LMP7312MAX/NOPB [TI]

Single, 5.5-V, 1-MHz operational amplifier | D | 14 | -40 to 125;
LMP7312MAX/NOPB
型号: LMP7312MAX/NOPB
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

Single, 5.5-V, 1-MHz operational amplifier | D | 14 | -40 to 125

放大器 光电二极管
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LMP7312  
www.ti.com  
SNOSB32B MARCH 2010REVISED MARCH 2013  
LMP7312 Precision SPI-Programmable AFE with Differential/Single-Ended Input/Output  
Check for Samples: LMP7312  
1
FEATURES  
DESCRIPTION  
Typical Values, TA = 25°C, V+=5V, V-=0V.  
The LMP7312 is a digitally programmable variable  
gain amplifier/attenuator. Its wide input voltage range  
and superior precision make it a prime choice for  
applications requiring high accuracy such as data  
acquisition systems for IO modules in programmable  
2
Gain Bandwidth 1 MHz  
Input Voltage Range (G= 0.096 V/V) -15V to  
+15V  
logic control (PLC). The LMP7312 provides  
a
Core Op-Amp Input Offset Voltage 100 µV  
(Max)  
differential output to maximize dynamic range and  
signal to noise ratio, thereby reducing the overall  
system error. It can also be configured to handle  
single ended input data converters by means of the  
VOCM pin (see Application Section for details). The  
inputs of LMP7312 can be configured in attenuation  
mode to handle large input signals of up to +/- 15V,  
as well as in amplification mode to handle current  
loops of 0-20mA and 4-20mA.The LMP7312 is  
equipped with a null switch to evaluate the offset of  
the internal amplifier. A ensured 0.035% maximum  
gain error (for all gains) and a maximum gain drift of  
5ppm over the extended industrial temperature range  
(-40° to 125°C) make the LMP7312 very attractive for  
high precision systems even under harsh conditions.  
A low input offset voltage of 100µV and low voltage  
Supply Current 2 mA (Max)  
Gain (Attenuation Mode) 0.096 V/V, 0.192  
V/V0.384 V/V, 0.768 V/V  
Gain (Amplification Mode) 1 V/V, 2 V/V  
Gain Error 0.035% (Max)  
Core Op-Amp PSRR 90 dB (Min)  
CMRR 80 dB (min)  
Adjustable Output Common Mode 1V to 4V  
Temperature Range 40 to 125°C  
Package 14-Pin SOIC  
APPLICATIONS  
noise of 3µVpp give the LMP7312  
a superior  
Signal Conditioning AFE  
±10V; ±5V; 0-5V; 0-10V; 0-20mA; 4-20mA  
performance. The LMP7312 is fully specified from -  
40° to 125°C and is available in SOIC-14 package.  
Data Acquisition Systems  
Motor Control  
Instrument and Process Control  
Remote Sensing  
Programmable Automation Control  
1
Please 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.  
2
All trademarks are the property of their respective owners.  
PRODUCTION DATA information is current as of publication date.  
Products conform to specifications per the terms of the Texas  
Instruments standard warranty. Production processing does not  
necessarily include testing of all parameters.  
Copyright © 2010–2013, Texas Instruments Incorporated  
LMP7312  
SNOSB32B MARCH 2010REVISED MARCH 2013  
www.ti.com  
Typical Application  
+
V
V
IO  
SCK  
CS  
SPI  
Controller  
SDI  
SDO  
R
R
1
Sensor  
N
-V  
IN  
R
F
2
+
P
N
V
REF  
+V  
-V  
V
ADC  
-IN  
OUT  
-
+
-
Driver  
R
S
ADC  
+IN  
+
I
4-20 mA  
S
/V  
OUT  
R
R
V
2
CM  
P
P
+V  
IN  
+
V
R
1
R
F
N
100 kW  
100 kW  
V
OCM  
-
V
-
V
-
+
LMP™ is a trademark of Texas Instruments Corporation.  
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LMP7312  
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SNOSB32B MARCH 2010REVISED MARCH 2013  
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.  
(1)(2)  
Absolute Maximum Ratings  
ESD Rating  
(3)  
Human Body Model  
2000V  
Machine Body Model  
150V  
Charge device Model  
1000V  
Analog Supply Voltage (VS = V+ - V-)  
DigitaI Supply Voltage (VDIO=VIO-V-)  
Attenuation pins -VIN, +VIN referred to V-  
Amplification pins -IN, +IN referred to V-  
Voltage at all other pins referred to V-  
Storage Temperature Range  
6V  
6V  
±17.5V  
±10V  
6V  
-65°C to 150°C  
For soldering specification: http://www.ti.com/lit/SNOA549  
Junction Temperature  
150°C  
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for  
which the device is intended to be functional, but for which specific performance is not ensured. For ensured specifications and the test  
conditions, see Electrical Characteristics.  
(2) If Military/Aerospace specified devices are required, please contact the Texas Instruments 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).  
(1)  
Operating Ratings  
Analog Supply Voltage (VS = V+ – V-), V-=0V  
Digital Supply Voltage (VDIO = VIO– V-), V-=0V  
Attenuation pins -VIN, +VIN referred to V-  
Amplification pins -IN, +IN referred to V-  
4.5V to 5.5V  
2.7V to 5.5V  
-15V to 15V  
-2.35V to 7.35V  
40°C to 125°C  
(2)  
Temperature Range  
(2)  
Package Thermal Resistance  
SOIC-14  
145°C/W  
(1) Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for  
which the device is intended to be functional, but for which specific performance is not ensured. For ensured specifications and the test  
conditions, see 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(max) = (TJ(max) – TA)/ θJA. All numbers apply for packages soldered directly onto a PC Board.  
(1)  
5V Electrical Characteristics  
Unless otherwise specified, all limits ensured for TA = 25°C, V+ = 5V, VIO = 5V, V= 0V, G = 0.192 V/V, VCM_ATT=(+VIN+(-  
VIN))/2, VCM_AMP=(+IN+(-IN))/2. Differential output configuration. SE = Single Ended Output, DE = Differential Output.Boldface  
limits apply at the temperature extremes.  
