1. Selecting the right op amp – Understanding the specifications and navigating through the minefield of products
Bob Lee,

2. Where to look for op amps ??
Op amps are the fundamental analog building block and are most commonly found between the analog input or sensor and the ADC and between the DAC and the analog output or actuator

3. What are op amps used for?
Some of the uses for op amps
Providing gain to small signals
Filtering
Level shifting
ADC driver
DAC buffer
Current to voltage converter(transimpedance amplifier)
Current source(transconductance amplifier)
Common mode noise rejection
Peak voltage detection
Sample and hold
Absolute value circuit

4. So what’s so difficult about op amp selection ?
Selecting the right op amp for your customers application, just how hard can that be ?
The first problem is that all op amps basically look the same, with 5 pins + -
+Vcc
-Vcc
All that differentiates one from another are the specifications – normally many pages of these

8. Op Amp specifications
A typical op amp specification table is long and complicated.
All op amp specifications are a tradeoff, improving one specification means relaxing another
Generally an op amp is not chosen on any one specification but a combination of them
The ‘perfect op amp’ doesn’t exist !
In order to be able to effectively support these products and help customers with product selection we need to be able to identify which parameters are most important and to have at least a basic understanding of these

9. Ideal Operational Amplifier
Using our derived concepts of how an op amp operates and assuming an ideal op amp we can derive the theoretical gain equation for Vout/Vin for an inverting op amp configuration. With infinite Aol and an external feedback network the op amp +input and –input are forced to equal each other. In the inverting gain configuration the +input is ground and therefore the +input is forced to zero volts or to “virtual ground”. From nodal analysis we easily derive the standard inverting gain equation for an op amp of Vout/Vin = - RF/RI.

10. Ideal Operational Amplifier
Using our derived concepts of how an op amp operates and assuming an ideal op amp we can derive the theoretical gain equation for Vout/Vin for a non-inverting op amp configuration. With infinite Aol and an external feedback network the op amp +input and –input are forced to equal each other. From nodal analysis we easily derive the standard non-inverting gain equation for an op amp of Vout/Vin = 1 + RF/RI.

11. Limitation of the exercise
In order to keep things simpler we will limit this discussion to general purpose op amps(‘precision’ op amps)
This covers to majority of op amp applications
The class we are not discussing is high speed op amps (> 100MHz bandwidth)
Much of what follows also applies to high speed op amps as well
However, high speed op amps also have many other important factors to consider

12. Keeping it simple Op amp specifications fall into two classes
DC parameters
AC parameters
Generally speaking, customer applications require good DC performance or good AC performance but not both. Appreciating which of these classes of specifications are going to be important is a good first step
Very often it will be obvious which is going to be most important from the application, but if in doubt, then just ask the customer !

13. DC or AC performance ?
Applications that will requires good DC performance generally have small amplitude, low bandwidth signals. These include:-
Most temperature measurement, thermocouple, RTD, PT100, thermistor
Pressure measurement/strain gauge
ECG/EEG etc
Voltage/current
Applications that require good AC performance have wide bandwidth signals and generally care more about peak to peak amplitude rather than about absolute voltage levels. Examples include:-
Audio – you can’t hear DC
Any waveform analysis
Vibration monitoring
Cable detection

14. DC Specifications The main DC specifications are :-
Offset voltage (Vos) and drift (dVos/dt)
These tend to be related, parts with a low offset also have a low offset drift
Input bias current (Ib)
A key careabout in some applications, such as photodiodes but generally not a major concern for most customers
Noise
For low frequency applications its likely to be low frequency, 1/f noise that’s of most concern
Lets looks at each of these in more detail

15. Input Offset Voltage (Vos)  Vout Error
25C Specs in Table
Often Histograms show distribution of Vos
Polarity is + or –
Input Offset Voltage is the inherent offset voltage due to non-ideal devices and mis-matches inside of the real op amp. The effect of this can be see with the op amp in inverting configuration and the +input grounded. Ideally Vout would be zero volts. For the real op amp Vout becomes Vos times closed loop gain. The input offset voltage can be either positive or negative. Often the data sheet will include an Offset Voltage Distribution histogram to indicate how the Offset Voltage typically varies over a wide number of units.

16. Input Offset Voltage (Vos) Drift  Vout Error
Vos Drift Specs in Table
Often Histograms show distribution of Vos Drift
Polarity is + or -
Offset Voltage Drift is an additional input offset voltage which is added to Vos depending upon the operating temperature of the op amp relative to 25C. A distribution of the Vos Drift may be shown in histogram form to indicate how Vos Drift will typically be different over a wide number of parts.

