110 100 10k 100k
FREQUENCY (Hz)
1
10
100
1k
VOLTAGE NOISE (nV/
Hz)
V+ = 5.5V
V+ = 2.5V
CCM
IIN
RF
VOUT
+
-
+
-
VB
CF
CD
VOUT
IIN - RF
=
CIN = CD + CCM
Product
Folder
Sample &
Buy
Technical
Documents
Tools &
Software
Support &
Community
LMV791
,
LMV792
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
LMV79x 17-MHz, Low-Noise, CMOS Input, 1.8-V Operational Amplifiers With Shutdown
1 Features 3 Description
The LMV791 (single) and the LMV792 (dual) low-
1Typical 5-V Supply, Unless Otherwise Noted noise, CMOS input operational amplifiers offer a low
• Input Referred Voltage Noise 5.8 nV/√Hz input voltage noise density of 5.8 nV/√Hz while
• Input Bias Current 100 fA consuming only 1.15 mA (LMV791) of quiescent
current. The LMV791 and LMV792 are unity gain
• Unity Gain Bandwidth 17 MHz stable operational amplifiers and have gain bandwidth
• Supply Current per Channel Enable Mode of 17 MHz. The LMV79x have a supply voltage range
– LMV791 1.15 mA of 1.8 V to 5.5 V and can operate from a single
supply. The LMV79x each feature a rail-to-rail output
– LMV792 1.30 mA stage capable of driving a 600-Ωload and sourcing
• Supply Current per Channel in Shutdown Mode as much as 60 mA of current.
0.02 µA The LMV79x family provides optimal performance in
• Rail-to-Rail Output Swing low-voltage and low-noise systems. A CMOS input
– At 10-kΩLoad, 25 mV from Rail stage, with typical input bias currents in the range of
– At 2-kΩLoad, 45 mV from Rail a few femtoamperes, and an input common-mode
voltage range which includes ground, make the
• Ensured 2.5-V and 5-V Performance LMV791 and the LMV792 ideal for low-power sensor
• Total Harmonic Distortion 0.01% at1 kHz, 600 Ωapplications. The LMV79x family has a built-in enable
• Temperature Range −40°C to 125°C feature which can be used to optimize power
dissipation in low power applications.
2 Applications The LMV791x are manufactured using TI’s advanced
• Photodiode Amplifiers VIP50 process and are offered in a 6-pin SOT and a
10-pin VSSOP package respectively.
• Active Filters and Buffers
• Low-Noise Signal Processing Device Information(1)
• Medical Instrumentation PART NUMBER PACKAGE BODY SIZE (NOM)
• Sensor Interface Applications LMV791 SOT (6) 2.90 mm × 1.60 mm
LMV792 VSSOP (10) 3.00 mm × 3.00 mm
(1) For all available packages, see the orderable addendum at
the end of the data sheet.
Photodiode Transimpedance Amplifier Low-Noise CMOS Input
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.
LMV791
,
LMV792
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
www.ti.com
Table of Contents
7.4 Device Functional Modes........................................ 17
1 Features.................................................................. 18 Application and Implementation ........................ 19
2 Applications ........................................................... 18.1 Application Information............................................ 19
3 Description............................................................. 18.2 Typical Applications ............................................... 19
4 Revision History..................................................... 29 Power Supply Recommendations...................... 24
5 Pin Configuration and Functions......................... 310 Layout................................................................... 24
6 Specifications......................................................... 410.1 Layout Guidelines ................................................. 24
6.1 Absolute Maximum Ratings ...................................... 410.2 Layout Example .................................................... 24
6.2 ESD Ratings.............................................................. 411 Device and Documentation Support................. 25
6.3 Recommended Operating Conditions....................... 411.1 Device Support .................................................... 25
6.4 Thermal Information.................................................. 411.2 Documentation Support ....................................... 25
6.5 2.5-V Electrical Characteristics ................................ 511.3 Related Links ........................................................ 25
6.6 5-V Electrical Characteristics ................................... 611.4 Community Resources.......................................... 25
6.7 Typical Characteristics.............................................. 811.5 Trademarks........................................................... 25
7 Detailed Description............................................ 16 11.6 Electrostatic Discharge Caution............................ 25
7.1 Overview................................................................. 16 11.7 Glossary................................................................ 26
7.2 Functional Block Diagram....................................... 16 12 Mechanical, Packaging, and Orderable
7.3 Feature Description................................................. 16 Information ........................................................... 26
4 Revision History
NOTE: Page numbers for previous revisions may differ from page numbers in the current version.
Changes from Revision F (March 2013) to Revision G Page
• Added Pin Configuration and Functions section, 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
• Updated the format of the Enable and Shutdown Pin Voltage Range in the 2.5-V Electrical Characteristics table for
clarity ...................................................................................................................................................................................... 5
• Updated the format of the Enable and Shutdown Pin Voltage Range in the 5-V Electrical Characteristics table for clarity. 7
Changes from Revision E (March 2013) to Revision F Page
• Changed layout of National Data Sheet to TI format ........................................................................................................... 23
2Submit Documentation Feedback Copyright © 2005–2015, Texas Instruments Incorporated
Product Folder Links: LMV791 LMV792
OUT A
IN A-
IN A+
V-
EN A
1
2
3
4
5EN B
IN B+
IN B-
OUT B
V+
6
7
8
9
10
+
-
+
-
OUTPUT
V-
+IN
V+
-IN
+-
1
2
3
5
4
6
EN
LMV791
,
LMV792
www.ti.com
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
5 Pin Configuration and Functions
LMV791 DDC Package
6-Pin SOT
Top View
Pin Functions—LMV791
PIN I/O DESCRIPTION
NAME NO.
EN 5 I Enable
+IN 3 I Noninverting Input
–IN 4 I Inverting Input
Out 1 O Output
V+ 6 P Positive (highest) Supply Voltage
V– 2 P Negative (lowest) Supply Voltage
LMV792 DGS Package
10-Pin VSSOP
Top View
Pin Functions—LMV792
PIN I/O DESCRIPTION
NAME NO.
EN A 5 I Enable A
EN B 6 I Enable B
IN A+ 3, 7 I Inverting Input
IN A– 2, 8 I Noninverting Input
Out 1 O Output B
Out B 9 O Output B
V+ 10 P Positive (highest) Supply Voltage
V– 4 P Negative (lowest) Supply Voltage
Copyright © 2005–2015, Texas Instruments Incorporated Submit Documentation Feedback 3
Product Folder Links: LMV791 LMV792
LMV791
,
LMV792
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
www.ti.com
6 Specifications
6.1 Absolute Maximum Ratings
See (1)(2)
MIN MAX UNIT
VIN differential ±0.3 V
Supply voltage (V+– V−) 6 V
Input/Output pin voltage V++ 0.3 V−−0.3 V
Junction temperature(3) 150 °C
Infrared or convection (20 sec) 235 °C
Soldering
information Wave soldering lead temperature (10 sec) 260 °C
Storage temperature, Tstg −65 150 °C
(1) 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.
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments Sales Office/Distributors for availability and
specifications.
(3) The maximum power dissipation is a function of TJ(MAX),θJA. The maximum allowable power dissipation at any ambient temperature is
PD= (TJ(MAX) - TA)/θJA. All numbers apply for packages soldered directly onto a PCB.
6.2 ESD Ratings VALUE UNIT
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001(1)(2) ±2000
Electrostatic
V(ESD) Charged-device model (CDM), per JEDEC specification JESD22-C101(3) ±1000 V
discharge Machine model(4) ±200
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.
(2) Human Body Model is 1.5 kΩin series with 100 pF.
(3) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.
(4) Machine Model is 0 Ωin series with 200 pF
6.3 Recommended Operating Conditions MIN MAX UNIT
Temperature(1) −40 125 °C
−40°C ≤TJ≤125°C 2 5.5 V
Supply voltage
(V+– V−)0°C ≤TJ≤125°C 1.8 5.5 V
(1) The maximum power dissipation is a function of TJ(MAX),θJA. The maximum allowable power dissipation at any ambient temperature is
PD= (TJ(MAX) - TA)/θJA. All numbers apply for packages soldered directly onto a PCB.