(2)  
(3)  
(2)  
Symbol  
Parameter  
Conditions  
Min  
Typ  
Max  
Units  
VOS  
Core op-amp Input  
Offset Voltage  
Nulling Switch Mode, DE, VOCM = 1V;  
Nulling switch Mode, SE, -VOUT/VR = 1V  
–100  
–250  
100  
250  
µV  
Nulling Switch Mode, DE, VOCM = 4V;  
Nulling Switch Mode, SE, -VOUT/VR = 4V  
–100  
–250  
100  
250  
(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.  
(2) All limits are specified by testing, design, or statistical analysis.  
(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 © 2010–2013, Texas Instruments Incorporated  
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SNOSB32B MARCH 2010REVISED MARCH 2013  
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5V Electrical Characteristics (1) (continued)  
Unless otherwise specified, all limits ensured for TA = 25°C, V+ = 5V, VIO = 5V, V= 0V, G = 0.192 V/V, VCM_ATT=(+VIN+(-  
VIN))/2, VCM_AMP=(+IN+(-IN))/2. Differential output configuration. SE = Single Ended Output, DE = Differential Output.Boldface  
limits apply at the temperature extremes.  
(2)  
(3)  
(2)  
Symbol  
Parameter  
Conditions  
Min  
-3  
Typ  
±1.5  
Max  
Units  
TCVOS  
Core op-amp Input  
Nulling Switch Mode, DE, VOCM = 1V;  
Nulling Switch Mode, SE, -VOUT/VR = 1V  
3
(4)  
Offset Voltage  
µV/°C  
Nulling Switch Mode, DE, VOCM = 4V;  
Nulling Switch Mode, SE, -VOUT/VR = 4V  
-3  
±1.5  
3
All gains, RL = 10 k, CL = 50pF, SE / DE  
–0.035  
–0.045  
0.035  
0.045  
Gain Error  
Gain Drift  
%
Av  
en  
SE / DE  
-5  
±1  
5
ppm/°C  
nV/Hz  
Core op-amp Voltage  
Noise Density  
RTI, Nulling Switch Mode, f = 10 kHz  
7.25  
Core op-amp Peak to  
Peak Voltage Noise  
RTI, Nulling Switch Mode, f= 0.1Hz to 10Hz  
3
µVPP  
IVA  
Analog Supply Current +VIN = VIN = VOCM  
2
mA  
μA  
kΩ  
IVIO  
Digital Supply Current  
CM Input Resistance  
Without any load connected to SDO pin  
120  
RIN_CM  
G= 0.192 V/V  
62.08  
40  
G= 1 V/V  
RIN_DIFF  
Differential Input  
Resistance  
G= 0.192 V/V  
248.3  
160  
kΩ  
G= 1 V/V  
G= 0.096V/V, -15V < VCM_ATT < 15V, SE / DE  
G= 0.192V/V, -11.4V < VCM_ATT < 15V, SE / DE  
G= 0.384V/V, -6V < VCM_ATT < 11V, SE / DE  
G= 0.768V/V, -3V < VCM_ATT < 8V, SE / DE  
G= 1V/V, -2.3V < VCM_AMP < 7.3V, SE / DE  
G= 2V/V, -1.15V < VCM_AMP < 6.15V, SE / DE.  
Nulling Switch Mode, 4.5V <V+ <5.5V  
DC Common Mode  
Rejection Ratio  
80  
77  
CMRR  
PSRR  
dB  
dB  
Core op-amp DC  
90  
Power Supply Rejection  
Ratio  
(5)  
VOCM_OS VOCM Output Offset  
VOCM = 2.5 V  
-20  
20  
V+0.2  
mV  
V
VOUT  
Positive Output Voltage RL = 10 k, CL = 50 pF,  
Swing  
+VIN= 15V, -VIN= -15V  
Negative Output  
Voltage Swing  
RL = 10 k, CL = 50 pF,  
+VIN= -15V, -VIN= 15V  
V+0.2  
10  
+VIN= -VIN = 2.5V, +VOUT, -VOUT/VR connected  
individually to either V+ or V-  
Short circuit current  
Current limitation  
IOUT  
mA  
Internal current limiter  
55  
Attenuation Mode, G = 0.096 V/V, RL =10 k,  
CL = 50 pF  
1.2  
1.0  
MHz  
Attenuation Mode, G = 0.192 V/V, RL = 10 k,  
CL = 50 pF  
Attenuation Mode, G = 0.384 V/V, RL = 10 k,  
CL = 50 pF  
560  
310  
530  
280  
GBW  
Bandwidth  
kHz  
kHz  
Attenuation Mode, G = 0.768 V/V, RL = 10 k,  
CL = 50 pF  
Amplification Mode, G = 1 V/V, RL = 10 k,  
CL = 50 pF  
Amplification Mode, G = 2 V/V, RL = 10 k,  
CL = 50 pF  
(4) Offset voltage temperature drift is determined by dividing the change in VOS at the temperature extremes by the total temperature  
change.  
(5) VOCM_OS is the difference between the Output Common mode voltage (+VOUT+(-VOUT/VR))/2 and the Voltage on the VOCM pin.  
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SNOSB32B MARCH 2010REVISED MARCH 2013  
5V Electrical Characteristics (1) (continued)  
Unless otherwise specified, all limits ensured for TA = 25°C, V+ = 5V, VIO = 5V, V= 0V, G = 0.192 V/V, VCM_ATT=(+VIN+(-  
VIN))/2, VCM_AMP=(+IN+(-IN))/2. Differential output configuration. SE = Single Ended Output, DE = Differential Output.Boldface  
limits apply at the temperature extremes.  
(2)  
(3)  
(2)  
Symbol  
Parameter  
Slew Rate  
Conditions  
Min  
Typ  
1.4  
Max  
Units  
SR  
RL = 10 k, CL = 50 pF  
V/μsec  
(6)  
THD+N  
Total Harmonic  
Distorsion + Noise  
Vout = 4.096 Vpp, f = 1KHz,  
RL = 10 kΩ  
0.0026  
%
(6) The number specified is the average of rising and falling slew rates and is measured at 90% to 10%.  
