LMP2231
www.ti.com
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
LMP2231 Single Micropower, 1.6V, Precision Operational Amplifier with CMOS Inputs
Check for Samples: LMP2231
1FEATURES DESCRIPTION
The LMP2231 is a single micropower precision
23(For VS= 5V, TA= 25°C, Typical Unless amplifier designed for battery powered applications.
Otherwise Noted) The 1.6V to 5.5V operating supply voltage range and
• Supply Current 10 µA quiescent power consumption of only 16 μW extend
• Operating Voltage Range 1.6V to 5.5V the battery life in portable battery operated systems.
The LMP2231 is part of the LMP™ precision amplifier
• TCVOS (LMP2231A) ±0.4 µV/°C (max) family. The high impedance CMOS input makes it
• TCVOS (LMP2231B) ±2.5µV/°C (max) ideal for instrumentation and other sensor interface
• VOS ±150 µV (max) applications.
• Input Bias Current 20 fA The LMP2231 has a maximum offset of 150 µV and
• PSRR 120 dB maximum offset voltage drift of only 0.4 µV/°C along
with low bias current of only ±20 fA. These precise
• CMRR 97 dB specifications make the LMP2231 a great choice for
• Open Loop Gain 120 dB maintaining system accuracy and long term stability.
• Gain Bandwidth Product 130 kHz The LMP2231 has a rail-to-rail output that swings 15
• Slew Rate 58 V/ms mV from the supply voltage, which increases system
• Input Voltage Noise, f = 1 kHz 60 nV/√Hz dynamic range. The common mode input voltage
range extends 200 mV below the negative supply,
• Temperature Range –40°C to 125°C thus the LMP2231 is ideal for use in single supply
applications with ground sensing.
APPLICATIONS The LMP2231 is offered in 5-Pin SOT-23 and 8-pin
• Precision Instrumentation Amplifiers SOIC packages.
• Battery Powered Medical Instrumentation The dual and quad versions of this product are also
• High Impedance Sensors available. The dual, LMP2232 is offered in 8-pin
• Strain Gauge Bridge Amplifier SOIC and VSSOP. The quad, LMP2234 is offered in
14-pin SOIC and TSSOP.
• Thermocouple Amplifiers
1Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
2LMP is a trademark of Texas Instruments.
3All other trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Copyright © 2008–2013, Texas Instruments Incorporated
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
ADC121S021
IN
V+
LM4140A
6
2
1,4,7,8
3
V+
1 PF
+
-
0.1 PF
10 PF
VA
V+
+
-
+
-
-
+
12 k:
10 k:40 k:
½
LMP2232
R+'R
R+'R
R
R
V+
V+
V+
12 k:
10 k:40 k:
1 k:LMP2231
½
LMP2232
LMP2231
GND
LMP2231
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
www.ti.com
Typical Application
Figure 1. Strain Gauge Bridge Amplifier
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.
Absolute Maximum Ratings(1)(2)
ESD Tolerance (3) Human Body Model 2000V
Machine Model 100V
Differential Input Voltage ±300 mV
Supply Voltage (VS= V+- V–) 6V
Voltage on Input/Output Pins V++ 0.3V, V–– 0.3V
Storage Temperature Range −65°C to 150°C
Junction Temperature (4) 150°C
For soldering specifications: see product folder at www.ti.com and http://www.ti.com/lit/SNOA549.
(1) Absolute Maximum Ratings indicate limits beyond which damage may occur. Operating Ratings indicate conditions for which the device
is intended to be functional, but specific performance is not ensured. For ensured specifications and test conditions, see the Electrical
Characteristics.
(2) If Military/Aerospace specified devices are required, please contact the TI Sales Office/ Distributors for availability and specifications.
(3) Human Body Model, applicable std. MIL-STD-883, Method 3015.7. Machine Model, applicable std. JESD22-A115-A (ESD MM std. of
JEDEC)Field-Induced Charge-Device Model, applicable std. JESD22-C101-C (ESD FICDM std. of JEDEC).
(4) 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 PC Board.
2Submit Documentation Feedback Copyright © 2008–2013, Texas Instruments Incorporated
Product Folder Links: LMP2231
LMP2231
www.ti.com
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
Operating Ratings(1)
Operating Temperature Range (2) −40°C to 125°C
Supply Voltage (VS= V+- V−) 1.6V to 5.5V
Package Thermal Resistance (θJA)(2) 5-Pin SOT-23 160.6 °C/W
8-Pin SOIC 116.2 °C/W
(1) Absolute Maximum Ratings indicate limits beyond which damage may occur. Operating Ratings indicate conditions for which the device
is intended to be functional, but specific performance is not ensured. For ensured specifications and test conditions, see the Electrical
Characteristics.
(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 PC Board.
5V DC Electrical Characteristics(1)
Unless otherwise specified, all limits ensured for TA= 25°C, V+= 5V, V−= 0V, VCM = VO= V+/2, and RL> 1 MΩ.Boldface
limits apply at the temperature extremes.
Symbol Parameter Conditions Min(2) Typ(3) Max(2) Units
VOS Input Offset Voltage ±10 ±150 μV
±230
TCVOS Input Offset Voltage Drift LMP2231A ±0.3 ±0.4 μV/°C
LMP2231B ±0.3 ±2.5
IBIAS Input Bias Current 0.02 ±1 pA
±50
IOS Input Offset Current 5 fA
CMRR Common Mode Rejection Ratio 0V ≤VCM ≤4V 81 97 dB
80
PSRR Power Supply Rejection Ratio 1.6V ≤V+≤5.5V 83 120 dB
V−= 0V, VCM = 0V 83
CMRR ≥80 dB −0.2 4.2
CMVR Common Mode Voltage Range V
CMRR ≥79 dB −0.2 4.2
VO= 0.3V to 4.7V 110
AVOL Large Signal Voltage Gain 120 dB
RL= 10 kΩto V+/2 108
VOOutput Swing High RL= 10 kΩto V+/2 17 50 mV
VIN(diff) = 100 mV 50 from either
rail
Output Swing Low RL= 10 kΩto V+/2 17 50
VIN(diff) = −100 mV 50
IOOutput Current (4) Sourcing, VOto V–27 30 mA
VIN(diff) = 100 mV 19
Sinking, VOto V+17 22
VIN(diff) = −100 mV 12
ISSupply Current 10 16 µA
18
(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 such that TJ= TA. No ensured specification of parametric performance is indicated in the electrical
tables under conditions of internal self-heating where TJ> TA. Absolute Maximum Ratings indicate junction temperature limits beyond
which the device may be permanently degraded, either mechanically or electrically.
(2) All limits are specified by testing, statistical analysis or design.
(3) Typical values represent the most likely parametric norm 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.
(4) The short circuit test is a momentary open loop test.
Copyright © 2008–2013, Texas Instruments Incorporated Submit Documentation Feedback 3
Product Folder Links: LMP2231
LMP2231
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
www.ti.com
5V AC Electrical Characteristics(1)
Unless otherwise specified, all limits ensured for TA= 25°C, V+= 5V, V−= 0V, VCM = VO= V+/2, and RL> 1 MΩ.Boldface
limits apply at the temperature extremes.