17. Input offset voltage reduction
Remember this ?
The untrimmed offset on the LM741 is 6mV and the drift is 15uV/C !
Hence the need for the trim pot
Laser trimming replaces the offset trim pot with internal laser trimmed resistors and enables an offset of 20uV and drift of 0.1uV/C(OPA277) – but at a cost
E-trim replaces the laser trimmed resistors with trim fuses, blown once at the factory during test to produce cost effective parts with an offset of 25uV and drift of 0.26uV/C (OPA376)
Auto zero and chopping techniques reduce this to 5uV and 0.001uV/C (LMP2021)

18. Input Bias Current (Ib), Input Offset Current (Ios)
Input bias current is the input current into or out of the +input and –input of the op amp required for the input stages of the op amp to function properly. Unless specified the current could be either into or out of the op amp inputs. Industry standard definition of input bias current is the average of current into the +input and –input. Input offset current is defined as the difference between the input bias current of the +input and the input bias current of the –input.
Ib = 5pA
Ios = 4pA
Polarity is + or –
Current into or out of inputs

19. Input Bias Current (Ib), Input Offset Current (Ios)
25C Specs in Table
Often Curves for Temperature Specs
Polarity is + or –
Input Bias Current and Input Offset Current are usually specified in the Electrical Characteristics Table for 25C operation. Often the change in input bias current over temperature is shown as a curve in the Typical Characteristics

20. Input Bias Current (Ib)  Vout Error2 1 3 4
Input bias current flows through any resistance on the +input or –input of the op amp. This current flow creates an offset voltage on the input to the op amp and will be multiplied by the op amp closed loop gain as an error voltage at the output. To analyze this additional offset voltage set all voltage sources in the circuit to zero volts. Set the op amp output to zero volts since it is viewed as low impedance at DC. For the non-inverting op amp configuration this results in the Ib- flowing through the parallel combination of RF and RI. Ib+ flows through the input source resistance, Rs. Two offset voltages, Vb+ and Vb-, on the op amp inputs can be created. The equivalent offset voltage error due to Ib can be lumped into Vb = Vb+ - Vb- and this lumped offset voltage is gained up as an error on Vout by the closed loop gain of the op amp.

21. Op Amp noise
Calculating the total noise generated by an op amp and the associated resistors is a complex subject and outside of the scope of this presentation. However there are some things we can do to make it easier
In the same way that most customers are more concerned about offset voltage rather than input bias current, most customers are more concerned about voltage noise than they are current noise
Its important to realise that op amps have two voltage noise specs
The broadband noise – that’s the one that headlines in the datasheets.
Given in nV/rt Hz
The 1/f noise – probably more important in the low frequency applications where DC accuracy is the main careabout.
Given as an rms or peak to peak voltage, 0.1 – 10Hz
The left hand curve is the voltage spectral density curve. It has a 1/f and broadband region. The right hand curve is the open loop gain (Aol) curve. The bandwidth of the circuit is determined by the Aol curve because there is no other filter. The calculation shows that the bandwidth is 158kHz; this can also be seen graphically.

22. Op Amp noise spectrum 50nV/rt-Hz 5nV/rt-Hz The 1/f noise
The broadband noise
1/f noise corner, the point at which the 1/f noise starts to dominate

23. Good 1/f noise example

24. AC Specifications The main AC specifications of on op amp are:-
Gain Bandwith Product - determines the small signal bandwidth
Slew Rate - determines the large signal bandwidth
Noise, now it’s the broadband noise that will dominate rather than the 1/f noise

25. Gain-Bandwidth Product = UGBW (Unity Gain Bandwidth)
Open Loop Gain & Phase
Open-Loop Voltage Gain at DC
Linear operation conditions NOT the same as Voltage Output Swing to Rail
Open Loop Gain & Phase will be used to compute gain accuracy at any frequency of interest as well as how stable the op amp is when the loop is closed with feedback for a resistive load. Open Loop Gain is usually measured with Vout a specified drop away from the power supply rails. The op amp may be capable of swinging closer to the rails than where the Open Loop Gain is specified but the op amp will not have as high of open loop gain and other non-linearities may occur.
Gain-Bandwidth Product = UGBW (Unity Gain Bandwidth)
G=1 Stable Op Amps
5.5MHz

26. Bandwidth, Small Signal, Bw
Op-Amp small signal
bandwidth is shown on
Bode Plot.
The -3 dB point for closed
loop gain of 10 can be
determined using the Bode Plot.

27. The importance of loop gain
Loop gain is the difference between the desired closed loop gain (i.e. that set by the feedback resistors) and the op amps open loop gain (its gain in the absence of feedback)

28. The importance of loop gain
For the part shown on the previous slide, the gain bandwidth product was 5.5Mhz. At a gain of 20db(x10) this implies a small signal bandwidth of 550kHz
However, at 550kHz, the loop gain has fallen to zero, it’s the point at which the open loop gain and closed loop gain curves cross
Its loop gain that enables an op amp to do its job and for AC applications this primarily means reduce distortion.
No loop gain = no distortion reduction
In order to have some loop gain always in hand we need to use an op amp with much more bandwidth than is implied by multiplying gain by required bandwidth, to get to a gain bandwidth figure(GBW)
10 x GBW gives 20 dB loop gain in hand – still not very much
` 100 x GBW gives 40 dB – that's more like it

29. Loop gain example
The customer has an audio application and requires a 20kHz bandwidth. He also requires a gain of 20dB(x10)
The minimum gain bandwidth required is therefore 200kHz, however as we have just seen, this would leave no loop gain at 20kHz
To retain 20dB of loop gain at 20kHz, we therefore need a gain bandwidth of 2Mhz – this should be considered the medium
Better would be to go for 40dB of loop bandwidth, this implies a gain bandwidth of 20MHz.
Notice, the difference between the customers system bandwidth (20kHz) and the gain bandwidth of the op amp required (20MHz)