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(1)  
Electrical Characteristics (Serial Interface)  
Unless otherwise specified. All limits ensured for TA = 25°C, V+ = 5V, V= 0V, 2.7V < VIO < 5.5V  
(2)  
(3)  
(2)  
Symbol  
VIL  
Parameter  
Conditions  
Min  
Typ  
Max  
0.8  
Units  
Input Logic Low Threshold  
V
V
VIH  
Input Logic High Threshold (SDO pin)  
Output logic Low Threshold (SDO pin)  
2
VOL  
ISDO= 100µA  
ISDO= 2mA  
0.2  
0.4  
V
V
VOH  
Output logic High Threshold  
ISDO= 100µA  
VIO-0.2  
VIO-0.6  
100  
ISDO= 2mA  
(4)  
t1  
t2  
t3  
t4  
t5  
t6  
t7  
High Period, SCK  
ns  
ns  
ns  
ns  
ns  
ns  
(4)  
(4)  
(4)  
(4)  
(4)  
(4)  
Low Period, SCK  
100  
Set Up Time, CS to SCK  
Set Up Time, SDI to SCK  
Hold Time, SCK to SDI  
Prop. Delay, SCK to SDO  
50  
30  
10  
60  
Hold Time, SCK Transition to CS Rising  
Edge  
50  
ns  
ns  
ns  
ns  
(4)  
(4)  
t8  
t9  
CS Inactive  
100  
10  
Hold Time, SCK Transition to CS Falling  
Edge  
(4)  
tR/tF  
Signal Rise and Fall Times  
1.5  
5
(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.  
(2) All limits are specified by testing, design, or statistical analysis.  
(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) Load for these tests is shown in Test Circuit Diagram.  
TEST CIRCUIT DIAGRAM  
I
OL  
100 mA  
V
IO  
/2  
TO SDO PIN  
C
L
20 pF  
I
OH  
100 mA  
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Timing Diagram  
SCK  
t
9
t
t
t
2
1
7
t
3
CS  
SDI  
t
8
t
t
5
4
DNœ4  
DN  
DNœ1  
t
6
SDO  
OLD DN  
OLD DNœ3  
OLD DNœ4  
Connection Diagram  
1
14  
13  
12  
11  
SDI  
+IN  
SCK  
-
2
3
4
5
6
V
-IN  
V
OCM  
+V  
-V  
/V  
OUT  
IN  
IN  
R
LMP7312  
-V  
+V  
10  
9
OUT  
+
CS  
V
SDO  
8
7
V
IO  
Figure 1. 14-Pin SOIC-Top View  
PIN DESCRIPTIONS  
Pin  
1
Name  
SDI  
Description  
SPI data IN  
2
+IN  
Non-inverting input of Amplification pair  
Inverting input of Amplification pair  
Non-inverting input of Attenuation pair  
Inverting input of Attenuation pair  
SPI chip select  
3
-IN  
4
+VIN  
-VIN  
5
6
CS  
7
SDO  
VIO  
SPI data OUT  
8
SPI supply voltage  
9
V+  
Positive supply voltage  
10  
11  
12  
13  
14  
+VOUT  
-VOUT/VR  
VOCM  
V−  
Non-inverting output  
Inverting output in differential output mode, reference input in single-ended operation mode  
Output common mode voltage in DE  
Negative supply voltage, reference for both Analog and Digital supplies  
SPI Clock  
SCK  
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Typical Performance Characteristics  
Unless otherwise specified, TA = 25°C, V+ = 5V, VIO = 5V, V= 0V, VCM_ATT=(+VIN+(-VIN))/2, VCM_AMP=(+IN+(-IN))/2. RL =  
10k, CL =50pF, Differential output configuration.  
Offset Voltage distribution (PMOS)  
Offset Voltage distribution (NMOS)  
Figure 2.  
Figure 3.  
TCVOS distribution (PMOS)  
TCVOS distribution (NMOS)  
15  
12  
9
Nulling Switch Mode  
V
OCM  
= 1V  
6
3
0
-2.0 -1.5 -1.0 -0.5 0.0 0.5 1.0 1.5 2.0  
TCV  
(éV/°C)  
OS  
Figure 4.  
Figure 5.  
Noise  
vs.  
Frequency (Core op-amp)  
0.1Hz to 10Hz Noise (Core op-amp)  
100  
10  
1
1s/DIV  
10  
100  
1k  
10k  
100k  
1M  
FREQUENCY (Hz)  
Figure 6.  
Figure 7.  
8
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Typical Performance Characteristics (continued)  
Unless otherwise specified, TA = 25°C, V+ = 5V, VIO = 5V, V= 0V, VCM_ATT=(+VIN+(-VIN))/2, VCM_AMP=(+IN+(-IN))/2. RL =  
10k, CL =50pF, Differential output configuration.  
Gain  
Gain  
vs.  
vs.  
Frequency (Attenuation Mode)  
Frequency (Amplification Mode)  
9
6
3
0
-5  
Gain 2V/V  
-10  
-15  
-20  
-25  
Gain 1V/V  
0
-3  
-6  
100  
1k  
10k  
100k  
1M  
100  
1k  
10k  
100k  
1M  
10M  
FREQUENCY (Hz)  
FREQUENCY (Hz)  
Figure 8.  
Figure 9.  
CMRR  
vs.  
CMRR  
vs.  
Frequency (Attenuation Mode)  
Frequency (Amplification Mode)  
100  
90  
100  
90  
80  
70  
60  
50  
80  
70  
60  
V
= 4V  
100k  
OCM  
V
= 4V  
OCM  
50  
10  
100  
1k  
10k  
1M  
10  
100  
1k  
10k  
100k  
1M  
FREQUENCY (Hz)  
FREQUENCY (Hz)  
Figure 10.  
Figure 11.  
Vos  
vs.  