Symbol Parameter Conditions Min(2) Typ(3) Max(2) Units
GBW Gain-Bandwidth Product CL= 20 pF, RL= 10 kΩ130 kHz
SR Slew Rate AV= +1 Falling Edge 33 58
32 V/ms
Rising Edge 33 48
32
θmPhase Margin CL= 20 pF, RL= 10 kΩ78 deg
GmGain Margin CL= 20 pF, RL= 10 kΩ27 dB
enInput-Referred Voltage Noise Density f = 1 kHz 60 nV/√Hz
Input-Referred Voltage Noise 0.1 Hz to 10 Hz 2.3 μVPP
inInput-Referred Current Noise f = 1 kHz 10 fA/√Hz
THD+N Total Harmonic Distortion + Noise f = 100 Hz, RL= 10 kΩ0.002 %
(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 such that TJ= TA. No ensured specification of parametric performance is indicated in the electrical
tables under conditions of internal self-heating where TJ> TA. Absolute Maximum Ratings indicate junction temperature limits beyond
which the device may be permanently degraded, either mechanically or electrically.
(2) All limits are specified by testing, statistical analysis or design.
(3) Typical values represent the most likely parametric norm 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.
3.3V DC Electrical Characteristics(1)
Unless otherwise specified, all limits ensured for TA= 25°C, V+= 3.3V, V−= 0V, VCM = VO= V+/2, and RL> 1 MΩ.Boldface
limits apply at the temperature extremes.
Symbol Parameter Conditions Min(2) Typ(3) Max(2) Units
VOS Input Offset Voltage ±10 ±160 μV
±250
TCVOS Input Offset Voltage Drift LMP2231A ±0.3 ±0.4 μV/°C
LMP2231B ±0.3 ±2.5
IBIAS Input Bias Current 0.02 ±1 pA
±50
IOS Input Offset Current 5 fA
CMRR Common Mode Rejection Ratio 0V ≤VCM ≤2.3V 79 92 dB
77
PSRR Power Supply Rejection Ratio 1.6V ≤V+≤5.5V 83 120 dB
V−= 0V, VCM = 0V 83
CMRR ≥78 dB −0.2 2.5
CMVR Common Mode Voltage Range V
CMRR ≥77 dB −0.2 2.5
VO= 0.3V to 3V 108
AVOL Large Signal Voltage Gain 120 dB
RL= 10 kΩto V+/2 107
VOOutput Swing High RL= 10 kΩto V+/2 14 50 mV
VIN(diff) = 100 mV 50 from either
rail
Output Swing Low RL= 10 kΩto V+/2 50
14
VIN(diff) = −100 mV 50
(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 such that TJ= TA. No ensured specification of parametric performance is indicated in the electrical
tables under conditions of internal self-heating where TJ> TA. Absolute Maximum Ratings indicate junction temperature limits beyond
which the device may be permanently degraded, either mechanically or electrically.
(2) All limits are specified by testing, statistical analysis or design.
(3) Typical values represent the most likely parametric norm 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.
4Submit Documentation Feedback Copyright © 2008–2013, Texas Instruments Incorporated
Product Folder Links: LMP2231
LMP2231
www.ti.com
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
3.3V DC Electrical Characteristics(1) (continued)
Unless otherwise specified, all limits ensured for TA= 25°C, V+= 3.3V, V−= 0V, VCM = VO= V+/2, and RL> 1 MΩ.Boldface
limits apply at the temperature extremes.
Symbol Parameter Conditions Min(2) Typ(3) Max(2) Units
IOOutput Current (4) Sourcing, VOto V–11 14 mA
VIN(diff) = 100 mV 8
Sinking, VOto V+8 11
VIN(diff) = −100 mV 5
ISSupply Current 10 15 µA
16
(4) The short circuit test is a momentary open loop test.
3.3V AC Electrical Characteristics(1)
Unless otherwise is specified, all limits ensured for TA= 25°C, V+= 3.3V, V−= 0V, VCM = VO= V+/2, and RL> 1 MΩ.Boldface
limits apply at the temperature extremes.
Symbol Parameter Conditions Min(2) Typ(3) Max(2) Units
GBW Gain-Bandwidth Product CL= 20 pF, RL= 10 kΩ128 kHz
SR Slew Rate AV= +1, CL= 20 pF Falling Edge 58 V/ms
RL= 10 kΩRising Edge 48
θmPhase Margin CL= 20 pF, RL= 10 kΩ76 deg
GmGain Margin CL= 20 pF, RL= 10 kΩ26 dB
enInput-Referred Voltage Noise Density f = 1 kHz 60 nV/√Hz
Input-Referred Voltage Noise 0.1 Hz to 10 Hz 2.4 μVPP
inInput-Referred Current Noise f = 1 kHz 10 fA/√Hz
THD+N Total Harmonic Distortion + Noise f = 100 Hz, RL= 10 kΩ0.003 %
(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 such that TJ= TA. No ensured specification of parametric performance is indicated in the electrical
tables under conditions of internal self-heating where TJ> TA. Absolute Maximum Ratings indicate junction temperature limits beyond
which the device may be permanently degraded, either mechanically or electrically.
(2) All limits are specified by testing, statistical analysis or design.
(3) Typical values represent the most likely parametric norm 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.
2.5V DC Electrical Characteristics(1)
Unless otherwise specified, all limits ensured for TA= 25°C, V+= 2.5V, V−= 0V, VCM = VO= V+/2, and RL> 1MΩ.Boldface
limits apply at the temperature extremes.
Symbol Parameter Conditions Min(2) Typ(3) Max(2) Units
VOS Input Offset Voltage ±10 ±190 μV
±275
TCVOS Input Offset Voltage Drift LMP2231A ±0.3 ±0.4 μV/°C
LMP2231B ±0.3 ±2.5
IBIAS Input Bias Current 0.02 ±1.0 pA
±50
IOS Input Offset Current 5 fA
CMRR Common Mode Rejection Ratio 0V ≤VCM ≤1.5V 77 91 dB
76
(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 such that TJ= TA. No ensured specification of parametric performance is indicated in the electrical
tables under conditions of internal self-heating where TJ> TA. Absolute Maximum Ratings indicate junction temperature limits beyond
which the device may be permanently degraded, either mechanically or electrically.
(2) All limits are specified by testing, statistical analysis or design.
(3) Typical values represent the most likely parametric norm 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.
Copyright © 2008–2013, Texas Instruments Incorporated Submit Documentation Feedback 5
Product Folder Links: LMP2231
LMP2231
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
www.ti.com
2.5V DC Electrical Characteristics(1) (continued)
Unless otherwise specified, all limits ensured for TA= 25°C, V+= 2.5V, V−= 0V, VCM = VO= V+/2, and RL> 1MΩ.Boldface
limits apply at the temperature extremes.