30. Small signal and large signal requirements
The previous discussion on loop gain and bandwidth assumes small signal swings
The means that we are assuming that the op amps output stage can actually swing (slew) fast enough to support a sine wave of that frequency. Keeping the signals small ensures this
Slew rate may well limit the output peak to peak voltage swing at high frequencies. We need to check this next

31. Slew Rate Slew Rate Measurement: 10% to 90% of Vout
Slew Rate is a large signal transfer function of an op amp. It is a rate-of-change of the output for a large step voltage on the input. The accepted measurement points for delta Vout are 10% and 90%. The delta t (time) it takes to transition between these two voltage points is used to compute slew rate.

32. Full Power Bandwidth
Remember that figure given above is the minimum slew rate required. For low distortion, expect to need x5 to x10 this figure
Slew Rate is also used to determine the frequency and magnitude limitations of passing a large signal sinewave through an op amp. Maximum Output Voltage vs Frequency plot shows these frequency-amplitude limitations. This curve is also know as Power Bandwidth or Full Power Bandwidth curve.

33. Broadband noise 50nV/rt-Hz The broadband noise 5nV/rt-Hz
Its now the broadband noise that care about, the number on the first page of the datasheet
Measured in nV/rt Hz
Still not as simple as it seems since we have to understand what is meant by the bandwidth(depends on the filter order of the system) and may in any case be dominated by resistor noise

34. Resistor Noise – Thermal Noise
Noise Spectral Density vs. Resistance
en density = √ (4kTKR)
Noise Spectral Density vs. Resistance
nV/rt-Hz
Peak to Peak noise, such as that as seen on an oscilloscope can be estimated by applying a scale factor to RMS noise calculations. This chart was generated using the equation given in the last slide. Note that the equation was divided by the square root of bandwidth to give a spectral density. This chart is useful because it gives you a quick way of comparing resistor noise to op-amp noise. Most op-amps specify noise in nV/rtHz. So, for example a very low noise amplifier may have a 1nV/rtHz noise. This corresponds to approximately 70ohms on the curve above. Thus, for this example, op-amp you should try to keep resistance below 70ohms.
Resistance (Ohms)
Low noise circuits need low value resistors !

35. Selecting the right part
The main DC and AC specifications are the first step to selecting the right op amp for the job.
But its not the end of the story !
We now have to consider the power supplies and the input and output voltage swings with respect to the rails
We need to know the supply voltage(s) the customer intends to use and his expectation on output voltage swing and input voltage range

36. Power Supplies +Vcc + - -Vcc
An op amp doesn’t have a ground pin, it has no knowledge of where ground is
An op amp only cares about the total voltage across the supply pins
As far as an op amp is concerned, +/15V is the same as 0-30V and +/-5V is the same as 0 -10V
We do have to take care that the inputs operate within the allowed voltage range which will be with respect to –Vcc for the lower limit and with respect to +Vcc for the upper limit. Not with respect to ground
Likewise we have to ensure that the op amp can provide the required output swing which will be with respect to it’s supply rails

37. Rail to Rail I/0
‘Rail to rail inputs’ and ‘Rail to Rail outputs’ are terms much beloved by marketing and customers often ask for these features
The problem is that ‘rail to rail’ means different things to different people, so always ask the customer to be very specific :-
What supply voltage(s) is the op amp operating from ?
How close to the –ve rail do the inputs need to operate ?
How close to the +ve rail do the inputs need to operate ?
What’s the load and where is it connected ? Then :-
How close to the –ve rail does the output have to swing ?
How close to the +ve rail does the output have to swing ?

38. Output Voltage Swing - Rail-to-Rail Output
Output Swing refers to how close
the amplifier can swing to the power supplies (rails).
It depends on the
type of Op-Amp...
OPA376 + - V+ V-
Rload
Vin
Vout
Positive Rail
Negative Rail
and the size of
the load.

39. Voltage Output Swing From Rail
Loaded Vout swing from Rail
Higher Current Load  Further from Rail
Note, its with respect to the rail
Voltage Output Swing from Rail is an indication of output voltage swing capability of the op amp as it has to provide current into a load. The larger current required for the load the further away from the rails the op amp will swing. This curve is based on saturating the output transistors to get as close to the rails as possible. If one is trying to operate on a point directly on top of one of these curves then there is potential for higher gain errors as this is in anon-linear region of the output stage of the op and Aol is degraded.