PSRR (Core op-amp)  
Input Common Mode Voltage  
110  
100  
90  
15  
10  
5
NULLING SWITCH MODE  
0
80  
-5  
-10  
-15  
-20  
-25  
70  
60  
50  
10  
100  
1k  
10k  
100k  
1M  
1.0  
1.0  
2.0  
2.5  
3.0  
3.5  
4.0  
V
(V)  
FREQUENCY (Hz)  
OCM  
Figure 12.  
Figure 13.  
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Typical Performance Characteristics (continued)  
Unless otherwise specified, TA = 25°C, V+ = 5V, VIO = 5V, V= 0V, VCM_ATT=(+VIN+(-VIN))/2, VCM_AMP=(+IN+(-IN))/2. RL =  
10k, CL =50pF, Differential output configuration.  
Small signal step (Attenuation Mode)  
Small signal step (Amplification Mode)  
= 2.5V  
V
= 2.5V  
CM_ATT  
V
CM_AMP  
Gain 0.768V/V  
Gain 0.384V/V  
Input  
Input  
Gain 2V/V  
Gain 0.192V/V  
Gain 1V/V  
Gain 0.096V/V  
5 ms/DIV  
Figure 15.  
5 ms/DIV  
Figure 14.  
Large signal step (Attenuation Mode)  
Large signal step (Amplification Mode)  
= 2.5V  
V
= 2.5V  
CM_ATT  
V
CM_AMP  
Input  
Gain 0.768V/V  
Gain 0.384V/V  
Input  
Gain 2V/V  
Gain 1V/V  
Gain 0.192V/V  
Gain 0.096V/V  
5 ms/DIV  
5 ms/DIV  
Figure 16.  
Figure 17.  
Settling time – Rise (Attenuation Mode)  
= 2.5V  
Settling time – Rise (Amplification Mode)  
V
V
= 2.5V  
CM_ATT  
CM_AMP  
Input  
Gain 0.384V/V  
Gain 2V/V  
Input  
Gain 0.096V/V  
Gain 0.192V/V  
Gain 1V/V  
Gain 0.768V/V  
500 ns/DIV  
500 ns/DIV  
Figure 18.  
Figure 19.  
10  
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Typical Performance Characteristics (continued)  
Unless otherwise specified, TA = 25°C, V+ = 5V, VIO = 5V, V= 0V, VCM_ATT=(+VIN+(-VIN))/2, VCM_AMP=(+IN+(-IN))/2. RL =  
10k, CL =50pF, Differential output configuration.  
Settling time – Fall (Attenuation Mode)  
Settling time – Fall (Amplification Mode)  
V
= 2.5V  
CM_AMP  
Input  
V
= 2.5V  
Input  
CM_ATT  
Gain 2V/V  
Gain 0.768V/V  
Gain 0.384V/V  
Gain 0.096V/V  
Gain 1V/V  
Gain 0.192V/V  
500 ns/DIV  
500 ns/DIV  
Figure 20.  
Figure 21.  
Gain change (Attenuation Mode)  
Gain change (Amplification Mode)  
CS  
Gain 0.096V/V  
CS  
Gain 1V/V  
Gain 0.768V/V  
10 ms/DIV  
Gain 2V/V  
10 ms/DIV  
Figure 23.  
Figure 22.  
THD + N (Attenuation Mode)  
THD + N (Amplification Mode)  
1
0.1  
Differential Input  
Differential Input  
1
0.1  
V
= 2.5V  
CM_ATT  
V
= 2.5V  
CM_AMP  
+V  
-(-V  
) = 4.096 Vpp  
OUT  
OUT  
+V  
OUT  
-(-V  
) = 4.096 Vpp  
OUT  
Gain 0.192V/V  
Gain 2V/V  
0.01  
0.001  
0.01  
Gain 1V/V  
100  
Gain 0.096V/V  
10k 100k  
0.001  
10  
1k  
10k  
100k  
10  
100  
1k  
FREQUENCY (Hz)  
FREQUENCY (Hz)  
Figure 24.  
Figure 25.  
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Typical Performance Characteristics (continued)  
Unless otherwise specified, TA = 25°C, V+ = 5V, VIO = 5V, V= 0V, VCM_ATT=(+VIN+(-VIN))/2, VCM_AMP=(+IN+(-IN))/2. RL =  
10k, CL =50pF, Differential output configuration.  
IVA  
vs.  
VA  
IVIO  
vs.  
VIO Voltage  
1.35  
1.31  
1.27  
1.23  
1.19  
1.15  
75  
67  
59  
51  
43  
35  
125°C  
25°C  
4.5  
4.7  
4.9  
5.1  
(V)  
5.3  
5.5  
2.7  
3.3  
3.8  
4.4  
(V)  
4.9  
5.5  
V
V
A
IO  
Figure 26.  
Figure 27.  
Short Circuit Current +VOUT  
Short Circuit Current -VOUT  
vs.  
vs.  
Temperature  
Temperature  
50.0  
30.0  
50.0  
30.0  
10.0  
10.0  
-10.0  
-30.0  
-50.0  
-10.0  
-30.0  
-50.0  
-40  
-7  
26  
59  
92  
125  
-40  
-7  
26  
59  
92  
125  
TEMPERATURE (°C)  
TEMPERATURE (°C)  
Figure 28.  
Figure 29.  
Output voltage swing +VOUT  
Output voltage swing -VOUT  
vs.  
vs.  
Output current  
Output current  
5.0  
4.0  
3.0  
2.0  
1.0  
0
5.0  
4.0  
3.0  
2.0  
1.0  
0
-40°C  
-40°C  
SINK  
SINK  
VIN+ = +15V  
VIN- = -15V  
VIN+ = -15V  
VIN- = +15V  
25°C  
25°C  
125°C  
125°C  
125°C  
125°C  
25°C  
25°C  
SOURCE  
VIN+ = +15V  
VIN- = -15V  
SOURCE  
VIN+ = -15V  
VIN- = +15V  
-40°C  
-20  
-40°C  
-20  
-30  
-10  
0
10  
20  
30  
-30  
-10  
0
10  
20  
30  
OUTPUT CURRENT (mA)  
OUTPUT CURRENT (mA)  
Figure 30.  