Symbol Parameter Conditions Min(2) Typ(3) Max(2) Units
PSRR Power Supply Rejection Ratio 1.6V ≤V+≤5.5V 83 120 dB
V−= 0V, VCM = 0V 83
CMVR Common Mode Voltage Range CMRR ≥77 dB −0.2 1.7 V
CMRR ≥76 dB −0.2 1.7
AVOL Large Signal Voltage Gain VO= 0.3V to 2.2V 104 120 dB
RL= 10 kΩto V+/2 104
VOOutput Swing High RL= 10 kΩto V+/2 12 50 mV
VIN(diff) = 100 mV 50 from either
Output Swing Low RL= 10 kΩto V+/2 13 50 rail
VIN (diff) = −100 mV 50
IOOutput Current (4) Sourcing, VOto V−5 8
VIN(diff) = 100 mV 4mA
Sinking, VOto V+3.5 7
VIN(diff) = −100 mV 2.5
ISSupply Current 10 14 µA
15
(4) The short circuit test is a momentary open loop test.
2.5V AC Electrical Characteristics(1)
Unless otherwise specified, all limits ensured for TA= 25°C, V+= 2.5V, V−= 0V, VCM = VO= V+/2, and RL> 1MΩ.Boldface
limits apply at the temperature extremes.
Symbol Parameter Conditions Min(2) Typ(3) Max(2) Units
GBW Gain-Bandwidth Product CL= 20 pF, RL= 10 kΩ128 kHz
SR Slew Rate AV= +1, CL= 20 pF Falling Edge 58 V/ms
RL= 10 kΩRising Edge 48
θmPhase Margin CL= 20 pF, RL= 10 kΩ74 deg
GmGain Margin CL= 20 pF, RL= 10 kΩ26 dB
enInput-Referred Voltage Noise Density f = 1 kHz 60 nV/√Hz
Input-Referred Voltage Noise 0.1 Hz to 10 Hz 2.5 μVPP
inInput-Referred Current Noise f = 1 kHz 10 fA/√Hz
THD+N Total Harmonic Distortion + Noise f = 100 Hz, RL= 10 kΩ0.005 %
(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 such that TJ= TA. No ensured specification of parametric performance is indicated in the electrical
tables under conditions of internal self-heating where TJ> TA. Absolute Maximum Ratings indicate junction temperature limits beyond
which the device may be permanently degraded, either mechanically or electrically.
(2) All limits are specified by testing, statistical analysis or design.
(3) Typical values represent the most likely parametric norm 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.
6Submit Documentation Feedback Copyright © 2008–2013, Texas Instruments Incorporated
Product Folder Links: LMP2231
LMP2231
www.ti.com
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
1.8V DC Electrical Characteristics (1)
Unless otherwise specified, all limits ensured for TA= 25°C, V+= 1.8V, V−= 0V, VCM = VO= V+/2, and RL> 1 MΩ.Boldface
limits apply at the temperature extremes.
Symbol Parameter Conditions Min(2) Typ(3) Max(2) Units
VOS Input Offset Voltage ±10 ±230 μV
±325
TCVOS Input Offset Voltage Drift LMP2231A ±0.3 ±0.4 μV/°C
LMP2231B ±0.3 ±2.5
IBIAS Input Bias Current 0.02 ±1.0 pA
±50
IOS Input Offset Current 5 fA
CMRR Common Mode Rejection Ratio 0V ≤VCM ≤0.8V 76 92 dB
75
PSRR Power Supply Rejection Ratio 1.6V ≤V+≤5.5V 83 120 dB
V−= 0V, VCM = 0V 83
CMRR ≥76 dB −0.2 1.0
CMVR Common Mode Voltage Rang V
CMRR ≥75 dB 0 1.0
VO= 0.3V to 1.5V 103
AVOL Large Signal Voltage Gain 120 dB
RL= 10 kΩto V+/2 103
VOOutput Swing High RL= 10 kΩto V+/2 12 50 mV
VIN(diff) = 100 mV 50 from either
RL= 10 kΩto V+/2 50 rail
Output Swing Low 13
VIN(diff) = −100 mV 50
IOOutput Current (4) Sourcing, VOto V−2.5 5
VIN(diff) = 100 mV 2mA
Sinking, VOto V+2 5
VIN(diff) = −100 mV 1.5
ISSupply Current 10 14 µA
15
(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 such that TJ= TA. No ensured specification of parametric performance is indicated in the electrical
tables under conditions of internal self-heating where TJ> TA. Absolute Maximum Ratings indicate junction temperature limits beyond
which the device may be permanently degraded, either mechanically or electrically.
(2) All limits are specified by testing, statistical analysis or design.
(3) Typical values represent the most likely parametric norm 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.
(4) The short circuit test is a momentary open loop test.
1.8V AC Electrical Characteristics(1)
Unless otherwise is specified, all limits ensured for TA= 25°C, V+= 1.8V, V−= 0V, VCM = VO= V+/2, and RL> 1 MΩ.Boldface
limits apply at the temperature extremes.
Symbol Parameter Conditions Min(2) Typ(3) Max(2) Units
GBW Gain-Bandwidth Product CL= 20 pF, RL= 10 kΩ127 kHz
SR Slew Rate AV= +1, CL= 20 pF Falling Edge 58 V/ms
RL= 10 kΩRising Edge 48
θmPhase Margin CL= 20 pF, RL= 10 kΩ70 deg
GmGain Margin CL= 20 pF, RL= 10 kΩ25 dB
enInput-Referred Voltage Noise Density f = 1 kHz 60 nV/√Hz
Input-Referred Voltage Noise 0.1 Hz to 10 Hz 2.4 μVPP
(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 such that TJ= TA. No ensured specification of parametric performance is indicated in the electrical
tables under conditions of internal self-heating where TJ> TA. Absolute Maximum Ratings indicate junction temperature limits beyond
which the device may be permanently degraded, either mechanically or electrically.
(2) All limits are specified by testing, statistical analysis or design.
(3) Typical values represent the most likely parametric norm 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.
Copyright © 2008–2013, Texas Instruments Incorporated Submit Documentation Feedback 7
Product Folder Links: LMP2231
V+
1
2
3
4 5
6
7
8
N/C
VIN-
VIN+
V-
N/C
VOUT
N/C
-
+
OUT
V-
IN+
V+
IN-
+-
1
2
3
5
4
LMP2231
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
www.ti.com
1.8V AC Electrical Characteristics(1) (continued)
Unless otherwise is specified, all limits ensured for TA= 25°C, V+= 1.8V, V−= 0V, VCM = VO= V+/2, and RL> 1 MΩ.Boldface
limits apply at the temperature extremes.