40. Output stage trends
CMOS op amps, intended for singe supply operation(typically 5V or less) have always had good output swing to the rails
Bipolar and FET input op amps, intended for supplies of up to +/15V, have in the past had very poor output swing to the rails
Normally these parts don’t get closer than 2-3V from the rails
This restricts the use of these parts for lower voltage applications
More modern parts are much better in this respect and this enables the parts to be used for both high and low supply voltage applications

41. Wide supply voltage range, OPA171
For a high voltage (36V) op amp, these are very good figures and allow its use over a wide supply voltage range. The part is useful on +/-15V and single 3.3V rails
This actually confuses the selection process since for a low voltage application, you may well have to check out some of the new high voltage parts as well !
The OPAx171 is a very versatile, cost effective op amp, happy on single 5V as well as +/- 15V

42. Input Voltage Range - Rail-to-Rail Input
Input Voltage Range refers to how close the input is allowed to get to the rails.
Positive Rail
Rail to rail op amps can exceed both rails
by 300 mV.
OPA376 + - V+ V-
Most Bipolar and JFET Op-Amps can
not get to the rails, some can get to one.
Vout
Vin
Negative Rail

43. Input voltage range With respect to the rails again
This is the OPA171 who’s output voltage range we looked at earlier. Although its output voltage swing will allow a wide supply voltage range, we would still have to be careful about the input voltage range
Remember that in the inverting configuration, the op amp inputs stay at the same voltage irrespective of the input signal
This makes the inverting configuration the low distortion option
The non-inverting configuration is much more difficult since the op amp inputs move with the signal, more so at low gains, the worst case being a unity gain buffer

44. Unity gain buffer, the problem+ -
+Vcc
-Vcc
Vin
Vout
For the unity gain buffer, the swing on Vout is the same as the swing on Vin and both op amp inputs need to be able to accommodate this. If Vout has a large swing (‘rail to rail’), then the inputs need to be able to swing rail to rail

45. Inputs outside of the rails
Most op amps can operate with inputs slightly outside of the rails.
Going further outside of the rails, will turn on the internal ESD cells. With no current limiting this will damage the cells and damage the part
Provided however that the current is limited to few mA(<10mA), input signals outside of the rails are acceptable. The part won’t operate correctly but it won’t sustain damage or latch up
Sometimes arises as a power on sequencing issue
Sometimes a voltage spikes issue

46. How about the current consumpsion ?
What we are concerned with here is current drawn by the op amp from the supplies
Early in this presentation we said that all op amp specifications are a compromise, playing off one spec against another
This is very true of quiescent current. Don’t expect low current op amps to have the best performance in other aspects, in particular bandwidth and noise
Remember that the load will also draw a current from the supply as well

47. So what’s left
Almost home a dry on op amp selection, what’s left to think about ?
Other features ?
EMI/RFI hardening. Many of the HPA and SVA op amps now have this feature. This can make life much easier for your customer and be a key selling point
Package type
All modern op amps are available in miniature packages but standard SO-8 packages may still be required when second sourcing
Price
Pricing is outside of the scope of this presentation but many new op amps are available as two part numbers, one being a lower cost option (typically relaxed offset spec)

48. OP Amps and EMI EMI/RFI may cause Vos shifts, noise
Most dominant if seen by OPA inputs
Remedy:
External Rs and Cs to Band-limit
New OPA designs
series Rs internally
sized to have defined High-f roll-off
Improved and predicable EMI rejection

49. Newer Op-amps have built-in EMI filtering(EMIRR)
Reducing an operational-amplifier’s EMI susceptibility now may include an integrated input filter. A low-pass filter is created by using the input differential pair junction capacitances, and a small series resistances in the input paths. Since the differential pair exhibits both differential and common-mode capacitances the filter is effective for filtering both types of EMI.
An equivalent filter is shown having total differential and common-mode capacitances of 2.5pF and 5.0pF, respectively, and 1kΩ series input resistors. The filter response plot reveals a first-order, low-pass response, and a -3dB cutoff frequency of 32MHz. Both differential and common-mode cutoff frequencies are the same for the capacitance and resistance values used.
The actual unity-gain bandwidth of the operational-amplifier is commonly be a few Megahertz, so the low-pass filter cutoff frequency is well above it. That prevents the EMI filter from becoming a factor in the operational-amplifier’s normal AC response. However, the cutoff frequency is low enough to be effective in filtering of 100MHz and higher.
The series resistances are selected to set the filter’s cutoff frequency, yet must be keep low in value so as not to degrade the amplifier’s low noise performance.

50. HPA LV Op Amps with internal EMI filtering
OPA376/377 Family
This Low-Noise, Precision, 5.5MHz device
Input filtering with the corner at approximately 75 MHz
OPA378 Family
Lowest noise, Zero-Drift Op Amps with a GBW of 900KHz
EMI input filter with a corner frequency of 25MHz
OPA369 Family
This nano-Power Op Amp has superb DC performance
EMI input filtering with a corner frequency of 25MHz.
Great for low power, EMI sensitive applications!
OPA333, OPA330 and INA333
Zero-Drift devices with outstanding DC precision.
EMI inputs filters have a corner frequency of 8MHz.
OPA334/335
Zero-Drift models with great DC performance with 2MHz GBW
EMI filtering with fc =30MHz
EMI

51. HPA 36V Op Amps with EMI Filtering
OPA170, OPA2170 & OPA4170 (RTM 2Q11)
Low 110µA with 1.2MHz bandwidth
EMI input filter with a corner frequency of 75 MHz
OPA171, OPA2171 & OPA4171 (Available Now)
Medium 475µA with 3MHz bandwidth
EMI input filter with a corner frequency of 25MHz
OPA188, OPA2188 & OPA4188 (RTM 3Q11)
Precision Zero-Drift Amplifier 25µV Offset Voltage & 0.1µV/°C
EMI input filter with a corner frequency of 25MHz.
EMI