Figure 31.  
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Typical Performance Characteristics (continued)  
Unless otherwise specified, TA = 25°C, V+ = 5V, VIO = 5V, V= 0V, VCM_ATT=(+VIN+(-VIN))/2, VCM_AMP=(+IN+(-IN))/2. RL =  
10k, CL =50pF, Differential output configuration.  
SDO sink current  
SDO source current  
vs.  
vs.  
SDO Voltage  
SDO Voltage  
20.0  
20.0  
16.0  
16.0  
12.0  
12.0  
8.0  
8.0  
4.0  
4.0  
0
0
1.0  
2.0  
3.0  
4.0  
(V)  
5.0  
6.0  
0
0.3  
0.6  
0.9  
(V)  
1.2  
1.5  
V
SDO  
V
SDO  
Figure 32.  
Figure 33.  
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APPLICATION SECTION  
GENERAL DESCRIPTION  
The LMP7312 is a single supply programmable gain difference amplifier with two input pairs: Attenuation pair (-  
VIN, +VIN) and Amplification pair (-IN, +IN). The output can be configured in both single-ended and differential  
modes with the output common mode voltage set by the user. The input selection, the gains and the mode of  
operation of the LMP7312 are controlled through a 4- wire SPI interface (SCK, CS, SDI, SDO). These features  
combined make the LMP7312 a very easy interface between the analog high voltage industrial buses and the  
low voltage digital converters.  
OUTPUT MODE CONFIGURATION  
The LMP7312 is able to work in both single ended and differential output mode. The selection of the mode is  
made through the VOCM (output common mode voltage) pin.  
Differential Output  
This mode of operation is enabled when the output common mode voltage pin (VOCM) is connected to a voltage  
higher than 1V, for instance the common mode voltage supplied by an ADC, (Figure 34) or a voltage reference. If  
the VOCM pin is floating an internal voltage divider biases it at the half supply voltage. In this configuration the  
output signals are set on the VOCM voltage level.  
Single-Ended Output  
This mode of operation is enabled when the VOCM pin is tied to a voltage less than 0.5 V, for example to ground.  
In this mode of operation the LMP7312 behaves as a difference amplifier, where the +VOUT pin is the single-  
ended output while the –VOUT /VR is the reference voltage.  
1. In the case of bipolar input signal the non inverting output will be connected to an external reference through  
a buffer (Figure 35).  
2. In the case of unipolar input signal the non inverting output will be connected to ground (Figure 36).  
In both cases the inverting output pin is configured as an input pin.  
+
V
V
IO  
SCK  
CS  
SPI  
Controller  
SDI  
SDO  
R
R
1
N
-V  
IN  
R
F
2
+
P
V
N
REF  
V
ADC  
+V  
-V  
OUT  
-IN  
+IN  
-
ADC  
+
/V  
OUT  
R
R
R
V
2
CM  
P
+
+V  
IN  
V
R
1
F
P
N
100 kW  
100 kW  
V
OCM  
-
V
-
V
-
+
Figure 34. Differential ADC Interfacing with VCM provided by the ADC  
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+
V
V
IO  
SCK  
CS  
SPI  
Controller  
SDI  
SDO  
R
1
N
-V  
IN  
R
2
R
F
P
+
N
V
ADC  
VREF  
+V  
OUT  
-IN  
+IN  
-
V
V
AC  
ADC  
+
-VOUT/V  
R
R
R
2
P
+
V
DC  
+V  
IN  
+
-
R
1
F
P
N
100 kW  
100 kW  
-
V
OCM  
+
-
V
-
VAC >0 , VAC <0  
Where VAC = -VIN œ (+VIN)  
V
Figure 35. Bipolar Input Signal to Single-Ended ADC Interface  
+
V
V
IO  
SCK  
CS  
SPI  
Controller  
SDI  
SDO  
R
R
1
N
-V  
IN  
R
2
F
+
N
P
V
ADC  
+V  
-V  
OUT  
-IN  
+IN  
-
V
AC  
ADC  
+
/V  
OUT  
R
R
R
2
P
+
V
V
DC  
+V  
IN  
+
-
R
1
F
P
N
100 kW  
V
OCM  
100 kW  
-
V
VAC > 0  
Where VAC = -VIN œ (+VIN)  
-
V
Figure 36. Unipolar Input Signal to Single-Ended ADC Interface  
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INPUT VOLTAGE RANGE  
The LMP7312 has an internal OpAmp with rail-to-rail input voltage range capability. The requirement to stay  
within the V-and V+ rail at the OpAmp input translates in an Input Voltage Range specification as explained in this  
application section.  
Differential Output  
Considering a single positive supply (V-= GND, V+ = VS) the Input Common mode voltage, VCM_ATT = (+VIN + (-  
VIN))/2 for the Attenuation inputs and VCM_AMP = (+IIN + (-IIN))/2 for the Amplification inputs, has to stay between  
the MIN and MAX values determined by these formulas:  
CMMAX = VS + 1/KV*(VS - VOCM  
)
CMMIN = -1/KV*VOCM  
KV is a function of the Gain according to the table below:  
Gain  
0.096 V/V  
0.192 V/V  
0.384 V/V  
0.768 V/V  
1 V/V  
2 V/V  
KV  
0.12  
0.218  
0.414  
0.806  
1.065  
2.096  
Regardless to the values derived by the formula, the voltage on each input pin must never exceed the specified  
Absolute Maximum Ratings.  
Below are some typical values:  
Table 1. Differential Input, Differential Output, VS= 5V, VOCM = 2.5V  
VCM_ATT  
VCM_AMP  
Gain  
Min  
-15 V(1)  
-11.5 V  
-6 V  
Max  
+15 V(1)  
+15 V  
Min  
Max  
0.096 V/V  
0.192 V/V  
0.384 V/V  
0.768 V/V  
1 V/V  
+11 V  
-3.1 V  
+8.1 V  
-2.3 V  
-1.2 V  
+7.3 V  
+6.2 V  
2 V/V  
(1) Limited by the operating ratings on input pins  
In the case of a single ended input referred to ground (-VIN = GND, -IN = GND) the table below summarizes the  
voltage range allowed on the +VIN and +IIN inputs.  