Symbol Parameter Conditions Min(2) Typ(3) Max(2) Units
inInput-Referred Current Noise f = 1 kHz 10 fA/√Hz
THD+N Total Harmonic Distortion + Noise f = 100 Hz, RL= 10 kΩ0.005 %
Connection Diagram
Figure 2. 5-Pin SOT-23 (Top View) Figure 3. 8-Pin SOIC (Top View)
See Package Number DBV0005A See Package Number D0008A
8Submit Documentation Feedback Copyright © 2008–2013, Texas Instruments Incorporated
Product Folder Links: LMP2231
-150 -100 -50 050 100 150
VOS (PV)
0
2
4
6
8
10
12
14
PERCENTAGE (%)
VS = 2.5V
TA = 25°C
VCM = VS/2
-2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5
0
2
4
6
8
10
PERCENTAGE (%)
TCVOS (PV/°C)
VS = 2.5V
VCM = VS/2
-40°C dTA d125°C
-150 -100 -50 050 100 150
VOS (PV)
0
2
4
6
8
10
12
14
PERCENTAGE (%)
VS = 3.3V
TA = 25°C
VCM = VS/2
-2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5
0
2
4
6
8
10
PERCENTAGE (%)
TCVOS (PV/°C)
-40°C dTA d125°C
VS = 3.3V
VCM = VS/2
-150 -100 -50 050 100 150
VOS (PV)
0
2
4
6
8
10
12
14
16
PERCENTAGE (%)
VS = 5V
TA = 25°C
VCM = VS/2
-2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 2.5
0
2
4
6
8
10
PERCENTAGE (%)
TCVOS (PV/°C)
VS = 5V
VCM = VS/2
-40°C dTA d125°C
LMP2231
www.ti.com
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
Typical Performance Characteristics
Unless otherwise Specified: TA= 25°C, VS= 5V, VCM = VS/2, where VS= V+- V−
Offset Voltage Distribution TCVOS Distribution
Figure 4. Figure 5.
Offset Voltage Distribution TCVOS Distribution
Figure 6. Figure 7.
Offset Voltage Distribution TCVOS Distribution
Figure 8. Figure 9.
Copyright © 2008–2013, Texas Instruments Incorporated Submit Documentation Feedback 9
Product Folder Links: LMP2231
-0.2 0.2 0.6 1 1.4 1.8
-250
-150
-50
50
150
250
VOS (PV)
VCM (V)
VS = 2.5V
-40°C 25°C 85°C
125°C
2.2
-0.2 0 0.2 0.4 0.6 0.8 1 1.2 1.4
VCM (V)
-250
-150
-50
50
150
250
VOS (PV)
-40°C 25°C
85°C
125°C
VS = 1.8V
-0.2 0.2 0.6 1 1.4 1.8 2.2 2.6 3
-250
-150
-50
50
150
250
VOS (PV)
VCM (V)
-40°C 25°C
85°C
125°C
VS = 3.3V
-0.2 0.8 1.8 2.8 3.8
-250
-150
-50
50
250
OFFSET VOLTAGE (PV)
VCM (V)
150
4.3
85°C
25°C
125°C
-40°C VS = 5V
-150 -100 -50 0 50 100 150
VOS (PV)
0
2
4
6
8
10
12
PERCENTAGE (%)
VS = 1.8V
TA = 25°C
VCM = VS/2
LMP2231
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
www.ti.com
Typical Performance Characteristics (continued)
Unless otherwise Specified: TA= 25°C, VS= 5V, VCM = VS/2, where VS= V+- V−
Offset Voltage Distribution TCVOS Distribution
Figure 10. Figure 11.
Offset Voltage vs. Offset Voltage vs.
VCM VCM
Figure 12. Figure 13.
Offset Voltage vs. Offset Voltage vs.
VCM VCM
Figure 14. Figure 15.
10 Submit Documentation Feedback Copyright © 2008–2013, Texas Instruments Incorporated
Product Folder Links: LMP2231
1.5 2 2.5 3 3.5 4 4.5 5 5.5
SUPPLY VOLTAGE (V)
-40
-20
0
20
40
60
80
100
OFFSET VOLTAGE (PV)
VCM = 0V
-40°C
25°C
85°C
125°C
-40 -20 020 40 60 80 100 120
TEMPERATURE (°C)
-80
-60
-20
0
120
100
80
40
OFFSET VOLTAGE (PV)
-40
20
60
VS = 1.8V, 2.5V, 3.3V, 5V
5 TYPICAL PARTS
LMP2231
www.ti.com
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
Typical Performance Characteristics (continued)
Unless otherwise Specified: TA= 25°C, VS= 5V, VCM = VS/2, where VS= V+- V−
Offset Voltage vs. Offset Voltage vs.
Temperature Supply Voltage
Figure 16. Figure 17.
Time Domain Voltage Noise Time Domain Voltage Noise
Figure 18. Figure 19.
Time Domain Voltage Noise Time Domain Voltage Noise
Figure 20. Figure 21.
Copyright © 2008–2013, Texas Instruments Incorporated Submit Documentation Feedback 11
Product Folder Links: LMP2231
0
-100
-75
-25
0
25
50
75
100
INPUT BIAS CURRENT (fA)
VCM (V)
-50
0.5 1 1.5 2 2.5
VS = 3.3V
-40°C
25°C
0
-20
-15
-5
0
5
10
15
20
INPUT BIAS CURRENT (pA)
VCM (V)
-10
0.5 1 1.5 2 2.5
VS = 3.3V
85°C
125°C
0 0.5 1 1.5 2
-40
-30
-20
-10
0
10
20
30
40
INPUT BIAS CURRENT (fA)
VCM (V)
25°C
-40°C
VS = 2.5V
0 0.25 0.5 0.75 1 1.25 1.5
-10
-8
-6
-4
-2
0
2
4
6
8
10
INPUT BIAS CURRENT (pA)
VCM (V)
VS = 2V
85°C
125°C
LMP2231
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
www.ti.com
Typical Performance Characteristics (continued)
Unless otherwise Specified: TA= 25°C, VS= 5V, VCM = VS/2, where VS= V+- V−
Input Bias Current vs. Input Bias Current vs.
VCM VCM
Figure 22. Figure 23.
Input Bias Current vs. Input Bias Current vs.
VCM VCM
Figure 24. Figure 25.
Input Bias Current vs. Input Bias Current vs.
VCM VCM
Figure 26. Figure 27.
12 Submit Documentation Feedback Copyright © 2008–2013, Texas Instruments Incorporated
Product Folder Links: LMP2231
10 100 1k 10k 100k
FREQUENCY (Hz)
-160
-140
-120
-100
-80
-60
-40
-20
0
PSRR (dB)
+PSRR
-PSRR
VS = 2V, 2.5V, 3.3V, 5V
VS = 2V
VS = 5V
1.5 2.5 3.5 4.5 5.5
SUPPLY VOLTAGE (V)
5
6
7
8
9
10
11
SUPPLY CURRENT (PA)
125°C
85°C
25°C
-40°C
0 1 2 3 4
VCM (V)
-30
-20
-10
0
10
20
30
-25
-15
-5
5
15
25
INPUT BIAS CURRENT (pA)
VS = 5V
125°C
85°C
0123 4
VCM (V)
-300
-200
-100
0
100
200
300
400
500
600
INPUT BIAS CURRENT (fA)
25°C
-40°C
VS = 5V
LMP2231
www.ti.com
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
Typical Performance Characteristics (continued)
Unless otherwise Specified: TA= 25°C, VS= 5V, VCM = VS/2, where VS= V+- V−
Input Bias Current vs. Input Bias Current vs.