6.4 Thermal Information LMV791 LMV792
THERMAL METRIC(1) DDC (SOT-23) DGS (VSSOP) UNIT
6 PINS 10 PINS
RθJA Junction-to-ambient thermal resistance(2) 191.8 179.1 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 68.1 70.5 °C/W
RθJB Junction-to-board thermal resistance 36.9 99.7 °C/W
ψJT Junction-to-top characterization parameter 2.2 11.6 °C/W
ψJB Junction-to-board characterization parameter 36.5 98.2 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application
report, SPRA953.
(2) The maximum power dissipation is a function of TJ(MAX),θJA. The maximum allowable power dissipation at any ambient temperature is
PD= (TJ(MAX) - TA)/θJA. All numbers apply for packages soldered directly onto a PCB.
4Submit Documentation Feedback Copyright © 2005–2015, Texas Instruments Incorporated
Product Folder Links: LMV791 LMV792
LMV791
,
LMV792
www.ti.com
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
6.5 2.5-V Electrical Characteristics
Unless otherwise specified, all limits are ensured for TJ= 25°C, V+= 2.5 V, V−= 0 V, VCM = V+/2 = VO, VEN = V+.
PARAMETER TEST CONDITIONS MIN(1) TYP(2) MAX(1) UNIT
TJ= 25 °C 0.1 ±1.35
VOS Input offset voltage mV
−40°C ≤TJ≤125°C ±1.65
LMV791(3) −1
TC VOS Input offset voltage temperature drift μV/°C
LMV792(3) −1.8
TJ= 25 °C 0.05 1
IBInput bias current VCM = 1 V(4) (5) −40°C ≤TJ≤85 °C 25 pA
−40°C ≤TJ≤125 °C 100
IOS Input offset current VCM = 1 V(5) 10 fA
TJ= 25 °C 80 94
CMRR Common-mode rejection ratio 0 V ≤VCM ≤1.4 V dB
−40°C ≤TJ≤125°C 75
TJ= 25 °C 80 100
2.0V ≤V+≤5.5V, VCM = 0
V−40°C ≤TJ≤125°C 75
PSRR Power supply rejection ratio dB
80 98
1.8 V ≤V+≤5.5 V, VCM = 0 V
CMRR ≥60 dB TJ= 25 °C −0.3 1.5
CMVR Common-mode voltage range V
CMRR ≥55 dB −40°C ≤TJ≤125°C −0.3 1.5
TJ= 25 °C 85 98
LMV791 −40°C ≤TJ≤125°C 80
VOUT = 0.15 V to 2.2 V,
RLOAD = 2 kΩto V+/2 TJ= 25 °C 82 92
AVOL Open-loop voltage gain LMV792 dB
−40°C ≤TJ≤125°C 78
TJ= 25 °C 88 110
VOUT = 0.15 V to 2.2 V,
RLOAD = 10 kΩto V+/2 −40°C ≤TJ≤125°C 84
TJ= 25 °C 25 75
RLOAD = 2 kΩto V+/2 −40°C ≤TJ≤125°C 82
Output voltage swing high TJ= 25 °C 20 65
RLOAD = 10 kΩto V+/2 −40°C ≤TJ≤125°C 71 mV from
VOUT either rail
TJ= 25 °C 30 75
RLOAD = 2 kΩto V+/2 −40°C ≤TJ≤125°C 78
Output voltage swing low TJ= 25 °C 15 65
RLOAD = 10 kΩto V+/2 −40°C ≤TJ≤125°C 67
TJ= 25 °C 35 47
Sourcing to V−
VIN = 200 mV(6) −40°C ≤TJ≤125°C 28
IOUT Output current mA
TJ= 25 °C 7 15
Sinking to V+
VIN = –200 mV(6) −40°C ≤TJ≤125°C 5
TJ= 25 °C 0.95 1.3
LMV791 −40°C ≤TJ≤125°C 1.65
Enable mode mA
VEN ≥2.1 V TJ= 25 °C 1.1 1.50
LMV792
ISSupply current per amplifier per channel −40°C ≤TJ≤125°C 1.85
Shutdown mode, VEN < TJ= 25 °C 0.02 1
0.4 μA
−40°C ≤TJ≤125°C 5
per channel
AV= +1, Rising (10% to 90%) 8.5
SR Slew rate V/μs
AV= +1, Falling (90% to 10%) 10.5
GBW Gain bandwidth 14 MHz
enInput referred voltage noise density f = 1 kHz 6.2 nV/√Hz
inInput referred current noise density f = 1 kHz 0.01 pA/√Hz
ton Turnon time 140 ns
toff Turnoff time 1000 ns
Enable mode 2.1 2
VEN Enable pin voltage range V
Shutdown mode 0.5 0.4
(1) Limits are 100% production tested at 25°C. Limits over the operating temperature range are ensured through correlations using the
statistical quality control (SQC) method.
(2) Typical values represent the parametric norm at the time of characterization.
(3) Offset voltage average drift is determined by dividing the change in VOS by temperature change.
(4) Positive current corresponds to current flowing into the device.
(5) This parameter is specified by design and/or characterization and is not tested in production.
(6) The short circuit test is a momentary test, the short circuit duration is 1.5 ms.
Copyright © 2005–2015, Texas Instruments Incorporated Submit Documentation Feedback 5
Product Folder Links: LMV791 LMV792
LMV791
,
LMV792
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
www.ti.com
2.5-V Electrical Characteristics (continued)
Unless otherwise specified, all limits are ensured for TJ= 25°C, V+= 2.5 V, V−= 0 V, VCM = V+/2 = VO, VEN = V+.
PARAMETER TEST CONDITIONS MIN(1) TYP(2) MAX(1) UNIT
Enable mode VEN = 2.5 V(4) 1.5 3
IEN Enable pin input current μA
Shutdown mode VEN = 0 V(4) 0.003 0.1
THD+N Total harmonic distortion + noise f = 1 kHz, AV= 1, RLOAD = 600 Ω0.01%
6.6 5-V Electrical Characteristics
Unless otherwise specified, all limits are ensured for TJ= 25°C, V+= 5 V, V−= 0 V, VCM = V+/2 = VO, VEN = V+.
PARAMETER TEST CONDITIONS MIN(1) TYP(2) MAX(1) UNIT
TJ= 25 °C 0.1 ±1.35
VOS Input offset voltage mV
−40°C ≤TJ≤125°C ±1.65
LMV791(3) −1
TC VOS Input offset voltage temperature drift μV/°C
LMV792(3) −1.8
TJ= 25 °C 0.1 1
IBInput bias current VCM = 2 V(4) (5) −40°C ≤TJ≤85°C 25 pA
−40°C ≤TJ≤125°C 100
IOS Input offset current VCM = 2 V(5) 10 fA
TJ= 25 °C 80 100
CMRR Common-mode rejection ratio 0 V ≤VCM ≤3.7 V dB
−40°C ≤TJ≤125°C 75
TJ= 25 °C 80 100
2.0V ≤V+≤5.5 V, VCM =
0 V −40°C ≤TJ≤125°C 75
PSRR Power supply rejection ratio dB
80 98
1.8V ≤V+≤5.5 V, VCM = 0 V
CMRR ≥60 dB TJ= 25 °C −0.3 4
CMVR Common-mode voltage range V
CMRR ≥55 dB −40°C ≤TJ≤125°C −0.3 4
TJ= 25 °C 85 97
LMV791 −40°C ≤TJ≤125°C 80
VOUT = 0.3V to 4.7V,
RLOAD = 2 kΩto V+/2 TJ= 25 °C 82 89
AVOL Open-loop voltage gain LMV792 dB
−40°C ≤TJ≤125°C 78
TJ= 25 °C 88 110
VOUT = 0.3V to 4.7V,
RLOAD = 10 kΩto V+/2 −40°C ≤TJ≤125°C 84
TJ= 25 °C 35 75
RLOAD = 2 kΩto V+/2 −40°C ≤TJ≤125°C 82
Output voltage swing high TJ= 25 °C 25 65
RLOAD = 10 kΩto V+/2 −40°C ≤TJ≤125°C 71
TJ= 25 °C 42 75 mV from
VOUT LMV791 either rail
−40°C ≤TJ≤125°C 78
RLOAD = 2 kΩto V+/2 TJ= 25 °C 45 80
Output voltage swing low LMV792 −40°C ≤TJ≤125°C 83
TJ= 25 °C 20 65
RLOAD = 10 kΩto V+/2 −40°C ≤TJ≤125°C 67
TJ= 25 °C 45 60
Sourcing to V−
VIN = 200 mV(6) −40°C ≤TJ≤125°C 37
IOUT Output current mA
TJ= 25 °C 10 21
Sinking to V+
VIN = –200 mV(6) −40°C ≤TJ≤125°C 6
TJ= 25 °C 1.15 1.4
LMV791 −40°C ≤TJ≤125°C 1.75
Enable mode mA
VEN ≥4.6 V TJ= 25 °C 1.3 1.7
LMV792
ISSupply current per amplifier per channel −40°C ≤TJ≤125°C 2.05
TJ= 25 °C 0.14 1
Shutdown mode (VEN ≤μA
0.4 V) −40°C ≤TJ≤125°C 5
(1) Limits are 100% production tested at 25°C. Limits over the operating temperature range are ensured through correlations using the
statistical quality control (SQC) method.