52. SVA EMIRR Application Note
AN-1698
"A specification for EMI Hardened Op Amps" A

53. Smaller packages, OPAx171 Packaging options:
Single: SO-8, SOT23-5, SOT553
Dual: SO-8, MSOP-8, VSSOP-8
Quad: SO-14, TSSOP-14
SOT23-5
3 x 3 x 1.45
VSSOP
3.1 x 2 x 0.9
SOT553
1.6 x 1.6 x 0.6

54. Lower cost options
Some parts are now offered with one part number for the high performance option and a different part number for a more cost effective option. Normally the main difference is in DC specifications such as offset voltage
Examples
High performance Cost effective
OPAx OPAx141
OPAx OPAx330
OPAx OPAx377
OPAx OPAx322

55. ? TLC OPA TLV TL Where to start TLE LMV THS LM LMP LME LPV TPA
The op amp minefield !
TLC
OPA
TLV TL ?
Where to start
TLE
LMV
THS LM
LMP
LME
LPV
TPA

56. Operational Amplifier Naming
OPA x 333
Channel count
0: No character
2: dual
3: triple
4: quad
1xx : JFET Input
2xx: Bipolar
3xx: CMOS
4xx: High Voltage
5xx: High Outputcurrent
6xx: High Speed
7xx: High Voltage CMOS (12V)
8xx: High Speed
(different process than 6xx)
OPA Operational Amplifier
INA Instrumentation Amplifier and
Difference Amplifier
LOG Logarithmic Amplifier
XTR Current Loop Driver
PGA Programable Gain Amplifier (digital)
VCA Voltage Controlled Variable Gain Amplifier
IVC Current to Voltage Converter

57. Operational Amplifier Naming
TLV Low Voltage CMOS
TLC CMOS
TLE Bipolar / BiFET
TL Bipolar
THS High Speed
TPA Audio Power Amps LM
LMV NE MC
Or could be an SVA part !
Commodity
Second Sources

58. Operational Amplifier Naming
THS xy 01
Amplifier Type
30 = Current Feedback
31 = Current Feedback
40 = Voltage Feedback
41 = Fully Differential
42 = Voltage Feedback
43 = Fast Voltage Feedback
45 = Fully Differential
46 = Transimpedance
60 = Line Receiver
61 = Line Driver
73 = Programmable Filters
THS=High Speed

59. Operational Amplifier Naming
TL x 278 y
Amp Class
V = Low Supply Voltage
C = 5V CMOS
E = Wide Supply Voltage
Channels and Shutdown Options
0 = Single with Shutdown
1 = Single
2 = Dual
3 = Dual with Shutdown
4 = Quad
5 = Quad with Shutdown

60. SVA Amplifier Families Prefixes
High Precision
Pure CMOS
HiSpeed
High Speed to Micro Power
Micro Power
Low Power
up to 32VS
The last digit indicated singe/dual/quad, i.e LMC6442 is a dual

61. Where to start looking ?
One starting point would be the applications block diagrams in ESP

62. Block diagram example
Click on the op amp symbol for initial suggestions of parts for this application

63. ESP Master Presentation
While not the definitive way of selecting the right part, the majority of op amp selections can be done by using the XY charts highlighted in the Master Presentation slide above. These will at least give a starting point to be going from.
The first step is to establish the supply voltage. 5V or less and look at the low voltage charts, above 5V and it’s the high voltage chart
The next step is to establish if possible which of the five categories is most appropriate

64. Low Voltage - Low Offset Voltage

65. Parametric search(ESP or web)
These are the high speed op amps,
Separate from the precision parts covered in this presentation
Click here to see all
precision op amps
Or choose one of these subsets
We also have op amps from the HVAL BU
These are covered in a separate parametric search

66. The parametric search page
Also other collateral here
Remember that one option is to download the table to Excel and then sort and search it yourself.

67. Parametric Search – Excel download
Add your own filters or sorting

68. Some key op amps

69. Best in class products from the SVA portfolio
The SVA portfolio introduces some parts with a performance that TI didn’t previously have. Some of the key parts here are :-
Lowest offset voltage
LMP2021 (5uV max)
Lowest bias current
LMP7721 (3 fA typical, 20fA max guaranteed)
Lowest quiescent current
LMP521(400nA max)
Lowest noise
LME49990(0.9nV/rt Hz)

70. LMP2021/2022 Low Noise Zero Drift Amplifier
Features
Benefits
Lowest Noise Auto Zero Amplifier at Av>500
Ultra low drift at 0.004uV/deg C typ
EMI Hardened
Increased immunity to RFI/EMI disturbances
Low Noise Density
11nV/rt
Low Vos
5uV max
Low Drift
TcVos 0.02uV/deg C max
EMI Hardened
Applications
Precision Instrumentations Amps
Battery Powered Instrumentation
Thermocouple Amplifiers
Bridge Amplifiers
EVM PART # LMP2021EVAL