Table 2. Single Ended Input, Differential Output, VS= 5V, VOCM = 2.5V, -VIN = GND, -IIN = GND  
+VIN  
+IN  
Gain  
Min  
Max  
Min  
Max  
0.096 V/V  
0.192 V/V  
0.384 V/V  
0.768 V/V  
1 V/V  
-15 V(1)  
-15 V(1)  
-12 V(2)  
-6 V(2)  
+15 V(1)  
+15 V(1)  
+12 V(2)  
+6 V(2)  
-4.6 V(2)  
-2.3 V(2)  
+4.6 V(2)  
+2.3 V(2)  
2 V/V  
(1) Limited by the operating ratings on input pins.  
(2) Limited by the output voltage swing (0.2V to VS-0.2V on both + VOUT and -VOUT  
)
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Single Ended Output  
In this mode the LMP7312 behaves as a Difference Amplifier, with -VOUT/VR being the reference output voltage  
when a zero volt differential input signal is applied. The voltages at the OpAmp inputs are determined by +VIN  
and -VOUT/VR voltages. The voltage range of +VIN and +IIN inputs is as follows:  
VMAX = VS + 1/ KV * (VS – (-VOUT/VR))  
VMIN = -1/KV * (-VOUT/VR)  
Regardless of the values derived by the formula, the voltage on each input pin must never exceed the specified  
Absolute Maximum Ratings.  
Below are some typical values:  
Table 3. Differential Input, Single Ended Output, VS = 5V, VOCM = GND, and -VOUT/VR = 2.5V  
+VIN  
+IIN  
Gain  
Min  
-15 V(1)  
-11.5 V(1)  
-6 V  
Max  
+15 V(1)  
+15 V  
Min  
Max  
0.096 V/V  
0.192 V/V  
0.384 V/V  
0.768 V/V  
1 V/V  
+11 V  
-3.1 V  
+8.1 V  
-2.3 V  
-1.2 V  
+7.3 V  
+6.2 V  
2 V/V  
(1) Limited by the operating ratings on input pins  
In the case of a single ended input referred to ground (-VIN = GND, -IN = GND) this table summarize the voltage  
ranges allowed on the +VIN and +IIN inputs.  
Table 4. Single Ended Input, Single Ended Output, VS = 5V, VOCM = GND, -VOUT/VR = 2.5V, -VIN = GND, -IIN  
GND  
=
+VIN  
+IIN  
Gain  
Min  
Max  
Min  
Max  
0.096 V/V  
0.192 V/V  
0.384 V/V  
0.768 V/V  
1 V/V  
-15 V(1)  
-11.5 V  
-6 V(2)  
-3 V**  
+15 V(1)  
+12 V(2)  
+6 V(2)  
+3 V(2)  
-2.3 V(2)  
-1.1 V(2)  
+2.3 V(2)  
+1.1 V(2)  
2 V/V  
(1) Limited by the operating ratings on input pins.  
(2) Limited by the output voltage swing (0.2V to VS-0.2V on +VOUT  
)
SERIAL INTERFACE CONTROL OPERATION  
The serial interface control of the LMP7312 can be supplied with a voltage between 2.7V and 5.5V through the  
VIO pin for compatibility with different logic families present in the market.  
The LMP7312 Attenuation, Amplification, Null switch and HiZ modes are controlled by a register. Data to be  
written into the control register is first loaded into the LMP7312 via the serial interface. The serial interface  
employs a 5-bit shift register. Data is loaded through the serial data input, SDI. Data passing through the shift  
register is obtained through the serial data output, SDO. The serial clock, SCK controls the serial loading  
process. All five data bits are required to correctly program the device. The falling edge of CS enables the shift  
register to receive data. The SCK signal must be high during the falling edge of CS. Each data bit is clocked into  
the shift register on the rising edge of SCK. Data is transferred from the shift register to the holding register on  
the rising edge of CS. Operation is shown in the Timing Diagram.  
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SPI Registers  
MSB  
LSB  
Gain_1  
Gain_0  
EN_CL  
Null_SW  
Hi_Z  
Gain_0, Gain_1 bit:Gain Values  
Different gains are available in Attenuation Mode or Amplification Mode according to the following Gain Table.  
Gain_1  
Gain_0  
EN_CL  
Gain Value (V/V)  
0
0
1
1
1
1
0
1
0
1
0
1
0
0
0
0
1
1
0.096  
0.192  
0.384  
0.768  
1
2
EN_CL bit:Enable Amplification Mode  
This register selects which input pair is processed.  
EN_CL  
Mode  
Description  
0
1
Attenuation Mode  
Amplification Mode  
±VIN inputs are processed through the 104.16k input resistors  
±IN inputs are processed through the 40k input resistors  
NULL_SW bit: Input Offset Nulling Switch Mode  
This register selects a mode in which the amplifier is not processing any input but it is configured in unity gain to  
allow system level amplifier offset calibration. The Nulling Switch mode is available in both single ended and fully  
differential output mode. The LMP7312 in Nulling Switch and fully differential mode has he following  
configuration.  
NULL_SW  
Mode  
Description  
0
Normal Operation Mode  
±VIN and ±IN inputs are processed depending on EN_CL register  
setting.  
1
Nulling Switch Mode  
Enables to evaluate the offset of the internal amplifier for system  
level calibration  
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V
+
IO  
V
R
R
1
N
-V  
IN  
R
F
2
N
P
-IN  
+IN  
+V  
-
OUT  
-V  
OUT  
/V  
+
R
R
R
2
1
P
P
+
+V  
IN  
V
R
F
N
100 kW  
100 kW  
V
OCM  
-
V
-
V
Figure 37. LMP7312 in Nulling Switch Mode  
In this condition at the Output pins is possible to measure the input voltage offset of the op-amp:  
Output Mode  
Differential  
+VOUT  
VCM_out+VOS/2  
VR+VOS  
VOUT/VR  
VCM_out -VOS/2  
VR  
Single-Ended  
Hi_Z bit:High Impedance  
In this mode both outputs +VOUT and -VOUT/VR of the LMP7312 are in tri-state Figure 38.  