(2) Typical values represent the parametric norm at the time of characterization.
(3) Offset voltage average drift is determined by dividing the change in VOS by temperature change.
(4) Positive current corresponds to current flowing into the device.
(5) This parameter is specified by design and/or characterization and is not tested in production.
(6) The short circuit test is a momentary test, the short circuit duration is 1.5 ms.
6Submit Documentation Feedback Copyright © 2005–2015, Texas Instruments Incorporated
Product Folder Links: LMV791 LMV792
LMV791
,
LMV792
www.ti.com
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
5-V Electrical Characteristics (continued)
Unless otherwise specified, all limits are ensured for TJ= 25°C, V+= 5 V, V−= 0 V, VCM = V+/2 = VO, VEN = V+.
PARAMETER TEST CONDITIONS MIN(1) TYP(2) MAX(1) UNIT
AV= +1, Rising (10% to 90%) 6 9.5
SR Slew rate V/μs
AV= +1, Falling (90% to 10%) 7.5 11.5
GBW Gain bandwidth 17 MHz
enInput referred voltage noise density f = 1 kHz 5.8 nV/√Hz
inInput referred current noise density f = 1 kHz 0.01 pA/√Hz
ton Turnon time 110 ns
toff Turnoff time 800 ns
Enable mode 4.6 4.5
VEN Enable pin voltage range V
Shutdown mode 0.5 0.4
Enable mode VEN = 5 V(4) 5.6 10
IEN Enable pin input current μA
Shutdown mode VEN = 0 V(4) 0.005 0.2
THD+N Total harmonic distortion + noise f = 1 kHz, AV= 1, RLOAD = 600 Ω0.01%
Copyright © 2005–2015, Texas Instruments Incorporated Submit Documentation Feedback 7
Product Folder Links: LMV791 LMV792
1.5 2.5 3.5 4.5 5.5
0
1
1.2
1.4
1.6
1.8
SUPPLY CURRENT (PA)
V+ (V)
0.8
0.6
0.4
0.2
125°C
25°C
-40°C
6.0
1.5 2.5 3.5 4.5 5.5 6
0
0.4
0.8
1.2
1.6
2
SUPPLY CURRENT (mA)
V+ (V)
25°C
-40°C
125°C
1.5 2.5 3.5 4.5 5.5 6.0
SUPPLY CURRENT (mA)
V+ (V)
0
0.4
0.8
1.2
1.6
2
25°C
-40°C
125°C
LMV791
,
LMV792
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
www.ti.com
6.7 Typical Characteristics
Unless otherwise specified, TA= 25°C, V–= 0, V+= Supply Voltage = 5V, VCM = V+/2, VEN = V+.
Figure 1. Supply Current vs Supply Voltage (LMV791) Figure 2. Supply Current vs Supply Voltage (LMV792)
Figure 3. Supply Current vs Figure 4. VOS vs VCM
Supply Voltage in Shutdown Mode
Figure 5. VOS vs VCM Figure 6. VOS vs VCM
8Submit Documentation Feedback Copyright © 2005–2015, Texas Instruments Incorporated
Product Folder Links: LMV791 LMV792
0 0.5 1 1.5 2 2.5
-0.1
0.1
0.3
0.5
0.7
0.9
1.1
1.3
1.5
1.7
SUPPLY CURRENT (mA)
ENABLE PIN VOLTAGE (V)
125°C
-40°C
25°C
V+ = 2.5V
0 1 2 3 4 5
-0.1
0.4
0.9
1.4
1.9
2.4
SUPPLY CURRENT (mA)
ENABLE PIN VOLTAGE (V)
125°C
-40°C
25°C
V+ = 5V
-40°C
125°C
25°C
-40°C
25°C
125°C
0 0.5 1 1.5 2 2.5
-0.1
0.1
0.3
0.5
0.7
0.9
1.5
SUPPLY CURRENT (mA)
ENABLE PIN VOLTAGE (V)
1.1
1.3 V+ = 2.5V
0 1 2 3 4 5
-0.1
0.4
0.9
1.4
1.9
2.4
SUPPLY CURRENT (mA)
ENABLE PIN VOLTAGE (V)
125°C
25°C
-40°C
-40°C
125°C
V+ = 5V
1.5 2.5 3.5 4.5 5.5 6.0
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
VOS (mV)
V+ (V)
-40°C
125°C
25°C
13
SLEW RATE (V/Ps)
1.8 2.3 2.8 3.3 3.8 4.3 4.8 5.3
6
7
8
9
10
11
V+ (V)
12
RISING
FALLING
5.5
LMV791
,
LMV792
www.ti.com
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
Typical Characteristics (continued)
Unless otherwise specified, TA= 25°C, V–= 0, V+= Supply Voltage = 5V, VCM = V+/2, VEN = V+.
Figure 8. Slew Rate vs Supply Voltage
Figure 7. VOS vs Supply Voltage
Figure 10. Supply Current vs Enable Pin Voltage(LMV791)
Figure 9. Supply Current vs Enable Pin Voltage (LMV791)
Figure 11. Supply Current vs Enable Pin Voltage (LMV792) Figure 12. Supply Current vs Enable Pin Voltage (LMV792)
Copyright © 2005–2015, Texas Instruments Incorporated Submit Documentation Feedback 9
Product Folder Links: LMV791 LMV792
0 1 2 3 4 5
0
5
10
15
20
25
30
ISINK (mA)
VOUT (V)
125°C
25°C
-40°C
-40°C
0 1 2 3 4 5
0
10
20
30
40
50
60
70
ISOURCE (mA)
VOUT (V)
125°C
25°C
1 2 3 4 5 6
0
10
20
30
40
50
60
70
80
ISOURCE (mA)
V+ (V)
125°C
25°C
-40°C
1 2 3 4 5 6
0
5
10
15
20
25
30
35
ISINK (mA)
V+ (V)
25°C
125°C
-40°C
0 1 2 3 4
-50
50
IBIAS (pA)
VCM (V)
-40
-30
-20
-10
0
10
20
30
40
125°C
V+ = 5V
85°C
LMV791
,
LMV792
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
www.ti.com
Typical Characteristics (continued)
Unless otherwise specified, TA= 25°C, V–= 0, V+= Supply Voltage = 5V, VCM = V+/2, VEN = V+.