71. LMP7721 3 Femptoampere Input Bias Current Precision Op Amp Features
Benefits
Ultra ultra Low Input Bias Current
3 fA typical, 20fA max guaranteed
Wide operating supply voltage
1.8 to 5.5V
Low Supply Current
1.5mA max
Low Vos only 180uV max
Low Noise Density
7nV/rt Hz
Offers precision performance at very low power
Guaranteed tempco means precision over temperature
CMOS inputs great for high impedance sources
Applications
Precision Instrumentation Amplifiers
Battery Powered Medical Instruments
High Impedance Sensors
Electrometers
EVM PART # LMP7721MAEVALMF/NOPB

72. LPV511/521/531 Micropower/Nanopower Operational Amplifiers
Features
Benefits
LPV uA supply current, 2.7V to 12V operation
Rail to Rail Input and Output
SC-70 package
LPV521 World’s Lowest supply current 400nA max
Operates on 1.6V to 5.5V ( V)
LPV531 Programmable Isupply 5uA to 435uA
TSOT23-6 package
Microwatt Power Consumption
Long Battery Life in Portable Applications
Programmable supply current (LPV531)
Minimum board area
Applications
Battery powered systems
Security systems
Micropower thermostats
Solar powered systems
Portable instrumentation
Micropower filter
Remote sensor amplifier
EVM PART /NOPB

73. LME49990 Ultra Low-Distortion, Low- Noise Audio Op Amp
Voltage Noise Density
Winning Features
Extremely low 1/f noise enables flicker free operation
Easily drives 600W loads
PSRR and CMRR exceed 100dB
Output short-circuit protection
Winning Specs
GBW 110MHz
Slew Rate +22V/ms
THD %
Input Noise 0.9nV/rtHz
Operating Voltage + 5V to + 18V
PSRR 144dB
CMRR 137dB
LME49990 is the flagship high performance op amp in our portfolio. It is an industry leading device with lowest THDN of % and sub one nV noise density (best-in-class) and PSRR and CMRR well exceeding the 100dB. You can take a look at the specs on the datasheet but I’d like to point your attention towards its extremely low 1/f noise that is depicted in this graph and as you can see, unlike competitive devices, the noise level does not take a sharp upturn once it hits the corner frequency and as a result it will lead to flicker-free operation.
You can take a look at the target applications including ultra high quality audio amplification, high fidelity filters, medical ultrasound preamps, and sigma-delta converter buffers. So really, this part can be employed anywhere within the signal chain that requires precise amplification or filtering,
© 2010 National Semiconductor Corporation. Confidential.
© 2010 National Semiconductor Corporation. Confidential. 73 73 73 73

74. Three new 36V OpAmp families High precision, ultra-low noise, industry’s smallest packages
JFET input
Ultra-low drift
Lowest noise in class
Rail-to-rail output
For applications needing high accuracy and stability
Ultra-low noise
2x gain bandwidth of closest competitor
Rail-to-rail output
For fast, high-precision data acquisition applications
OPAx140
First in class with rail-to-rail output
First in class with quad version
Widest supply range in class
Application examples: High-impedance sensor signal conditioning, medical instrumentation and interfacing with precision data converters
Single: OPA140; Dual: OPA2140; Quad: OPA4140
Samples available now; production quantities of OPA2140 available now; production quantities of OPA140 and OPA4140 available in November
OPAx209
Best-in-class settling time
Application examples: Automated test equipment, medical instrumentation and professional audio pre-amplifiers
Single: OPA209; Dual: OPA2209; Quad: OPA4209
Samples available now; production quantities of OPA2209 available now; production quantities of OPA209 and OPA4209 available in November
OPAx171
Best combination of features to simplify general purpose op amp selection
Up to 90% smaller than industry-standard packaging: First 36-V op amp offered in SOT553 (single) and VSSPO-8 (dual)
Low-power for battery-powered operation
Cost-effective
Application examples: Tracking amplifiers in power modules, merchant power supplies, transducer amplifiers and battery-powered test equipment
Single: OPA171; Dual: OPA2171; Quad: OPA4171
Samples available now; production quantities of OPA171 available November; production quantities of OPA2171 and OPA4171 available in December
General purpose
SOT553: 90% smaller than standard SOIC package
Low power
Rail-to-rail output
For space-constrained industrial applications 74

75. much quiescent current ?
Looking for…
Low IBias OpAmp
for your high
impedance sensor ?
OPA140
General purpose
OpAmp in industries
smallest package ?
OPA171
Low noise OpAmp
Without burning too
much quiescent current ?
OPA209
First HV Zero
Drift OpAmp
on the market ?
OPA2188

