ω
(16)
This gives Equation 17 for filter A:
fmid =
1
p ´ 33 nF
2 k W + 6.2 k W
= 9.2 kHz
2 k W ´ 6.2 k W ´ 45 k W
(17)
and Equation 18 for filter B with C = 27nF:
fmid =
1
p ´ 27 nF
2 k W + 6.2 k W
= 11.2 kHz
2 k W ´ 6.2 k W ´ 45 k W
(18)
Bandwidth can be calculated by Equation 19:
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Typical Applications (continued)
B=
1
pR2C
(19)
For filter A, this gives Equation 20:
1
= 1.6 kHz
B=
p ´ 6.2 k W ´ 33 nF
(20)
and Equation 21 for filter B:
1
= 1.9 kHz
B=
p ´ 6.2 k W ´ 27 nF
(21)
8.2.1.3 Application Curve
The responses of filter A and filter B are shown as the thin lines in Figure 39; the response of the combined filter
is shown as the thick line. Shifting the center frequencies of the separate filters farther apart, results in a wider
band; however, positioning the center frequencies too far apart results in a less flat gain within the band. For
wider bands more band-pass filters can be cascaded.
10
FILTER A
FILTER B
GAIN (dB)
0
-10
-20
-30
COMBINED
FILTER
-40
1k
10k
100k
FREQUENCY (Hz)
Figure 39. Active Band-Pass Filter Curve
NOTE
Use the WEBENCH internet tools at www.ti.com for your filter application.
8.2.2 High-Side, Current-Sensing Circuit
V
RF
+
RG
RS
+
RG
RF
LOAD
Z
Figure 40. High-Side, Current-Sensing Circuit
22
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Typical Applications (continued)
8.2.2.1 Design Requirements
In this example, it is desired to measure a current between 0 A and 2 A using a sense resistor of 100 mΩ, and
convert it to an output voltage of 0 to 5 V. A current of 2 A flowing through the load and the sense resistor results
in a voltage of 200 mV across the sense resistor. The op amp amplifies this 200 mV to fit the current range to the
output voltage range.
8.2.2.2 Detailed Design Procedure
To measure current at a point in a circuit, a sense resistor is placed in series with the load, as shown in
Figure 40. The current flowing through this sense resistor results in a voltage drop, that is amplified by the op
amp. The rail-to-rail input and the low VOS features make the LMV84x ideal op amps for high-side, currentsensing applications.
The input and the output relation of the circuit is given by Equation 22:
VOUT = RF/RG × VSENSE
(22)
For a load current of 2 A and an output voltage of 5 V the gain would be VOUT / VSENSE = 25.
If the feedback resistor, RF, is 100 kΩ, then the value for RG is 4 kΩ. The tolerance of the resistors has to be low
to obtain a good common-mode rejection.
8.2.3 Thermocouple Sensor Signal Amplification
Figure 41 is a typical example for a thermocouple amplifier application using an LMV841, LMV842, or LMV844. A
thermocouple senses a temperature and converts it into a voltage. This signal is then amplified by the LMV841,
LMV842, or LMV844. An ADC can then convert the amplified signal to a digital signal. For further processing the
digital signal can be processed by a microprocessor, and can be used to display or log the temperature, or the
temperature data can be used in a fabrication process.
Cold junction Temperature
LM35
RF
RG
T
Metal A
Copper
-
RG
LMV841
+
Metal B
Thermocouple
Copper
Amplified
Thermocouple
Output
RF
Cold junction Reference
Figure 41. Thermocouple Sensor Interface
8.2.3.1 Design Requirements
In this example it is desired to measure temperature in the range of 0°C to 500°C with a resolution of 0.5°C using
a K-type thermocouple sensor. The power supply for both the LMV84x and the ADC is
3.3 V.
8.2.3.2 Detailed Design Procedure
A thermocouple is a junction of two different metals. These metals produce a small voltage that increases with
temperature. A K-type thermocouple is a very common temperature sensor made of a junction between nickelchromium and nickel-aluminum. There are several reasons for using the K-type thermocouple. These include
temperature range, the linearity, the sensitivity, and the cost.
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Typical Applications (continued)
A K-type thermocouple has a wide temperature range. The range of this thermocouple is from approximately
−200°C to approximately 1200°C, as can be seen in Figure 42. This covers the generally used temperature
ranges.
Over the main part of the range the behavior is linear. This is important for converting the analog signal to a
digital signal. The K-type thermocouple has good sensitivity when compared to many other types; the sensitivity
is 41 µV/°C. Lower sensitivity requires more gain and makes the application more sensitive to noise. In addition,
a K-type thermocouple is not expensive, many other thermocouples consist of more expensive materials or are
more difficult to produce.
THERMOCOUPLE VOLTAGE (mV)
50
40
30
20
10
0
-10
-200
0
200
400
600
800 1000 1200
TEMPERATURE (°C)
Figure 42. K-Type Thermocouple Response
The temperature range of 0°C to 500°C results in a voltage range from 0 mV to 20.6 mV produced by the
thermocouple. This is shown in Figure 42.
To obtain the best accuracy the full ADC range of 0 to 3.3 V is used and the gain needed for this full range can
be calculated Equation 23:
AV = 3.3 V / 0.0206 V = 160
(23)
If RG is 2 kΩ, then the value for RF can be calculated with this gain of 160. Because AV = RF / RG, RF can be
calculated in Equation 24:
RF = AV × RG = 160 × 2 kΩ = 320 kΩ
(24)
To achieve a resolution of 0.5°C a step smaller than the minimum resolution is needed. This means that at least
1000 steps are necessary (500°C/0.5°C). A 10-bit ADC would be sufficient as this gives 1024 steps. A 10-bit
ADC such as the two channel 10-bit ADC102S021 would be a good choice.