Figure 13. Input Bias Current vs VCM Figure 14. Input Bias Current vs VCM
Figure 15. Sourcing Current vs Supply Voltage Figure 16. Sinking Current vs Supply Voltage
Figure 17. Sourcing Current vs Output Voltage Figure 18. Sinking Current vs Output Voltage
10 Submit Documentation Feedback Copyright © 2005–2015, Texas Instruments Incorporated
Product Folder Links: LMV791 LMV792
1.8 2.5 3.2 3.9 4.6 5.3 6
V+ (V)
0
20
40
60
80
100
120
VOUT FROM RAIL (mV)
RLOAD = 600:
-40°C
25°C 125°C
1.8 2.5 3.2 3.9 4.6 5.3 6
0
10
20
30
40
50
60
70
80
90
100
VOUT FROM RAIL (mV)
V+ (V)
125°C
25°C
-40°C
RLOAD = 600:
1.8 2.5 3.2 3.9 4.6 5.3 6
0
5
10
15
20
25
30
35
40
45
50
VOUT FROM RAIL (mV)
V+ (V)
125°C
25°C
-40°C
RLOAD = 2 k:
125°C
25°C
-40°C
0
10
20
30
40
45
50
VOUT FROM RAIL (mV)
5
15
25
35
1.8 2.5 3.2 3.9 4.6 5.3 6
V+ (V)
RLOAD = 2 k:
1.8 2.5 3.2 3.9 4.6 5.3 6
V+ (V)
0
5
10
15
20
25
VOUT FROM RAIL (mV)
-40°C
25°C
125°C
RLOAD = 10 k:
1.8 2.5 3.2 3.9 4.6 5.3 6
V+ (V)
0
5
10
15
20
25
30
35
40
VOUT FROM RAIL (mV)
125°C
25°C
-40°C
RLOAD = 10 k:
LMV791
,
LMV792
www.ti.com
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
Typical Characteristics (continued)
Unless otherwise specified, TA= 25°C, V–= 0, V+= Supply Voltage = 5V, VCM = V+/2, VEN = V+.
Figure 19. Positive Output Swing vs Supply Voltage Figure 20. Negative Output Swing vs Supply Voltage
Figure 22. Negative Output Swing vs Supply Voltage
Figure 21. Positive Output Swing vs Supply Voltage
Figure 23. Positive Output Swing vs Supply Voltage Figure 24. Negative Output Swing vs Supply Voltage
Copyright © 2005–2015, Texas Instruments Incorporated Submit Documentation Feedback 11
Product Folder Links: LMV791 LMV792
0.02 0.2 2
OUTPUT AMPLITUDE (V)
-140
-120
-100
-80
-60
-40
-20
0
THD+N (dB)
V+ = 2.75V
V- = -2.75V
AV = +2
RLOAD = 100 k:
RLOAD = 600:
4
10 100 1k 10k 100k
FREQUENCY (Hz)
0
0.001
0.002
0.003
0.004
0.005
0.006
THD+N (%)
RL = 600:
RL = 100 k:
V+ = 1.2V
V- = 0.6V
VO = 0.9 VPP
AV = +2
OUTPUT AMPLITUDE (V)
0.02 0.2 2
-120
-100
-80
-60
-40
-20
0
THD+N (dB)
RLOAD = 600:
RLOAD = 100 k:
V+ = 1.2V
V- = -0.6V
AV = +2
020 40 60 80 100 120
CLOAD (pF)
0
10
20
30
40
50
60
70
OVERSHOOT AND UNDERSHOOT %
US%
OS%
400 nV/DIV
1S/DIV
VS = ±2.5V
VCM = 0.0V
110 100 10k 100k
FREQUENCY (Hz)
1
10
100
1k
VOLTAGE NOISE (nV/
Hz)
V+ = 5.5V
V+ = 2.5V
LMV791
,
LMV792
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
www.ti.com
Typical Characteristics (continued)
Unless otherwise specified, TA= 25°C, V–= 0, V+= Supply Voltage = 5V, VCM = V+/2, VEN = V+.
Figure 25. Input Referred Voltage Noise vs Frequency Figure 26. Time Domain Voltage Noise
Figure 27. Overshoot and Undershoot vs CLOAD Figure 28. THD+N vs Peak-to-Peak Output Voltage (VOUT)
Figure 30. THD+N vs Frequency
Figure 29. THD+N vs Peak-to-Peak Output Voltage (VOUT)
12 Submit Documentation Feedback Copyright © 2005–2015, Texas Instruments Incorporated
Product Folder Links: LMV791 LMV792
160
1k 100k 100M
FREQUENCY (Hz)
0
60
CROSSTALK REJECTION RATION (dB)
10M
1M
10k
120
100
40
20
80
140
10 mV/DIV
200 ns/DIV
INPUT = 20 mVPP
f = 1 MHz
V+ = 2.5V
-40
-20
0
20
60
80
100
120
GAIN (dB)
40
-60
PHASE (°)
-40
-20
0
20
60
80
100
120
40
-60
FREQUENCY (Hz)
10k 100k 1M 10M 100M
PHASE
GAIN
RLOAD = 600:10k: 10 M:
10 1k 10k 100k 1M 10M 100M
FREQUENCY (Hz)
0.01
0.1
1
10
100
OUTPUT IMPEDANCE (:)
100
10 100 1k 10k 100k
FREQUENCY (Hz)
0
0.001
0.002
0.003
0.004
0.005
0.006
THD+N (%)
RL = 600:
RL = 100 k:
V+ = 2.5V
V- = 2.5V
VO = 4 VPP
AV = +2
1k 10k 100k 1M 10M 100M
-40
-20
0
20
60
80
100
120
GAIN (dB)
FREQUENCY (Hz)
40
-60
PHASE (°)
-40
-20
0
20
60
80
100
120
40
-60
CL = 20 pF
CL = 50 pF
CL = 100 pF
GAIN
CL = 100 pF
CL = 50 pF
CL = 20 pF
PHASE
LMV791
,
LMV792
www.ti.com
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
Typical Characteristics (continued)
Unless otherwise specified, TA= 25°C, V–= 0, V+= Supply Voltage = 5V, VCM = V+/2, VEN = V+.
Figure 32. Open-Loop Gain and Phase With Capacitive Load
Figure 31. THD+N vs Frequency
Figure 34. Closed-Loop Output Impedance vs Frequency
Figure 33. Open-Loop Gain and Phase With Resistive Load
AV= +1 Figure 36. Small Signal Transient Response
Figure 35. Crosstalk Rejection
Copyright © 2005–2015, Texas Instruments Incorporated Submit Documentation Feedback 13
Product Folder Links: LMV791 LMV792
-10
0
10
20
30
40
50
PHASE MARGIN (°)
10 100 1000
CLOAD (pF)
RLOAD = 10 M:
V+ = 5V
RLOAD = 10 k:
RLOAD = 600:
10 1k 100k 10M
FREQUENCY (Hz)
-100
-60
-40
0
POSITIVE PSRR (dB)
1M10k
100
-20
-80 1.8V
5.5V
-10
0
10
20
30
40
50
PHASE MARGIN (°)
10 100 1000
CLOAD (pF)
RLOAD = 10 M:
V+ = 2.5V
RLOAD = 10 k:
RLOAD = 600:
200 mV/DIV
800 ns/DIV
INPUT = 1 VPP
f = 200 kHz
V+ = 5V
800 ns/DIV
200 mV/DIV
INPUT = 1 VPP
f = 200 kHz
V+ = 2.5V
10 mV/DIV
200 ns/DIV
INPUT = 20 mVPP
f = 1 MHz
V+ = 5V
LMV791
,
LMV792
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
www.ti.com
Typical Characteristics (continued)
Unless otherwise specified, TA= 25°C, V–= 0, V+= Supply Voltage = 5V, VCM = V+/2, VEN = V+.
AV= +1 AV= +1
Figure 37. Large Signal Transient Response Figure 38. Small Signal Transient Response
AV= +1 Figure 40. Phase Margin vs Capacitive Load (Stability)
Figure 39. Large Signal Transient Response
Figure 42. Positive PSRR vs Frequency
Figure 41. Phase Margin vs Capacitive Load (Stability)
14 Submit Documentation Feedback Copyright © 2005–2015, Texas Instruments Incorporated
Product Folder Links: LMV791 LMV792
0 1 2 3 4
0
5
10
15
20
25
CCM (pF)
VCM (V)
V+ = 5V
10 1k 1M
FREQUENCY (Hz)
0
40
120
CMRR (dB)
100k
10k
100
100
60
20
80
V+ = 2.5V
V+ = 5V
-120
-100
-80
-60
-40
-20
NEGATIVE PSRR (dB)
10 100 1k 10k 100k 1M 10M
FREQUENCY (Hz)
V+ = 1.8V
V+ = 5.5V
LMV791
,
LMV792
www.ti.com
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
Typical Characteristics (continued)
Unless otherwise specified, TA= 25°C, V–= 0, V+= Supply Voltage = 5V, VCM = V+/2, VEN = V+.