VCM VCM
Figure 28. Figure 29.
PSRR vs. Supply Current vs.
Frequency Supply Voltage
Figure 30. Figure 31.
Copyright © 2008–2013, Texas Instruments Incorporated Submit Documentation Feedback 13
Product Folder Links: LMP2231
10 1k 1M
FREQUENCY (Hz)
-25
25
100
GAIN (dB)
100k
10k
100
75
50
0VS = 1.8V, 2.5V, 3.3V, 5V
RL = 10 k:, 100 k:, 10 M:
CL = 20 pF, 50 pF, 100 pF
GAIN
PHASE
-30
30
120
90
60
0
PHASE (°)
10 1k 1M
FREQUENCY (Hz)
-25
25
100
GAIN (dB)
100k
10k
100
75
50
0
PHASE
GAIN
-30
30
120
90
60
0
PHASE (°)
VS = 5V
RL = 10 k:
CL = 20 pF
-40°C 25°C
85°C
125°C
-40°C
25°C
125°C
85°C
1.5 2.5 3.5 4.5 5.5
SUPPLY VOLTAGE (V)
10
15
20
25
VOUT FROM RAIL (mV)
125°C
85°C
25°C
-40°C
RL = 10 k:
1.5 2.5 3.5 4.5 5.5
SUPPLY VOLTAGE (V)
5
10
15
20
25
30
VOUT FROM RAIL (mV)
125°C
85°C
-40°C
25°C
RL = 10 k:
1.5 2.5 3.5 4.5 5.5
SUPPLY VOLTAGE (V)
0
5
10
15
20
25
30
35
40
ISOURCE (mA)
-40°C
25°C
85°C
125°C
1.5 2.5 3.5 4.5 5.5
SUPPLY VOLTAGE (V)
0
5
10
15
20
25
30
ISINK (mA)
125°C
85°C
25°C
-40°C
LMP2231
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
www.ti.com
Typical Performance Characteristics (continued)
Unless otherwise Specified: TA= 25°C, VS= 5V, VCM = VS/2, where VS= V+- V−
Sinking Current vs. Sourcing Current vs.
Supply Voltage Supply Voltage
Figure 32. Figure 33.
Output Swing High vs. Output Swing Low vs.
Supply Voltage Supply Voltage
Figure 34. Figure 35.
Open Loop Frequency Response Open Loop Frequency Response
Figure 36. Figure 37.
14 Submit Documentation Feedback Copyright © 2008–2013, Texas Instruments Incorporated
Product Folder Links: LMP2231
500 mV/DIV
100 Ps/DIV
VS = 5V
VIN = 2 VPP
f = 1 kHz
AV = +1
RL = 10 k:
CL = 20 pF
50 mV/DIV
100 Ps/DIV
VS = 5V
VIN = 200 mVPP
f = 1 kHz
AV = +1
RL = 10 k:
CL = 20 pF
0.01 0.1 1 10
VOUT (VPP)
0.001
0.01
0.1
1
10
THD+N (%)
RL = 10 k:
CL = 20 pF
VS = 2.5V
VS = 2V
VS = 3.3V VS = 5V
f = 1 kHz
1 10 100 100k
FREQUENCY (Hz)
0.001
0.1
1
THD+N (%)
10k1k
0.0001
0.01 VS = 2.5V
VS = 2V
VS = 3.3V VS = 5V
RL = 10 k:
CL = 20 pF
VO = VS ± 1V
1.5 2 2.5 3 3.5 4 4.5 5 5.5
SUPPLY VOLTAGE (V)
40
44
48
52
56
60
SLEW RATE (V/ms)
FALLING EDGE
RISING EDGE
20 40 60 80 100
CAPACITIVE LOAD (pF)
50
60
70
80
90
PHASE MARGIN (°)
VS = 5V
RL = 100 k:
RL = 10 k:
VS = 2.5V
VS = 3.3V
VS = 1.8V
LMP2231
www.ti.com
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
Typical Performance Characteristics (continued)
Unless otherwise Specified: TA= 25°C, VS= 5V, VCM = VS/2, where VS= V+- V−
Phase Margin vs. Slew Rate vs.
Capacitive Load Supply Voltage
Figure 38. Figure 39.
THD+N vs. THD+N vs.
Amplitude Frequency
Figure 40. Figure 41.
Large Signal Step Response Small Signal Step Response
Figure 42. Figure 43.
Copyright © 2008–2013, Texas Instruments Incorporated Submit Documentation Feedback 15
Product Folder Links: LMP2231
10 100 1k 10k 100k
FREQUENCY (Hz)
0
20
40
60
80
100
120
140
CMRR (dB)
VS = 2.5V
VS = 3.3V
VS = 5V
110 100 1k 10k
FREQUENCY (Hz)
1
10
100
1000
VOLTAGE NOISE nV/
Hz)
VS = 5V
1V/DIV
100 Ps/DIV
VS = 5V
VIN = 400 mVPP
f = 1 kHz
AV = +10
RL = 10 k:
CL = 20 pF
100 mV/DIV
100 Ps/DIV
VS = 5V
VIN = 50 mVPP
f = 1 kHz
AV = +10
RL = 10 k:
CL = 20 pF
LMP2231
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
www.ti.com
Typical Performance Characteristics (continued)
Unless otherwise Specified: TA= 25°C, VS= 5V, VCM = VS/2, where VS= V+- V−
Large Signal Step Response Small Signal Step Response
Figure 44. Figure 45.
CMRR Input Voltage Noise
vs. vs.
Frequency Frequency
Figure 46. Figure 47.
16 Submit Documentation Feedback Copyright © 2008–2013, Texas Instruments Incorporated
Product Folder Links: LMP2231
eni = en +
2ei +
2et
2
LMP2231
www.ti.com
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
APPLICATION INFORMATION
LMP2231
The LMP2231 is a single CMOS precision amplifier that offer low offset voltage and low offset voltage drift, and
high gain while only consuming 10 μA of current per channel.
The LMP2231 is a micropower op amp, consuming only 10 μA of current. Micropower op amps extend the run
time of battery powered systems and reduce energy consumption in energy limited systems. The ensured supply
voltage range of 1.8V to 5.0V along with the ultra-low supply current extend the battery run time in two ways. The
extended ensured power supply voltage range of 1.8V to 5.0V enables the op amp to function when the battery
voltage has depleted from its nominal value down to 1.8V. In addition, the lower power consumption increases
the life of the battery.
The LMP2231 has an input referred offset voltage of only ±150 μV maximum at room temperature. This offset is
ensured to be less than ±230 μV over temperature. This minimal offset voltage along with very low TCVOS of only
0.3 µV/°C typical allows more accurate signal detection and amplification in precision applications.