At the point where the thermocouple wires are connected to the circuit on the PCB unwanted parasitic
thermocouple is formed, introducing error in the measurements of the actual thermocouple sensor.
Using an isothermal block as a reference will compensate for this additional thermocouple effect. An isothermal
block is a good heat conductor. This means that the two thermocouple connections both have the same
temperature. The temperature of the isothermal block can be measured, and thereby the temperature of the
thermocouple connections. This is usually called the cold junction reference temperature. In the example, an
LM35 is used to measure this temperature. This semiconductor temperature sensor can accurately measure
temperatures from −55°C to 150°C.
The ADC in this example also coverts the signal from the LM35 to a digital signal, hence, the microprocessor can
compensate for the amplified thermocouple signal of the unwanted thermocouple junction at the connector.
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SNOSAT1I – OCTOBER 2006 – REVISED OCTOBER 2017
9 Power Supply Recommendations
The LMV84x is specified for operation from 2.7 V to 12 V (±1.35 V to ±6 V) over a –40°C to 125°C temperature
range. Parameters that can exhibit significant variance with regard to operating voltage or temperature are
presented in the Absolute Maximum Ratings.
CAUTION
Supply voltages larger than 13.2 V can permanently damage the device.
For proper operation, the power supplies must be properly decoupled. For decoupling the supply lines, TI
suggests placing 10-nF capacitors as close as possible to the operational amplifier power supply pins. For single
supply, place a capacitor between V+ and V– supply leads. For dual supplies, place one capacitor between V+
and ground, and one capacitor between V– and ground.
10 Layout
10.1 Layout Guidelines
•
•
•
•
•
The V+ pin must be bypassed to ground with a low-ESR capacitor.
The optimum placement is closest to the V+ and ground pins.
Take care to minimize the loop area formed by the bypass capacitor connection between V+ and ground.
The ground pin must be connected to the PCB ground plane at the pin of the device.
The feedback components must be placed as close to the device as possible to minimize strays.
10.2 Layout Example
Place components close to
device and to each other to
reduce parasitic error
VOUTA
Place low-ESR ceramic
bypass capacitor close to
device
RF
Run the input traces as
far away from the supply
lines as possible
OUTA
V+
GND
-INA
OUTB
VIN
+INA
-INB
V-
+INB
GND
RG
Place low-ESR ceramic
bypass capacitor close to
device
GND
VS-
Figure 43. Layout Example (Top View)
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11 Device and Documentation Support
11.1 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 1. Related Links
PARTS
PRODUCT FOLDER
ORDER NOW
TECHNICAL
DOCUMENTS
TOOLS &
SOFTWARE
SUPPORT &
COMMUNITY
LMV841
Click here
Click here
Click here
Click here
Click here
LMV842
Click here
Click here
Click here
Click here
Click here
LMV844
Click here
Click here
Click here
Click here
Click here
11.2 Receiving Notification of Documentation Updates
To receive notification of documentation updates, navigate to the device product folder on ti.com. In the upper
right corner, click on Alert me to register and receive a weekly digest of any product information that has
changed. For change details, review the revision history included in any revised document.
11.3 Community Resources
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of
Use.
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help
solve problems with fellow engineers.
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and
contact information for technical support.
11.4 Trademarks
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
11.5 Electrostatic Discharge Caution
These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam
during storage or handling to prevent electrostatic damage to the MOS gates.
11.6 Glossary
SLYZ022 — TI Glossary.
This glossary lists and explains terms, acronyms, and definitions.
12 Mechanical, Packaging, and Orderable Information
The following pages include mechanical, packaging, and orderable information. This information is the most
current data available for the designated devices. This data is subject to change without notice and revision of
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.
26
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PACKAGE OPTION ADDENDUM
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10-Dec-2020
PACKAGING INFORMATION
Orderable Device
Status
(1)
Package Type Package Pins Package
Drawing
Qty
Eco Plan
(2)
Lead finish/
Ball material
MSL Peak Temp
Op Temp (°C)
Device Marking
(3)
(4/5)
(6)
LMV841MG/NOPB
ACTIVE
SC70
DCK
5
1000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
A97
LMV841MGX/NOPB
ACTIVE
SC70
DCK
5
3000
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
A97
LMV842MA/NOPB
ACTIVE
SOIC
D
8
95
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
LMV84
2MA
LMV842MAX/NOPB
ACTIVE
SOIC
D
8
2500
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
LMV84
2MA
LMV842MM/NOPB
ACTIVE
VSSOP
DGK
8
1000
RoHS & Green
NIPDAUAG | SN
Level-1-260C-UNLIM
-40 to 125
AC4A
LMV842MMX/NOPB
ACTIVE
VSSOP
DGK
8
3500
RoHS & Green
NIPDAUAG | SN
Level-1-260C-UNLIM
-40 to 125
AC4A
LMV844MA/NOPB
ACTIVE
SOIC
D
14
55
RoHS & Green
Call TI | SN
Level-1-260C-UNLIM
-40 to 125
LMV844MA
LMV844MAX/NOPB
ACTIVE
SOIC
D
14
2500
RoHS & Green
Call TI | SN
Level-1-260C-UNLIM
-40 to 125
LMV844MA
LMV844MT/NOPB
ACTIVE
TSSOP
PW
14
94
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
LMV844
MT
LMV844MTX/NOPB
ACTIVE
TSSOP
PW
14
2500
RoHS & Green
SN
Level-1-260C-UNLIM
-40 to 125
LMV844
MT
(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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