Figure 43. Negative PSRR vs Frequency Figure 44. CMRR vs Frequency
Figure 45. Input Common-Mode Capacitance vs VCM
Copyright © 2005–2015, Texas Instruments Incorporated Submit Documentation Feedback 15
Product Folder Links: LMV791 LMV792
LMV791
,
LMV792
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
www.ti.com
7 Detailed Description
7.1 Overview
The LMV79x family provides optimal performance in low-voltage and low-noise systems. A low-noise CMOS
input stage, with typical input bias currents in the range of a few femtoamperes, and an input common-mode
voltage range which includes ground make the LMV791 and the LMV792 ideal for low-power sensor applications
7.2 Functional Block Diagram
7.3 Feature Description
7.3.1 Wide Bandwidth at Low Supply Current
The LMV791 and LMV792 are high performance operational amplifiers that provide a unity gain bandwidth of 17
MHz while drawing a low supply current of 1.15 mA. This makes them ideal for providing wideband amplification
in portable applications. The shutdown feature can also be used to design more power efficient systems that
offer wide bandwidth and high performance while consuming less average power.
7.3.2 Low Input Referred Noise and Low Input Bias Current
The LMV79x have a very low input referred voltage noise density (5.8 nV/√Hz at 1 kHz). A CMOS input stage
ensures a small input bias current (100 fA) and low input referred current noise (0.01 pA/√Hz). This is very
helpful in maintaining signal fidelity, and makes the LMV791 and LMV792 ideal for audio and sensor-based
applications.
7.3.3 Low Supply Voltage
The LMV791 and the LMV792 have performance ensured at 2.5-V and 5-V supply. The LMV791 family is
ensured to be operational at all supply voltages between 2 V and 5.5 V, for ambient temperatures ranging from
−40°C to 125°C, thus using the entire battery lifetime. The LMV791 and LMV792 are also ensured to be
operational at 1.8-V supply voltage, for temperatures between 0°C and 125°C. This makes the LMV791 family
ideal for usage in low-voltage commercial applications.
7.3.4 Rail-to-Rail Output and Ground Sensing
Rail-to-rail output swing provides maximum possible dynamic range at the output. This is particularly important
when operating at low supply voltages. An innovative positive feedback scheme is used to boost the current drive
capability of the output stage. This allows the LMV791 and the LMV792 to source more than 40 mA of current at
1.8-V supply. This also limits the performance of the LMV791 family as comparators, and hence the usage of the
LMV791 and the LMV792 in an open-loop configuration is not recommended. The input common-mode range
includes the negative supply rail which allows direct sensing at ground in single supply operation.
7.3.5 Shutdown Feature
The LMV791 family is ideal for battery-powered systems. With a low supply current of 1.15 mA and a shutdown
current of 140 nA typically, the LMV791 and LMV792 allow the designer to maximize battery life. The enable pin
of the LMV791 and the LMV792 allows the operational amplifier to be turned off and reduce its supply current to
less than 1 μA. To power on the operational amplifier the enable pin should be higher than V+– 0.5 V, where V+
is the positive supply. To disable the operational amplifier, the enable pin voltage should be less than V−+ 0.5 V,
where V−is the negative supply.
16 Submit Documentation Feedback Copyright © 2005–2015, Texas Instruments Incorporated
Product Folder Links: LMV791 LMV792
CIN
R1
R2
VOUT
+
-
+
-
VIN
+
-
VOUT
VIN
R2
R1
AV = - = -
CF
LMV791
,
LMV792
www.ti.com
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
Feature Description (continued)
7.3.6 Small Size
The small footprint of the LMV791 and the LMV792 package saves space on printed-circuit-boards, and enables
the design of smaller electronic products, such as mobile phones, tablets, or other portable systems. Long traces
between the signal source and the operational amplifier make the signal path susceptible to noise. By using a
physically smaller LMV791 and LMV792 package, the operational amplifier can be placed closer to the signal
source, reducing noise pick-up and increasing signal integrity.
7.4 Device Functional Modes
7.4.1 Capacitive Load Tolerance
The LMV791 and LMV792 can directly drive up to 120 pF in unity gain without oscillation. The unity gain follower
is the most sensitive configuration to capacitive loading. Direct capacitive loading reduces the phase margin of
amplifiers. The combination of the output impedance of the amplifier and the capacitive load induces phase lag.
This results in either an underdamped pulse response or oscillation. To drive a heavier capacitive load, the circuit
in Figure 46 can be used.
In Figure 46, the isolation resistor RISO and the load capacitor CLform a pole to increase stability by adding more
phase margin to the overall system. The desired performance depends on the value of RISO. The bigger the RISO
resistor value, the more stable VOUT will be. Increased RISO would, however, result in a reduced output swing and
short circuit current.
Figure 46. Isolation of CLto Improve Stability
7.4.2 Input Capacitance and Feedback Circuit Elements
The LMV791 family has a very low input bias current (100 fA) and a low 1/f noise corner frequency (400 Hz),
which makes it ideal for sensor applications. However, to obtain this performance a large CMOS input stage is
used, which adds to the input capacitance of the operational amplifier, CIN. Though this does not affect the DC
and low frequency performance, at higher frequencies the input capacitance interacts with the input and the
feedback impedances to create a pole, which results in lower phase margin and gain peaking. This can be
controlled by being selective in the use of feedback resistors, as well as by using a feedback capacitance, CF.
For example, in the inverting amplifier shown in Figure 47, if CIN and CFare ignored and the open-loop gain of
the operational amplifier is considered infinite then the gain of the circuit is −R2/R1. An operational amplifier,
however, usually has a dominant pole, which causes its gain to drop with frequency. Hence, this gain is only
valid for DC and low frequency. To understand the effect of the input capacitance coupled with the non-ideal gain
of the operational amplifier, the circuit needs to be analyzed in the frequency domain using a Laplace transform.
Figure 47. Inverting Amplifier
Copyright © 2005–2015, Texas Instruments Incorporated Submit Documentation Feedback 17
Product Folder Links: LMV791 LMV792
10k 100k 1M 10M 100M
FREQUENCY (Hz)
-25
-20
-15
-10
-5
0
5
10
15
GAIN (dB)
R1, R2 = 30 k:
AV = -1
R1, R2 = 10 k:
R1, R2 = 1 k:
10k 100k 1M 10M
FREQUENCY (Hz)
-40
-30
-20
-10
0
10
20
GAIN (dB)
CF = 0 pF
CF = 5 pF
CF = 2 pF
R1, R2 = 30 k:
AV = -1
+¨
©
§
¨
©
§
-1
2CIN
P1,2 = 1
R1
1
R2r1
R1
1
R2
+
2
-4 A0CIN
R2
-R2/R1
1 + s
¨
©
§
¨
©
§
+s2
A0
CIN R2
¨
©
§
¨
©
§
VOUT
VIN (s) =
A0 R1
R1 + R2
LMV791
,
LMV792
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
www.ti.com
Device Functional Modes (continued)
For simplicity, the operational amplifier is modeled as an ideal integrator with a unity gain frequency of A0.
Hence, its transfer function (or gain) in the frequency domain is A0/s. Solving the circuit equations in the
frequency domain, ignoring CFfor the moment, results in an expression for the gain shown in Equation 1.
(1)
It can be inferred from the denominator of the transfer function that it has two poles, whose expressions can be
obtained by solving for the roots of the denominator and are shown in Equation 2.
(2)
Equation 2 shows that as the values of R1and R2are increased, the magnitude of the poles, and hence the
bandwidth of the amplifier, is reduced. This theory is verified by using different values of R1and R2in the circuit
shown in Figure 46 and by comparing their frequency responses. In Figure 48 the frequency responses for three
different values of R1and R2are shown. When both R1and R2are 1 kΩ, the response is flattest and widest;
whereas, it narrows and peaks significantly when both their values are changed to 10 kΩor 30 kΩ. So it is
advisable to use lower values of R1and R2to obtain a wider and flatter response. Lower resistances also help in
high-sensitivity circuits because they add less noise.