HI_Z  
Mode  
Description  
0
Normal Operation Mode  
The LMP7312 is configured according to value of the other 4 bits of the  
register.  
1
High Impedance Mode  
The LMP7312 output is in high impedance  
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+
V
IO  
V
R
R
1
N
-V  
IN  
R
F
2
P
N
-IN  
+IN  
+V  
-V  
-
OUT  
/V  
+
OUT  
R
R
R
2
1
P
P
+
+V  
IN  
V
R
F
N
100 kW  
100 kW  
V
OCM  
-
V
-
V
Figure 38. LMP7312 in High Impedance Mode  
In each case the SPI registers require 5 bits. The table below is a summary of all allowed configurations.  
MSB  
LSB  
Gain_1  
Gain_0  
EN_CL  
Null_SW  
Hi_Z  
Gain Value (V/V)  
Mode of Operation  
Attenuation Mode  
Attenuation Mode  
Attenuation Mode  
Attenuation Mode  
Amplification Mode  
Amplification Mode  
High Impedance Output  
Null Switch Mode  
0
0
1
1
1
1
x
x
0
1
0
1
0
1
x
x
0
0
0
0
1
1
x
x
0
0
0
0
0
0
x
1
0
0
0
0
0
0
1
0
0.096  
0.192  
0.384  
0.768  
1
2
1
Daisy Chain  
The LMP7312 supports daisy chaining of the serial data stream between multiple chips. To use this feature serial  
data is clocked into the first chip SDI pin, and the next chip SDI pin is connected to the SDO pin of the first chip.  
Both chips may share a chip select signal, or the second chip can be enabled separately. When the chip select  
pin goes low on both chips and 5 bits have been clocked into the first chip the next 5 clock cycle begins moving  
new configuration data into the second chip. With a full 10 clock cycles both chips have valid data and the chip  
select pin of both chips should be brought high to prevent the data from overshooting.  
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CS  
CS  
CS  
éController  
LMP7312  
SDO  
LMP7312  
MOSI  
SDI  
SDI  
SDO  
SCK  
SCK  
SCK  
MISO  
Figure 39. Daisy Chain  
Shared 4-wire SPI with ADC  
The LMP7312 is a good choice when interfacing to differential analog to digital converters ADC141S626 and  
ADC161S626 of PowerWise® Family. Its SPI interface has been designed to enable sharing CSB with the ADC.  
LMP7312 register access happens only when CSB is asserted low while SCK is high. However, the ADC starts  
conversion under any of the following conditions:  
1. CSB goes low while SCK is high  
2. CSB goes low while SCK is low  
3. CSB and SCK both going low  
Therefore, if a system uses timing condition #2 above, LMP7312 and ADC1x1S626 can share CSB and SCK as  
shown in Figure 40. The only side-effect would be that writing to LMP7312 triggers an ADC conversion, but then  
the result can be ignored. At other times, the LMP7312 is not affected by the CSB assertions used to initiate  
normal ADC conversions.  
CS  
CS  
CS  
éController  
LMP7312  
ADC1x1S626  
MOSI  
SDI  
SDO  
SCK  
SCK  
SCK  
MISO  
Figure 40. 4-wire SPI with ADC interface  
LMP7312 IN 4-20mA CURRENT LOOP APPLICATION  
The 4-20mA current loop shown in Figure 41 is a common method of transmitting sensor information in many  
industrial process-monitoring applications. Transmitting sensor information via a current loop is particularly useful  
when the information has to be sent to a remote location over long distances (1000 feet, or more). The loop’s  
operation is straightforward: a sensor’s output voltage is first converted to a proportional current, with 4mA  
normally representing the sensor’s zero-level output, and 20mA representing the sensor’s full-scale output. Then,  
a receiver at the remote end converts the 4-20mA current back into a voltage which in turn can be further  
processed by a computer or display module. A typical 4-20mA current-loop circuit is made up of four individual  
elements: a sensor/transducer; a voltage-to-current converter (commonly referred to as a transmitter and/or  
signal conditioner); a loop power supply; and a receiver/monitor. In loop powered applications, all four elements  
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are connected in a closed, series circuit, loop configuration (Figure 41). Sensors provide an output voltage whose  
value represents the physical parameter being measured. The transmitter amplifies and conditions the sensor’s  
output, and then converts this voltage to a proportional 4-20mA dc-current that circulates within the closed  
series-loop. The loop power-supply generally provides all operating power to the transmitter and receiver, and  
any other loop components that require a well-regulated dc voltage. In loop-powered applications, the power  
supply’s internal elements also furnish a path for closing the series loop. The receiver/monitor, normally a  
subsection of a panel meter or data acquisition system, converts the 4-20mA current back into a voltage which  
can be further processed and/or displayed. The high DC performance of the LMP7312 makes this difference  
amplifier an ideal choice for use in current loop AFE receiver. The LMP7312 has a low input offset voltage and  
low input offset voltage drift when configured in amplification mode. In the circuit shown in Figure 41 the  
LMP7312 is in amplification mode with a gain of 2V/V and differential output in order to well match the input  
stage of the ADC141S626 (SAR ADC with differential input). The shunt resistor is 100ohm in order to have a  
max voltage drop of 2V when 20mA flows in the loop. The first order filter between the LMP7312 and the  
ADC141S626 reduces the noise bandwidth and allows handling input signal up to 2kHz. That frequency has  
been calculated taking in account the roll off of the filter and ensuring a gain error less than 1LSB of the  
ADC141S626. In order to utilize the maximum number of bits of the ADC141S626 in this configuration, a 4.1V  
reference voltage is used. With this system, the current of the 4-20mA loop is accurately gained to the full scale  
of the ADC and then digitized for further processing.  