76. OPA171 / OPA2171 / OPA4171 Industry’s smallest 36V Low Power RRO General Purpose Op Amp
Features
Benefits
Industry’s smallest 36V Packages:
Single in SOT553, Dual in VSSOP-8
Micropackages use >50% less board space than the larger SOT23 and MSOP packages
Rail to Rail Output
+2.7V to +36V or ±1.35V to ±18V
High CMRR: 104dB
Low Noise: 14nV/√Hz at 1kHz
Maximizes input voltage range for use with low voltage sensor outputs
Versatility in design for ease of use with different supply rail systems
Low Quiescent Current: 475μA/ch
Enables battery powered operation
DC Precision
Offset Voltage: 1.8mV (max)
Offset Voltage Drift: 0.3µV/°C
Low Bias Current: 8pA
Accuracy and stability over the entire industrial temperature range
EMI/RFI Filtered Inputs
Improved noise immunity from wireless interference
GBW: 3 MHz
Slew Rate: 1.5V/µs
Wide Signal sources and fast response suitable to drive high performance ADCs
Packaging options:
Single: SO-8, SOT23-5, SOT553
Dual: SO-8, MSOP-8, VSSOP-8
Quad: SO-14, TSSOP-14
Applications
Tracking Amplifiers in Power Modules
Merchant Power Supplies
Transducer Amplifiers
Strain Gage Amplifier
Precision Integrator
Battery Powered Instruments
SOT23-5
3 x 3 x 1.45
VSSOP
3.1 x 2 x 0.9
SOT553
1.6 x 1.6 x 0.6
(Already released / releasing in 3Q’11 )

77. OPA140 / OPA2140 / OPA4140 11MHz, Precision, Low Noise, RRO, JFET Op Amp
Features
Benefits
Very Low Offset and Drift
Offset Voltage: 120μV (max)
Offset Drift: 1µV/°C (max)
Low Noise: 5.1nV/√Hz (1kHz)
1/f Noise: 250nVpp (0.1-10Hz)
FET Input: Ib = 10pA (max)
GBW: 11MHz
Slew Rate: 20V/μs
Wide Supply Range:
+ 4.5V to +36V or +2.25V to +18V
Low power: 2.0mA/ch
Guaranteed high accuracy and stability over the full industrial temperature range
Allows for high sensitivity, high resolution systems across a wide frequency range
Better matching to high impedance sources such as sensor outputs
60% lower IB than previous generation OPA132
High GBW and slew rate make it ideal for driving 16-bit ADC’s
Enabling low power 5V supply systems
13% less power consumption per channel vs. competition
Packaging options:
Single: SO-8, MSOP-8, SOT-23
Dual: SO-8, MSOP-8
Quad: SO-14, TSSOP-14
OPAx141 as cost down versions of this part
Applications
Sensor Signal Conditioning
Security Scanner
Photodiode Measurement
Active Filters
Medical Instrumentation

78. OPA209, OPA2209, & OPA4209 2.2nV/√Hz, 18MHz, Precision, RRO, 36V Op Amp
Features
Benefits
Low Noise : 2.2nV/√Hz at 1kHz (max)
1/f Noise: 130nVpp (0.1Hz – 10Hz)
Low Offset Voltage: 150µV (max)
Gain Bandwidth: 18MHz
Slew rate: 6.4V/ms
Wide Supply Range: ±2.25 to ±18V,
Single supply: 4.5 to 36V
Low Supply Current: 2.5mA/ch max
Provides a low noise solution across full operating frequency range
Ideal for fast, high precision data acquisition applications and offering 50% wider bandwidth than the competition
50% lower minimum voltage supply with rail-to-rail output maximizes dynamic range and provide greater flexibility across designs as compared to the competition
Packaging options:
Single: SO-8, MSOP-8, SOT-23
Dual: SO-8, MSOP-8
Quad: TSSOP-14
Applications
PLL Loop Filter
Low Noise, Low Power Signal Processing
High Performance ADC Driver
High Performance DAC Output Amplifier.
Active Filters
Low Noise Instrumentation Amplifiers

79. OPA188 / OPA2188 / OPA4188 0.03µV/oC, 25µV Vos, 36V Zerø-DriftTM Operational Amplifier
Features
Benefits
Very Low Offset and Drift
Offset Voltage: 25µV (max)
Offset Voltage Drift: 0.085µV/°C max
Noise Voltage: 8.8nV/√Hz
GBW : 2MHz
Low Quiescent Current: 475μA (max)
Low Bias Current: 850pA (max)
Supply Range: +4.0V to +36V or ±2V to ±18V
Rail to Rail Output
EMI Filtered Inputs
Improved high accuracy and stability over the previous generation OPA277
Offset drift 75% lower than the nearest competitor
Allows for high sensitivity, high resolution systems across a wide frequency range
Well suited for battery powered operation
Minimizes errors on the output due to current noise
Flexibility in design, enabling low power 5V supply systems
Improved Noise Immunity
Applications
Packaging options:
Single: SO-8, MSOP-8, SOT-23
Dual: SO-8, MSOP-8
Quad: SO-14, TSSOP-14
• Electronic Weigh Scales
Bridge Amplifier
Strain Gauge
• Automated Test Equipment
• Transducer amplifier
• Medical Instrumentation
• Resistor Thermal Detector
(Preview / Already released / sampling, releasing in 3Q’11 )

80. New Low voltage op amps

81. Looking for… Value Line OpAmp with best performance for price ?
16-bit ADC driver that
Combines wide bandwidth and
low distortion with very low
power ?
OPA835/836
Cost effective, low power
zero drift op amp
OPA330