A way of reducing the gain peaking is by adding a feedback capacitance CFin parallel with R2. This introduces
another pole in the system and prevents the formation of pairs of complex conjugate poles which cause the gain
to peak. Figure 49 shows the effect of CFon the frequency response of the circuit. Adding a capacitance of 2 pF
removes the peak, while a capacitance of 5 pF creates a much lower pole and reduces the bandwidth
excessively.
Figure 48. Gain Peaking Caused by Large R1, R2Figure 49. Gain Peaking Eliminated by CF
18 Submit Documentation Feedback Copyright © 2005–2015, Texas Instruments Incorporated
Product Folder Links: LMV791 LMV792
CCM
IIN
RF
VOUT
+
-
+
-
VB
CF
CD
VOUT
IIN - RF
=
CIN = CD + CCM
LMV791
,
LMV792
www.ti.com
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
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 LMV791 and LMV792 family of amplifiers is specified for operation from 1.8 V to 5.5 V. Parameters that can
exhibit significant variance with regard to operating voltage or temperature are presented in the Typical
Characteristics section.
8.2 Typical Applications
These application examples highlight a few of the circuits where the LMV791 and LMV792 may be used.
8.2.1 Transimpedance Amplifier
CMOS input operational amplifiers are often used in transimpedance applications as they have an extremely high
input impedance. A transimpedance amplifier converts a small input current into a voltage. This current is usually
generated by a photodiode. The transimpedance gain, measured as the ratio of the output voltage to the input
current, is expected to be large and wide-band. Because the circuit deals with currents in the range of a few nA,
low-noise performance is essential. The LMV79x are CMOS input operational amplifiers providing wide
bandwidth and low noise performance, and are hence ideal for transimpedance applications.
Figure 50. Photodiode Transimpedance Amplifier
8.2.1.1 Design Requirements
Usually, a transimpedance amplifier is designed on the basis of the current source driving the input. A
photodiode is a very common capacitive current source, which requires transimpedance gain for transforming its
miniscule current into easily-detectable voltages. The photodiode and gain of the amplifier are selected with
respect to the speed and accuracy required of the circuit. A faster circuit would require a photodiode with lesser
capacitance and a faster amplifier. A more sensitive circuit would require a sensitive photodiode and a high gain.
A typical transimpedance amplifier is shown in Figure 50. The output voltage of the amplifier is given by the
equation VOUT =−IINRF. Because the output swing of the amplifier is limited, RFshould be selected such that all
possible values of IIN can be detected.
Copyright © 2005–2015, Texas Instruments Incorporated Submit Documentation Feedback 19
Product Folder Links: LMV791 LMV792
OP AMP
OPEN LOOP
GAIN
NOISE GAIN WITH NO CF
NOISE GAIN WITH CF
fZfPA0
fZ = 1
2SRFCIN
fP = A0
2SRF(CIN+CF)
GAIN
FREQUENCY
RFCINA0
CF = 2SRFA0
1 + 1 + 4S
LMV791
,
LMV792
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
www.ti.com
Typical Applications (continued)
8.2.1.2 Detailed Design Procedure
The LMV79x have a large gain-bandwidth product (17 MHz), which enables high gains at wide bandwidths. A
rail-to-rail output swing at 5.5-V supply allows detection and amplification of a wide range of input currents. A
CMOS input stage with negligible input current noise and low input voltage noise allows the LMV79x to provide
high-fidelity amplification for wide bandwidths. These properties make the LMV79x ideal for systems requiring
wide-band transimpedance amplification.
As mentioned earlier, the following parameters are used to design a transimpedance amplifier: the amplifier gain-
bandwidth product, A0; the amplifier input capacitance, CCM; the photodiode capacitance, CD; the
transimpedance gain required, RF; and the amplifier output swing. Once a feasible RFis selected using the
amplifier output swing, these numbers can be used to design an amplifier with the desired transimpedance gain
and a maximally flat frequency response.
An essential component for obtaining a maximally flat response is the feedback capacitor, CF. The capacitance
seen at the input of the amplifier, CIN, combined with the feedback capacitor, RF, generate a phase lag which
causes gain-peaking and can destabilize the circuit. CIN is usually just the sum of CDand CCM. The feedback
capacitor CFcreates a pole, fPin the noise gain of the circuit, which neutralizes the zero in the noise gain, fZ,
created by the combination of RFand CIN. If properly positioned, the noise gain pole created by CFcan ensure
that the slope of the gain remains at 20 dB/decade till the unity gain frequency of the amplifier is reached, thus
ensuring stability. As shown in Figure 51, fPis positioned such that it coincides with the point where the noise
gain intersects the open-loop gain of the operational amplifier. In this case, fPis also the overall 3-dB frequency
of the transimpedance amplifier. The value of CFneeded to make it so is given by Equation 3. A larger value of
CFcauses excessive reduction of bandwidth, while a smaller value fails to prevent gain peaking and instability.
(3)
Figure 51. CFSelection for Stability
Calculating CFfrom Equation 3 can sometimes return unreasonably small values (<1 pF), especially for high-
speed applications. In these cases, its often more practical to use the circuit shown in Figure 52 in order to allow
more reasonable values. In this circuit, the capacitance CF′is (1+ RB/RA) time the effective feedback capacitance,
CF. A larger capacitor can now be used in this circuit to obtain a smaller effective capacitance.
For example, if a CFof 0.5 pF is needed, while only a 5-pF capacitor is available, RBand RAcan be selected
such that RB/RA= 9. This would convert a CF′of 5 pF into a CFof 0.5 pF. This relationship holds as long as RA<
RF.
20 Submit Documentation Feedback Copyright © 2005–2015, Texas Instruments Incorporated
Product Folder Links: LMV791 LMV792
10k 100k 1M 10M
FREQUENCY (Hz)
50
60
70
80
90
100
110
120
130
GAIN (dB)
CIN = 50 pF, CF = 1.5 pF
CIN = 100 pF, CF = 2 pF
CIN = 200 pF, CF = 3 pF
10k 100k 1M 10M
FREQUENCY (Hz)
50
55
60
65
70
75
80
85
90
95
100
GAIN (dB)
CIN = 50 pF, CF = 4.5 pF
CIN = 100 pF, CF = 6 pF
CIN = 200 pF, CF = 9 pF
+
RF
-
CF
IF RA < < RF
CFc = ¨
©
§1 + RB
RA
¨
©
§
RA
CFc
RB
LMV791
,
LMV792
www.ti.com
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
Typical Applications (continued)
Figure 52. Obtaining Small CFfrom large CF′
8.2.2 Application Curves
The LMV791 was used to design a number of amplifiers with varying transimpedance gains and source
capacitances. The gains, bandwidths and feedback capacitances of the circuits created are summarized in
Table 1. The frequency responses are presented in Figure 53 and Figure 54. The feedback capacitances are
slightly different from the formula in Equation 3, because the parasitic capacitance of the board and the feedback
resistor RFhad to be accounted for.
Table 1. Frequency Response Results
Transimpedance, ATI CIN CF3-dB Frequency
470000 50 pF 1.5 pF 350 kHz
470000 100 pF 2.0 pF 250 kHz
470000 200 pF 3.0 pF 150 kHz
47000 50 pF 4.5 pF 1.5 MHz
47000 100 pF 6.0 pF 1 MHz
47000 200 pF 9.0 pF 700 kHz
Figure 54. Frequency Response for ATI = 47000
Figure 53. Frequency Response for ATI = 470000
Copyright © 2005–2015, Texas Instruments Incorporated Submit Documentation Feedback 21
Product Folder Links: LMV791 LMV792
10k 100k 1M 10M
FREQUENCY (Hz)
60
70
80
90
100
110
120
GAIN (dB)
CIN = 50 pF
CF = 4.5 pF
+
-
+
-
792B
792A
CIN = 50 pF
47 k:
4.5 pF
1 k:
0.1 PF
10 k:
+
-
VOUT
IIN
VOUT
IIN = 470,000
ATI =
LMV791
,
LMV792
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
www.ti.com
8.2.3 High-Gain, Wideband Transimpedance Amplifier Using the LMV792
The LMV792, dual, low-noise, wide-bandwidth, CMOS input operational amplifier IC can be used for compact,
robust and integrated solutions for sensing and amplifying wide-band signals obtained from sensitive
photodiodes. One of the two operational amplifiers available can be used to obtain transimpedance gain while
the other can be used for amplifying the output voltage to further enhance the transimpedance gain. The wide
bandwidth of the operational amplifiers (17 MHz) ensures that they are capable of providing high gain for a wide
range of frequencies. The low input referred noise (5.8 nV/√Hz) allows the amplifier to deliver an output with a
high SNR (signal to noise ratio). The small VSSOP-10 footprint saves space on printed-circuit-boards and allows
ease of design in portable products.