The low input bias current of only ±20 fA gives the LMP2231 superiority for use in high impedance sensor
applications. Bias Current of an amplifier flows through source resistance of the sensor and the voltage resulting
from this current flow appears as a noise voltage on the input of the amplifier. The low input bias current enables
the LMP2231 to interface with high impedance sensors while generating negligible voltage noise. Thus the
LMP2231 provides better signal fidelity and a higher signal-to-noise ration when interfacing with high impedance
sensors.
Texas Instruments is heavily committed to precision amplifiers and the market segment they serve. Technical
support and extensive characterization data is available for sensitive applications or applications with a
constrained error budget.
The operating supply voltage range of 1.8V to 5.5V over the extensive temperature range of −40°C to 125°C
makes the LMP2231 an excellent choice for low voltage precision applications with extensive temperature
requirements.
The LMP2231 is offered in the space saving 5-Pin SOT-23 and 8-pin SOIC package. These small packages are
ideal solutions for area constrained PC boards and portable electronics.
TOTAL NOISE CONTRIBUTION
The LMP2231 has a very low input bias current, very low input current noise, and low input voltage noise for
micropower amplifier. As a result, this amplifier makes a great choice for circuits with high impedance sensor
applications.
Figure 48 shows the typical input noise of the LMP2231 as a function of source resistance where:
endenotes the input referred voltage noise
eiis the voltage drop across source resistance due to input referred current noise or ei= RS* in
etshows the thermal noise of the source resistance
eni shows the total noise on the input.
Where:
The input current noise of the LMP2231 is so low that it will not become the dominant factor in the total noise
unless source resistance exceeds 300 MΩ, which is an unrealistically high value. As is evident in Figure 48, at
lower RSvalues, total noise is dominated by the amplifier’s input voltage noise. Once RSis larger than a 100 kΩ,
then the dominant noise factor becomes the thermal noise of RS. As mentioned before, the current noise will not
be the dominant noise factor for any practical application.
Copyright © 2008–2013, Texas Instruments Incorporated Submit Documentation Feedback 17
Product Folder Links: LMP2231
REDUCED INPUT VOLTAGE NOISE = en1+en2+
2 2 +enN
2
=
1
N
1
NNen
2=N
Nen
=1en
N
10 1k 100k 10M
RS (:)
0.1
1
100
1000
1M
10k
100
10
eni
en
ei
VOLTAGE NOISE DENSITY (nV/
Hz)
et
LMP2231
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
www.ti.com
Figure 48. Total Input Noise
VOLTAGE NOISE REDUCTION
The LMP2231 has an input voltage noise of 60 nV/√Hz . While this value is very low for micropower amplifiers,
this input voltage noise can be further reduced by placing N amplifiers in parallel as shown in Figure 49. The total
voltage noise on the output of this circuit is divided by the square root of the number of amplifiers used in this
parallel combination. This is because each individual amplifier acts as an independent noise source, and the
average noise of independent sources is the quadrature sum of the independent sources divided by the number
of sources. For N identical amplifiers, this means:
Figure 49 shows a schematic of this input voltage noise reduction circuit. Typical resistor values are: RG= 10Ω,
RF=1kΩ, and RO=1kΩ.
18 Submit Documentation Feedback Copyright © 2008–2013, Texas Instruments Incorporated
Product Folder Links: LMP2231
+
-
+
-
-
+
R2KR2
R1
R1
R2KR2
VOUT
V1
V2
V01
V02
R1
a
R11 =
V-
V+
VOUT
RO
RG
VIN
RF
V-
V+
RO
RG
RF
V-
V+
RO
RG
RF
V-
V+
RO
RG
RF
+
-
+
-
+
-
+
-
LMP2231
www.ti.com
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
Figure 49. Noise Reduction Circuit
PRECISION INSTRUMENTATION AMPLIFIER
Measurement of very small signals with an amplifier requires close attention to the input impedance of the
amplifier, gain of the overall signal on the inputs, and the gain on each input of the amplifier. This is because the
difference of the input signal on the two inputs is of the interest and the common signal is considered noise. A
classic circuit implementation is an instrumentation amplifier. Instrumentation amplifiers have a finite, accurate,
and stable gain. They also have extremely high input impedances and very low output impedances. Finally they
have an extremely high CMRR so that the amplifier can only respond to the differential signal. A typical
instrumentation amplifier is shown in Figure 50.
Figure 50. Instrumentation Amplifier
There are two stages in this amplifier. The last stage, output stage, is a differential amplifier. In an ideal case the
two amplifiers of the first stage, input stage, would be set up as buffers to isolate the inputs. However they
cannot be connected as followers because of mismatch of amplifiers. That is why there is a balancing resistor
between the two. The product of the two stages of gain will give the gain of the instrumentation amplifier. Ideally,
the CMRR should be infinite. However the output stage has a small non-zero common mode gain which results
from resistor mismatch.
Copyright © 2008–2013, Texas Instruments Incorporated Submit Documentation Feedback 19
Product Folder Links: LMP2231
VO = -K (2a + 1) (V1 - V2)
VO = KR2
R2(VO2 - VO1)
= -K (VO1 - VO2)
R11 = V1 - V2
V
VO1 - VO2 = (2R1 + ) I
R11 R11
= (2a + 1) V R11
= (2a + 1) R11 xIR11
GIVEN: I R1= IR11
LMP2231
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
www.ti.com
In the input stage of the circuit, current is the same across all resistors. This is due to the high input impedance
and low input bias current of the LMP2231.
(1)
By Ohm’s Law:
(2)
However:
(3)
So we have:
VO1–VO2 = (2a+1)(V1–V2) (4)
Now looking at the output of the instrumentation amplifier:
(5)
Substituting from Equation 4:
(6)
This shows the gain of the instrumentation amplifier to be:
−K(2a+1) (7)
Typical values for this circuit can be obtained by setting: a = 12 and K= 4. This results in an overall gain of −100.
SINGLE SUPPLY STRAIN GAGE BRIDGE AMPLIFIER
Strain gauges are popular electrical elements used to measure force or pressure. Strain gauges are subjected to
an unknown force which is measured as a the deflection on a previously calibrated scale. Pressure is often
measured using the same technique; however this pressure needs to be converted into force using an
appropriate transducer. Strain gauges are often resistors which are sensitive to pressure or to flexing. Sense
resistor values range from tens of ohms to several hundred kilo ohms. The resistance change which is a result of
applied force across the strain gauge might be 1% of its total value. An accurate and reliable system is needed
to measure this small resistance change. Bridge configurations offer a reliable method for this measurement.
Bridge sensors are formed of four resistors, connected as a quadrilateral. A voltage source or a current source is
used across one of the diagonals to excite the bridge while a voltage detector across the other diagonal
measures the output voltage.