82. OPA330, 2330, 4330 Single, Dual, Quad, Micro-Power, Zerø-Drift Operational Amplifier
Economical alternative to OPA333
Low Quiescent Current:
25uA (typ), 35µA (max)
Low Offset Voltage: 50µV (max)
Offset Voltage Drift: 0.25µV/˚C (max)
Low Noise: 1.1 µVP-P
Flat 1/f Noise
Bandwidth: 350kHz
Rail-to-Rail Input and Output
1.8V to 5.5V Supply Voltage
OPA330YFF: WCSP – 1.1mm x 0.9mm, 5-ball
EMI Input Filtered
Best performance/price offering on the market
30% lower 1k price than the competition
Low Offset and Zero-Drift Removes need
for Calibration
No noise related errors especially for near DC and low frequency sensor signal applications.
RRIO Increases Dynamic Range
Tiny Chip-Scale Package Saves Board Space
60% Space Savings over an SC70 package
Input filtering enables precision performance in a RF sensitive environment
Battery-Powered Instruments
Temperature Measurement
Precision Strain Gages
Precision Sensor Applications
Handheld Test Equipment 82

83. OPA835/ OPA2835 Ultra Low Power, RRO, Negative rail in, VFB
Features
Benefits
Ultra Low Power
Iq: 250µA/ch, Power-Down: <1uA
+2.5V to +5V Single Supply
Bandwidth: 56 MHz
Slew Rate: 160 V/μs
HD2: -105dBc &HD3:
Input Voltage Noise: 9.3nV/rtHz
RRO – Rail-to-Rail Output
Negative Rail Input
Power-Down Capability: <1μA
Single and Dual
Standard packaging
Advanced packaging with integrated resistors for smallest footprint (≈ 2mm x 2mm)
Flexible supply for power sensitive applications
Exceptional performance at very low power
Increased dynamic range / sensitivity
Low signal distortion
Larger outputs in low voltage applications
Integrated gain setting resistors enables
smallest footprint on PCB
High Density
Flexibility
Gains of:
+1, -1, +2, -3, +4, -4, +5, -7, +8
Non-integer Gains + Attenuation
Applications
Low Power Signal Conditioning
Low Power SAR and ΔΣ ADC Driver
Portable Systems
Low Power Systems
High Density Systems
Packages available
Single: SOT23-6
Single: WQFN -10 (RUN)
Dual: SOIC-8
Dual: VSSOP-10
EVM
OPA835 – SOT23
Samples Available
EVMs Available
OPA835 – RUN 83 83 83

84. OPA836/ OPA2836 Ultra Low Power, RRO, Negative rail in, VFB
Singles RTM with Duals sampling!
Features
Benefits
Very Low Power
Iq: 1mA/ch, Power-Down: <1uA
+2.5V to +5V Single Supply
Bandwidth: 205 MHz
Slew Rate: 560 V/μs
HD2: -120dBc &HD3:
Input Voltage Noise: 4.2nV/rtHz
Vos : 1.08mV (max); Vos drift: 1.1uV/C (typ)
RRO – Rail-to-Rail Output
Negative Rail Input
Single and Dual
Standard packaging
Advanced packaging with integrated resistors for smallest footprint (≈ 2mm x 2mm)
Flexible supply for power sensitive applications
Exceptional performance at very low power
Increased dynamic range / sensitivity
Low signal distortion
Larger outputs in low voltage applications
Integrated gain setting resistors enables
smallest footprint on PCB
High Density
Flexibility
Gains of:
+1, -1, +2, -3, +4, -4, +5, -7, +8
Non-integer Gains + Attenuation
Applications
Low Power Signal Conditioning
Low Power SAR and ΔΣ ADC Driver
Portable Systems
Low Power Systems
High Density Systems
Packages available
Single: SOT23-6
Single: WQFN -10 (RUN)
Dual: SOIC-8
Dual: VSSOP-10
EVM
OPA836 – SOT23
Samples Available
EVMs Available
OPA836 – RUN 84 84 84

85. OPA314 / OPA2314 / OPA4314 Low Cost, 3MHz, 180uA, RRIO CMOS Amplifier
Product Preview
Features
Benefits
Best combination of Power and Performance
Low quiescent current: 180µA/ch max
Low Noise: 16nV/√Hz
Input offset voltage: 2.5mV max.
Rail-to-Rail I/O
Supply voltage: 1.8V to 5.5V
EMI/RFI Input Filter
GBW: 3MHz
Input bias current: 0.2pA
Very low noise at low power is ideal for low-level signal amplifications while maintaining high Signal-to-Noise ratio
RRIO maximizes input dynamic range with full use of single supply range
High gain bandwidth for fast pulse response
Low input bias current for high source impedance applications
Applications
Package Options:
Single: SC70-5, SOT23-5
Dual: MSOP-8, SO-8, DFN-8
Quad: TSSOP-14
CO/Smoke detectors
▪ Photodiode Amplifier
▪ Sensor Signal Conditioning
Low-Side Current Sense
Portable Medical and Instrumentation
(Preview / Already released / sampling, releasing in 3Q’11 )