+5V  
+
0.1 mF  
10 mF  
+
V
IO  
V
+5V  
T
R
A
N
S
M
I
T
T
E
R
-V  
IN  
+
1.1kW  
680 pF  
1.1kW  
+V  
OUT  
V
A
V
IO  
-
0.1 mF  
10 mF  
-IN  
+IN  
100W  
ADC141S626  
+
REF  
-V  
/V  
R
OUT  
SENSOR  
I_LOOP  
+5V  
+
LM4132-4.1  
Fs = 70 kS/s  
0.1 mF  
+
V
+
+V  
IN  
4.7 mF  
100 kW  
100 kW  
4.7 mF  
V
OCM  
0.1 mF  
AMPLIFICATION MODE  
G = 2 V/V  
-
-
V
V
Figure 41. LMP7312 in 4-20mA Current Loop application  
LAYOUT CONSIDERATIONS  
Power supply bypassing  
In order to preserve the gain accuracy of the LMP7312, power supply stability requires particular attention. The  
LMP7312 ensures minimum PSRR of 90dB (or 31.62 µV/V). However, the dynamic range, the gain accuracy and  
the inherent low-noise of the amplifier can be compromised by introducing and amplifying power supply noise. To  
decouple the LMP7312 from supply line AC noise, a 0.1 µF ceramic capacitor should be located on the supply  
line, close to the LMP7312. Adding a 10 µF tantalum capacitor in parallel with the 0.1 µF ceramic capacitor will  
reduce the noise introduced to the LMP7312 even further by providing an AC path to ground for most frequency  
ranges.  
22  
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Product Folder Links: LMP7312  
 
LMP7312  
www.ti.com  
SNOSB32B MARCH 2010REVISED MARCH 2013  
APPENDIX  
Offset Voltage and Offset Voltage Drift calculation  
Listed in the table below are the calculated values for Offset Voltage and Offset Voltage Drift based on the max  
specifications of these parameters for the core op-amp (for all gain configurations).  
Parameter  
Unit  
V/V  
Value  
Gain  
0.096  
±1141  
±109  
±32.3  
±3.3  
0.192  
±620  
±119  
±18.6  
±3.6  
0.384  
±360  
±138  
±10.8  
±4.1  
0.768  
±230  
±176  
±6.9  
1
2
Total Offset Input Referred (MAX)  
Total Offset Output Referred (MAX)  
TCVOS Input Referred @ 25°C (MAX)  
TCVOS Output Referred @ 25°C (MAX)  
µV  
±200  
±200  
±6  
±150  
±300  
±4.5  
±9  
µV  
µV/°C  
µV/°C  
±5.3  
±6  
Noise calculation  
Listed in the table below are the calculated values for Voltage Noise based on the spectral density of the core  
op-amp at 10kHz (for all gain configurations).  
Parameter  
Unit  
V/V  
Value  
Gain  
0.096  
211  
20  
0.192  
150  
29  
0.384  
112  
43  
0.768  
89  
1
2
Total Noise Referred to Input  
Total Noise Referred to Output  
nV/Hz  
nV/Hz  
53  
53  
46  
92  
68  
Input resistance calculation  
The common mode input resistance is the resistance seen from node “A” when ΔV1 = ΔV2 = 0 and a common  
mode voltage ΔVCM is applied to both inputs of the LMP7312. The differential input resistance is the resistance  
seen from the nodes “B” and “C” when ΔVCM=0 and a differential voltage ΔV1 = ΔV2 = V/2 is applied to the  
inputs of the LMP7312.  
B
+
-
-
ÂV  
1
A
ÂV  
2
+
-
+
-
+
ÂVCM  
C
Figure 42. Circuit for Input Resistance calculation  
Mode of Operation  
Attenuation Mode  
Unit  
Gains  
0.096  
0.192  
62.08  
0.384  
72.08  
0.768  
92.08  
Common Mode Resistance  
Differential Resistance  
kΩ  
kΩ  
57.08  
228.30  
248.30  
288.30  
368.30  
Amplification Mode  
1
2
Common Mode Resistance  
Differential Resistance  
kΩ  
kΩ  
40.0  
160.0  
60.0  
240.0  
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LMP7312  
SNOSB32B MARCH 2010REVISED MARCH 2013  
www.ti.com  
REVISION HISTORY  
Changes from Revision A (March 2013) to Revision B  
Page  
Changed layout of National Data Sheet to TI format .......................................................................................................... 23  
24  
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Copyright © 2010–2013, Texas Instruments Incorporated  
Product Folder Links: LMP7312  
PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
PACKAGING INFORMATION  
Orderable Device  
Status Package Type Package Pins Package  
Eco Plan  
Lead finish/  
Ball material  
MSL Peak Temp  
Op Temp (°C)  
Device Marking  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4/5)  
(6)  
LMP7312MA/NOPB  
LMP7312MAX/NOPB  
ACTIVE  
SOIC  
SOIC  
D
D
14  
14  
55  
RoHS & Green  
SN  
Level-1-260C-UNLIM  
Level-1-260C-UNLIM  
-40 to 125  
-40 to 125  
LMP7312  
MA  
ACTIVE  
2500 RoHS & Green  
SN  
LMP7312  
MA  
(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.  
(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 finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material 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  
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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.  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
9-Apr-2022  
TAPE AND REEL INFORMATION  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
LMP7312MAX/NOPB  
SOIC  
D
14  
2500  
330.0  
16.4  
6.5  
9.35  
2.3  
8.0  
16.0  
Q1  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
9-Apr-2022  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SOIC 14  
SPQ  
Length (mm) Width (mm) Height (mm)  
356.0 356.0 35.0  
LMP7312MAX/NOPB  
D
2500  
Pack Materials-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
9-Apr-2022  
TUBE  
*All dimensions are nominal  
Device  
Package Name Package Type  
SOIC  
Pins  
SPQ  
L (mm)  
W (mm)  
T (µm)  
B (mm)  
LMP7312MA/NOPB  
D
14  
55  
495  
8
4064  
3.05  
Pack Materials-Page 3  
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