Bridges are mainly used as null circuits or to measure a differential voltages. Bridges will have no output voltage
if the ratios of two adjacent resistor values are equal. This fact is used in null circuit measurements. These are
particularly used in feedback systems which involve electrochemical elements or human interfaces. Null systems
force an active resistor, such as a strain gauge, to balance the bridge by influencing the measured parameter.
Often in sensor applications at lease one of the resistors is a variable resistor, or a sensor. The deviation of this
active element from its initial value is measured as an indication of change in the measured quantity. A change in
output voltage represents the sensor value change. Since the sensor value change is often very small, the
resulting output voltage is very small in magnitude as well. This requires an extensive and very precise
amplification circuitry so that signal fidelity does not change after amplification.
Sensitivity of a bridge is the ratio of its maximum expected output change to the excitation voltage change.
20 Submit Documentation Feedback Copyright © 2008–2013, Texas Instruments Incorporated
Product Folder Links: LMP2231
ADC121S021
IN
V+
LM4140A
6
2
1,4,7,8
3
V+
1 PF
+
-
0.1 PF
10 PF
VA
V+
+
-
+
-
-
+
12 k:
10 k:40 k:
½
LMP2232
R+'R
R+'R
R
R
V+
V+
V+
12 k:
10 k:40 k:
1 k:LMP2231
½
LMP2232
LMP2231
GND
EXCITATION
SOURCE
R1R2
R3R4
VOUT
(a)
VOUT
1 + R3
R1
¨
¨
©
§
¨
¨
©
§
1 + R4
R2
¨
¨
©
§
¨
¨
©
§
R3
R1-R4
R2 x VSOURCE
=
EXCITATION
SOURCE
R + 'RR - 'R
R - 'R R + 'R
VOUT
(b)
VOUT ='R
Rx VSOURCE
LMP2231
www.ti.com
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
Figure 51 (a) shows a typical bridge sensor and Figure 51(b) shows the bridge with four sensors. R in
Figure 51(b) is the nominal value of the sense resistor and the deviations from R are proportional to the quantity
being measured.
Figure 51. Bridge Sensor
Instrumentation amplifiers are great for interfacing with bridge sensors. Bridge sensors often sense a very small
differential signal in the presence of a larger common mode voltage. Instrumentation amplifiers reject this
common mode signal.
Figure 52 shows a strain gauge bridge amplifier. In this application the LMP2231 is used to buffer the LM4140's
precision output voltage. The LM4140A is a precision voltage reference. The other three LMP2231s are used to
form an instrumentation amplifier. This instrumentation amplifier uses the LMP2231's high CMRR and low VOS
and TCVOS to accurately amplify the small differential signal generated by the output of the bridge sensor. This
amplified signal is then fed into the ADC121S021 which is a 12-bit analog to digital converter. This circuit works
on a single supply voltage of 5V.
Figure 52. Strain Gauge Bridge Amplifier
Copyright © 2008–2013, Texas Instruments Incorporated Submit Documentation Feedback 21
Product Folder Links: LMP2231
-
+VOUT
V
-
V+
99 k:
1 k:
1 k:
RL
OXYGEN SENSOR
LMP2231
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
www.ti.com
PORTABLE GAS DETECTION SENSOR
Gas sensors are used in many different industrial and medical applications. They generate a current which is
proportional to the percentage of a particular gas sensed in an air sample. This current goes through a load
resistor and the resulting voltage drop is measured. Depending on the sensed gas and sensitivity of the sensor,
the output current can be in the order of tens of microamperes to a few milliamperes. Gas sensor datasheets
often specify a recommended load resistor value or they suggest a range of load resistors to choose from.
Oxygen sensors are used when air quality or oxygen delivered to a patient needs to be monitored. Fresh air
contains 20.9% oxygen. Air samples containing less than 18% oxygen are considered dangerous. Oxygen
sensors are also used in industrial applications where the environment must lack oxygen. An example is when
food is vacuum packed. There are two main categories of oxygen sensors, those which sense oxygen when it is
abundantly present (i.e. in air or near an oxygen tank) and those which detect traces of oxygen in ppm.
Figure 53 shows a typical circuit used to amplify the output of an oxygen detector. The LMP2231 makes an
excellent choice for this application as it only draws 10 µA of current and operates on supply voltages down to
1.8V. This application detects oxygen in air. The oxygen sensor outputs a known current through the load
resistor. This value changes with the amount of oxygen present in the air sample. Oxygen sensors usually
recommend a particular load resistor value or specify a range of acceptable values for the load resistor. Oxygen
sensors typically have a life of one to two years. The use of the micropower LMP2231 means minimal power
usage by the op amp and it enhances the battery life. Depending on other components present in the circuit
design, the battery could last for the entire life of the oxygen sensor. The precision specifications of the
LMP2231, such as its very low offset voltage, low TCVOS , low input bias current, low CMRR, and low PSRR are
other factors which make the LMP2231 a great choice for this application.
Figure 53. Precision Oxygen Sensor
22 Submit Documentation Feedback Copyright © 2008–2013, Texas Instruments Incorporated
Product Folder Links: LMP2231
LMP2231
www.ti.com
SNOSB01E –JANUARY 2008–REVISED MARCH 2013
REVISION HISTORY
Changes from Revision D (March 2013) to Revision E Page
• Changed layout of National Data Sheet to TI format .......................................................................................................... 22
Copyright © 2008–2013, Texas Instruments Incorporated Submit Documentation Feedback 23
Product Folder Links: LMP2231
PACKAGE OPTION ADDENDUM
www.ti.com 23-Aug-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
LMP2231AMA/NOPB ACTIVE SOIC D 8 95 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LMP22
31AMA
LMP2231AMAE/NOPB ACTIVE SOIC D 8 250 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LMP22
31AMA
LMP2231AMAX/NOPB ACTIVE SOIC D 8 2500 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LMP22
31AMA
LMP2231AMF/NOPB ACTIVE SOT-23 DBV 5 1000 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 AL5A
LMP2231AMFE/NOPB ACTIVE SOT-23 DBV 5 250 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 AL5A
LMP2231AMFX/NOPB ACTIVE SOT-23 DBV 5 3000 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 AL5A
LMP2231BMA/NOPB ACTIVE SOIC D 8 95 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LMP22
31BMA
LMP2231BMAE/NOPB ACTIVE SOIC D 8 250 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 LMP22
31BMA
LMP2231BMF/NOPB ACTIVE SOT-23 DBV 5 1000 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 AL5B
LMP2231BMFE/NOPB ACTIVE SOT-23 DBV 5 250 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 AL5B
LMP2231BMFX/NOPB ACTIVE SOT-23 DBV 5 3000 Green (RoHS
& no Sb/Br) CU SN Level-1-260C-UNLIM -40 to 125 AL5B
(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 <=1000ppm threshold. Antimony trioxide based
flame retardants must also meet the <=1000ppm threshold requirement.
PACKAGE OPTION ADDENDUM
www.ti.com 23-Aug-2017
Addendum-Page 2
(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.