The circuit shown in Figure 55, has the first operational amplifier acting as a transimpedance amplifier with a gain
of 47000, while the second stage provides a voltage gain of 10. This provides a total transimpedance gain of
470000 with a −3-dB bandwidth of about 1.5 MHz, for a total input capacitance of 50 pF. The frequency
response for the circuit is shown in Figure 56
Figure 55. 1.5-MHz Transimpedance Amplifier, With ATI = 470000
Figure 56. 1.5-MHz Transimpedance Amplifier Frequency Response
8.2.4 Audio Preamplifier With Bandpass Filtering
With low input referred voltage noise, low supply voltage and low supply current, and a low harmonic distortion,
the LMV791 family is ideal for audio applications. Its wide unity gain bandwidth allows it to provide large gain for
a wide range of frequencies and it can be used to design a preamplifier to drive a load of as low as 600 Ωwith
less than 0.01% distortion. Two amplifier circuits are shown in Figure 57 and Figure 58.Figure 57 is an inverting
amplifier, with a 10-kΩfeedback resistor, R2, and a 1-kΩinput resistor, R1, and hence provides a gain of −10.
Figure 58 is a noninverting amplifier, using the same values of R1and R2, and provides a gain of 11. In either of
these circuits, the coupling capacitor CC1 decides the lower frequency at which the circuit starts providing gain,
while the feedback capacitor CFdecides the frequency at which the gain starts dropping off. Figure 59 shows the
frequency response of the inverting amplifier with different values of CF.
22 Submit Documentation Feedback Copyright © 2005–2015, Texas Instruments Incorporated
Product Folder Links: LMV791 LMV792
+
VOUT
+
-
-
RACF
VIN = KI
+
-
IR RADIATION
INTENSITY, I
VOUT RA
K(RA + RB)
I =
IR SENSOR
RB
25
1100 10k 1M
FREQUENCY (Hz)
-20
-5
10
GAIN (dB)
100k1k
10
20
15
5
0
-10
-15
CF = 10 pF
CF = 100 pF
CF = 1 nF
CC2 RB1
RB2
CF
CC1
V+
AV = 1 + R2
R1
+
-
VIN
+
-
R1
1 k:
R2
10 k:
VOUT
+
-
= 11
CC1
+VOUT
+
-
-
CF
VIN
+
-
RB1
V+
RB2
CC2
R2
R1
AV = - = -10
R2
10 k:
R1
1 k:
LMV791
,
LMV792
www.ti.com
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
Figure 57. Inverting Audio Preamplifier Figure 58. Noninverting Audio Preamplifier
Figure 59. Frequency Response of the Inverting Audio Preamplifier
8.2.5 Sensor Interfaces
The low input bias current and low input referred noise of the LMV791 and LMV792 make them ideal for sensor
interfaces. These circuits are required to sense voltages of the order of a few μV, and currents amounting to less
than a nA, and hence the operational amplifier needs to have low voltage noise and low input bias current.
Typical applications include infrared (IR) thermometry, thermocouple amplifiers and pH electrode buffers.
Figure 60 is an example of a typical circuit used for measuring IR radiation intensity, often used for estimating the
temperature of an object from a distance. The IR sensor generates a voltage proportional to I, which is the
intensity of the IR radiation falling on it. As shown in Figure 60, K is the constant of proportionality relating the
voltage across the IR sensor (VIN) to the radiation intensity, I. The resistances RAand RBare selected to provide
a high gain to amplify this voltage, while CFis added to filter out the high-frequency noise.
Figure 60. IR Radiation Sensor
Copyright © 2005–2015, Texas Instruments Incorporated Submit Documentation Feedback 23
Product Folder Links: LMV791 LMV792
LMV791
,
LMV792
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
www.ti.com
9 Power Supply Recommendations
For proper operation, the power supplies must be properly decoupled. For decoupling the supply lines, TI
recommends that 10-nF capacitors be placed 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
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 single-supply applications.
Noise can propagate into analog circuitry through the power pins of the circuit as a whole and operational
amplifier itself. Bypass capacitors are used to reduce the coupled noise by providing low-impedance power
sources local to the analog circuitry.
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.
The ground pin should be connected to the PCB ground plane at the pin of the device.
The feedback components should be placed as close to the device as possible minimizing strays.
10.2 Layout Example
Figure 61. Typical SOT Layout
24 Submit Documentation Feedback Copyright © 2005–2015, Texas Instruments Incorporated
Product Folder Links: LMV791 LMV792
LMV791
,
LMV792
www.ti.com
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
11 Device and Documentation Support
11.1 Device Support
11.1.1 Development Support
For developmental support, see the following:
• LMV791 PSPICE Model, SNOM056
• LMV792 PSPICE Model, SNOM057
• TINA-TI SPICE-Based Analog Simulation Program, http://www.ti.com/tool/tina-ti
• DIP Adapter Evaluation Module, http://www.ti.com/tool/dip-adapter-evm
• TI Universal Operational Amplifier Evaluation Module, http://www.ti.com/tool/opampevm
• TI Filterpro Software, http://www.ti.com/tool/filterpro
11.2 Documentation Support
11.2.1 Related Documentation
For related documentation, see the following:
•AN-31 Op Amp Circuit Collection,SNLA140
•Feedback Plots Define Op Amp AC Performance, SBOA015 (AB-028)
•Circuit Board Layout Techniques, SLOA089
•Op Amps for Everyone, SLOD006
•Capacitive Load Drive Solution using an Isolation Resistor, TIPD128
•Handbook of Operational Amplifier Applications, SBOA092
11.3 Related Links
The table below lists quick access links. Categories include technical documents, support and community
resources, tools and software, and quick access to sample or buy.
Table 2. Related Links
TECHNICAL TOOLS & SUPPORT &
PARTS PRODUCT FOLDER SAMPLE & BUY DOCUMENTS SOFTWARE COMMUNITY
LMV791 Click here Click here Click here Click here Click here
LMV792 Click here Click here Click here Click here Click here
11.4 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.
11.5 Trademarks
E2E is a trademark of Texas Instruments.
All other trademarks are the property of their respective owners.
11.6 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.
Copyright © 2005–2015, Texas Instruments Incorporated Submit Documentation Feedback 25
Product Folder Links: LMV791 LMV792
LMV791
,
LMV792
SNOSAG6G –SEPTEMBER 2005–REVISED OCTOBER 2015
www.ti.com
11.7 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 Submit Documentation Feedback Copyright © 2005–2015, Texas Instruments Incorporated
Product Folder Links: LMV791 LMV792
PACKAGE OPTION ADDENDUM
www.ti.com 28-Feb-2017
Addendum-Page 1
PACKAGING INFORMATION
Orderable Device Status
(1)
Package Type Package
Drawing Pins Package
Qty Eco Plan
(2)
Lead/Ball Finish
(6)
MSL Peak Temp
(3)
Op Temp (°C) Device Marking
(4/5)
Samples
LMV791MK/NOPB ACTIVE SOT-23-THIN DDC 6 1000 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 AS1A
LMV791MKX/NOPB ACTIVE SOT-23-THIN DDC 6 3000 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 AS1A
LMV792MM/NOPB ACTIVE VSSOP DGS 10 1000 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 AX2A
LMV792MMX/NOPB ACTIVE VSSOP DGS 10 3500 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM AX2A
(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) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability
information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that
lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between
the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight
in homogeneous material)
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation
of the previous line and the two combined represent the entire Device Marking for that device.