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
LMP2231AMAE/NOPB SOIC D 8 250 178.0 12.4 6.5 5.4 2.0 8.0 12.0 Q1
LMP2231AMAX/NOPB SOIC D 8 2500 330.0 12.4 6.5 5.4 2.0 8.0 12.0 Q1
LMP2231AMF/NOPB SOT-23 DBV 5 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3
LMP2231AMFE/NOPB SOT-23 DBV 5 250 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3
LMP2231AMFX/NOPB SOT-23 DBV 5 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3
LMP2231BMAE/NOPB SOIC D 8 250 178.0 12.4 6.5 5.4 2.0 8.0 12.0 Q1
LMP2231BMF/NOPB SOT-23 DBV 5 1000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3
LMP2231BMFE/NOPB SOT-23 DBV 5 250 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3
LMP2231BMFX/NOPB SOT-23 DBV 5 3000 178.0 8.4 3.2 3.2 1.4 4.0 8.0 Q3
PACKAGE MATERIALS INFORMATION
www.ti.com 24-Aug-2017
Pack Materials-Page 1
*All dimensions are nominal
Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm)
LMP2231AMAE/NOPB SOIC D 8 250 210.0 185.0 35.0
LMP2231AMAX/NOPB SOIC D 8 2500 367.0 367.0 35.0
LMP2231AMF/NOPB SOT-23 DBV 5 1000 210.0 185.0 35.0
LMP2231AMFE/NOPB SOT-23 DBV 5 250 210.0 185.0 35.0
LMP2231AMFX/NOPB SOT-23 DBV 5 3000 210.0 185.0 35.0
LMP2231BMAE/NOPB SOIC D 8 250 210.0 185.0 35.0
LMP2231BMF/NOPB SOT-23 DBV 5 1000 210.0 185.0 35.0
LMP2231BMFE/NOPB SOT-23 DBV 5 250 210.0 185.0 35.0
LMP2231BMFX/NOPB SOT-23 DBV 5 3000 210.0 185.0 35.0
PACKAGE MATERIALS INFORMATION
www.ti.com 24-Aug-2017
Pack Materials-Page 2
www.ti.com
PACKAGE OUTLINE
C
TYP
0.22
0.08
0.25
3.0
2.6
2X 0.95
1.9
1.45 MAX
TYP
0.15
0.00
5X 0.5
0.3
TYP
0.6
0.3
TYP
8
0
1.9
A
3.05
2.75
B
1.75
1.45
(1.1)
SOT-23 - 1.45 mm max heightDBV0005A
SMALL OUTLINE TRANSISTOR
4214839/C 04/2017
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. Refernce JEDEC MO-178.
0.2 C A B
1
34
5
2
INDEX AREA
PIN 1
GAGE PLANE
SEATING PLANE
0.1 C
SCALE 4.000
www.ti.com
EXAMPLE BOARD LAYOUT
0.07 MAX
ARROUND 0.07 MIN
ARROUND
5X (1.1)
5X (0.6)
(2.6)
(1.9)
2X (0.95)
(R0.05) TYP
4214839/C 04/2017
SOT-23 - 1.45 mm max heightDBV0005A
SMALL OUTLINE TRANSISTOR
NOTES: (continued)
4. Publication IPC-7351 may have alternate designs.
5. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
SYMM
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE:15X
PKG
1
34
5
2
SOLDER MASK
OPENING
METAL UNDER
SOLDER MASK
SOLDER MASK
DEFINED
EXPOSED METAL
METAL
SOLDER MASK
OPENING
NON SOLDER MASK
DEFINED
(PREFERRED)
SOLDER MASK DETAILS
EXPOSED METAL
www.ti.com
EXAMPLE STENCIL DESIGN
(2.6)
(1.9)
2X(0.95)
5X (1.1)
5X (0.6)
(R0.05) TYP
SOT-23 - 1.45 mm max heightDBV0005A
SMALL OUTLINE TRANSISTOR
4214839/C 04/2017
NOTES: (continued)
6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
7. Board assembly site may have different recommendations for stencil design.
SOLDER PASTE EXAMPLE
BASED ON 0.125 mm THICK STENCIL
SCALE:15X
SYMM
PKG
1
34
5
2
www.ti.com
PACKAGE OUTLINE
C
TYP
0.22
0.08
0.25
3.0
2.6
2X 0.95
1.9
1.45 MAX
TYP
0.15
0.00
5X 0.5
0.3
TYP
0.6
0.3
TYP
8
0
1.9
A
3.05
2.75
B
1.75
1.45
(1.1)
SOT-23 - 1.45 mm max heightDBV0005A
SMALL OUTLINE TRANSISTOR
4214839/C 04/2017
NOTES:
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing
per ASME Y14.5M.
2. This drawing is subject to change without notice.
3. Refernce JEDEC MO-178.
0.2 C A B
1
34
5
2
INDEX AREA
PIN 1
GAGE PLANE
SEATING PLANE
0.1 C
SCALE 4.000
www.ti.com
EXAMPLE BOARD LAYOUT
0.07 MAX
ARROUND 0.07 MIN
ARROUND
5X (1.1)
5X (0.6)
(2.6)
(1.9)
2X (0.95)
(R0.05) TYP
4214839/C 04/2017
SOT-23 - 1.45 mm max heightDBV0005A
SMALL OUTLINE TRANSISTOR
NOTES: (continued)
4. Publication IPC-7351 may have alternate designs.
5. Solder mask tolerances between and around signal pads can vary based on board fabrication site.
SYMM
LAND PATTERN EXAMPLE
EXPOSED METAL SHOWN
SCALE:15X
PKG
1
34
5
2
SOLDER MASK
OPENING
METAL UNDER
SOLDER MASK
SOLDER MASK
DEFINED
EXPOSED METAL
METAL
SOLDER MASK
OPENING
NON SOLDER MASK
DEFINED
(PREFERRED)
SOLDER MASK DETAILS
EXPOSED METAL
www.ti.com
EXAMPLE STENCIL DESIGN
(2.6)
(1.9)
2X(0.95)
5X (1.1)
5X (0.6)
(R0.05) TYP
SOT-23 - 1.45 mm max heightDBV0005A
SMALL OUTLINE TRANSISTOR
4214839/C 04/2017
NOTES: (continued)
6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate
design recommendations.
7. Board assembly site may have different recommendations for stencil design.
SOLDER PASTE EXAMPLE
BASED ON 0.125 mm THICK STENCIL
SCALE:15X
SYMM
PKG
1
34
5
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 © 2018, Texas Instruments Incorporated
Mouser Electronics
Authorized Distributor
Click to View Pricing, Inventory, Delivery & Lifecycle Information:
Texas Instruments:
LMP2231AMA/NOPB LMP2231AMAE/NOPB LMP2231AMAX/NOPB LMP2231AMF/NOPB LMP2231AMFE/NOPB
LMP2231AMFX/NOPB LMP2231BMA/NOPB LMP2231BMAE/NOPB LMP2231BMAX/NOPB LMP2231BMF/NOPB
LMP2231BMFE/NOPB LMP2231BMFX/NOPB