(6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish
value exceeds the maximum column width.
PACKAGE OPTION ADDENDUM
www.ti.com 28-Feb-2017
Addendum-Page 2
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device Package
Type Package
Drawing Pins SPQ Reel
Diameter
(mm)
Reel
Width
W1 (mm)
A0
(mm) B0
(mm) K0
(mm) P1
(mm) W
(mm) Pin1
Quadrant
LMV791MK/NOPB SOT-
23-THIN DDC 6 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3
LMV791MKX/NOPB SOT-
23-THIN DDC 6 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3
LMV792MM/NOPB VSSOP DGS 10 1000 178.0 12.4 5.3 3.4 1.4 8.0 12.0 Q1
LMV792MMX/NOPB VSSOP DGS 10 3500 330.0 12.4 5.3 3.4 1.4 8.0 12.0 Q1
PACKAGE MATERIALS INFORMATION
www.ti.com 3-Mar-2017
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
LMV791MK/NOPB SOT-23-THIN DDC 6 1000 210.0 185.0 35.0
LMV791MKX/NOPB SOT-23-THIN DDC 6 3000 210.0 185.0 35.0
LMV792MM/NOPB VSSOP DGS 10 1000 210.0 185.0 35.0
LMV792MMX/NOPB VSSOP DGS 10 3500 367.0 367.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 3-Mar-2017
Pack Materials-Page 2
IMPORTANT NOTICE
Texas Instruments Incorporated (TI) reserves the right to make corrections, enhancements, improvements and other changes to its
semiconductor products and services per JESD46, latest issue, and to discontinue any product or service per JESD48, latest issue. Buyers
should obtain the latest relevant information before placing orders and should verify that such information is current and complete.
TI’s published terms of sale for semiconductor products (http://www.ti.com/sc/docs/stdterms.htm) apply to the sale of packaged integrated
circuit products that TI has qualified and released to market. Additional terms may apply to the use or sale of other types of TI products and
services.
Reproduction of significant portions of TI information in TI data sheets is permissible only if reproduction is without alteration and is
accompanied by all associated warranties, conditions, limitations, and notices. TI is not responsible or liable for such reproduced
documentation. Information of third parties may be subject to additional restrictions. Resale of TI products or services with statements
different from or beyond the parameters stated by TI for that product or service voids all express and any implied warranties for the
associated TI product or service and is an unfair and deceptive business practice. TI is not responsible or liable for any such statements.
Buyers and others who are developing systems that incorporate TI products (collectively, “Designers”) understand and agree that Designers
remain responsible for using their independent analysis, evaluation and judgment in designing their applications and that Designers have
full and exclusive responsibility to assure the safety of Designers' applications and compliance of their applications (and of all TI products
used in or for Designers’ applications) with all applicable regulations, laws and other applicable requirements. Designer represents that, with
respect to their applications, Designer has all the necessary expertise to create and implement safeguards that (1) anticipate dangerous
consequences of failures, (2) monitor failures and their consequences, and (3) lessen the likelihood of failures that might cause harm and
take appropriate actions. Designer agrees that prior to using or distributing any applications that include TI products, Designer will
thoroughly test such applications and the functionality of such TI products as used in such applications.
TI’s provision of technical, application or other design advice, quality characterization, reliability data or other services or information,
including, but not limited to, reference designs and materials relating to evaluation modules, (collectively, “TI Resources”) are intended to
assist designers who are developing applications that incorporate TI products; by downloading, accessing or using TI Resources in any
way, Designer (individually or, if Designer is acting on behalf of a company, Designer’s company) agrees to use any particular TI Resource
solely for this purpose and subject to the terms of this Notice.
TI’s provision of TI Resources does not expand or otherwise alter TI’s applicable published warranties or warranty disclaimers for TI
products, and no additional obligations or liabilities arise from TI providing such TI Resources. TI reserves the right to make corrections,
enhancements, improvements and other changes to its TI Resources. TI has not conducted any testing other than that specifically
described in the published documentation for a particular TI Resource.
Designer is authorized to use, copy and modify any individual TI Resource only in connection with the development of applications that
include the TI product(s) identified in such TI Resource. NO OTHER LICENSE, EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE
TO ANY OTHER TI INTELLECTUAL PROPERTY RIGHT, AND NO LICENSE TO ANY TECHNOLOGY OR INTELLECTUAL PROPERTY
RIGHT OF TI OR ANY THIRD PARTY IS GRANTED HEREIN, including but not limited to any patent right, copyright, mask work right, or
other intellectual property right relating to any combination, machine, or process in which TI products or services are used. Information
regarding or referencing third-party products or services does not constitute a license to use such products or services, or a warranty or
endorsement thereof. Use of TI Resources may require a license from a third party under the patents or other intellectual property of the
third party, or a license from TI under the patents or other intellectual property of TI.
TI RESOURCES ARE PROVIDED “AS IS” AND WITH ALL FAULTS. TI DISCLAIMS ALL OTHER WARRANTIES OR
REPRESENTATIONS, EXPRESS OR IMPLIED, REGARDING RESOURCES OR USE THEREOF, INCLUDING BUT NOT LIMITED TO
ACCURACY OR COMPLETENESS, TITLE, ANY EPIDEMIC FAILURE WARRANTY AND ANY IMPLIED WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NON-INFRINGEMENT OF ANY THIRD PARTY INTELLECTUAL
PROPERTY RIGHTS. TI SHALL NOT BE LIABLE FOR AND SHALL NOT DEFEND OR INDEMNIFY DESIGNER AGAINST ANY CLAIM,
INCLUDING BUT NOT LIMITED TO ANY INFRINGEMENT CLAIM THAT RELATES TO OR IS BASED ON ANY COMBINATION OF
PRODUCTS EVEN IF DESCRIBED IN TI RESOURCES OR OTHERWISE. IN NO EVENT SHALL TI BE LIABLE FOR ANY ACTUAL,
DIRECT, SPECIAL, COLLATERAL, INDIRECT, PUNITIVE, INCIDENTAL, CONSEQUENTIAL OR EXEMPLARY DAMAGES IN
CONNECTION WITH OR ARISING OUT OF TI RESOURCES OR USE THEREOF, AND REGARDLESS OF WHETHER TI HAS BEEN
ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
Unless TI has explicitly designated an individual product as meeting the requirements of a particular industry standard (e.g., ISO/TS 16949
and ISO 26262), TI is not responsible for any failure to meet such industry standard requirements.
Where TI specifically promotes products as facilitating functional safety or as compliant with industry functional safety standards, such
products are intended to help enable customers to design and create their own applications that meet applicable functional safety standards
and requirements. Using products in an application does not by itself establish any safety features in the application. Designers must
ensure compliance with safety-related requirements and standards applicable to their applications. Designer may not use any TI products in
life-critical medical equipment unless authorized officers of the parties have executed a special contract specifically governing such use.
Life-critical medical equipment is medical equipment where failure of such equipment would cause serious bodily injury or death (e.g., life
support, pacemakers, defibrillators, heart pumps, neurostimulators, and implantables). Such equipment includes, without limitation, all
medical devices identified by the U.S. Food and Drug Administration as Class III devices and equivalent classifications outside the U.S.
TI may expressly designate certain products as completing a particular qualification (e.g., Q100, Military Grade, or Enhanced Product).
Designers agree that it has the necessary expertise to select the product with the appropriate qualification designation for their applications
and that proper product selection is at Designers’ own risk. Designers are solely responsible for compliance with all legal and regulatory
requirements in connection with such selection.
Designer will fully indemnify TI and its representatives against any damages, costs, losses, and/or liabilities arising out of Designer’s non-
compliance with the terms and provisions of this Notice.
Mailing Address: Texas Instruments, Post Office Box 655303, Dallas, Texas 75265
Copyright © 2017, Texas Instruments Incorporated
Mouser Electronics
Authorized Distributor
Click to View Pricing, Inventory, Delivery & Lifecycle Information:
Texas Instruments:
LMV791MK LMV791MK/NOPB LMV791MKX LMV791MKX/NOPB LMV792MM LMV792MMX LMV796MFX
LMV797MM LMV797MMX