Presentation on theme: "Selecting the right op amp – Understanding the specifications and navigating through the minefield of products Bob Lee, firstname.lastname@example.org, +44 7718 585."— Presentation transcript:
1 Selecting the right op amp – Understanding the specifications and navigating through the minefield of productsBob 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 ampsProviding gain to small signalsFilteringLevel shiftingADC driverDAC bufferCurrent to voltage converter(transimpedance amplifier)Current source(transconductance amplifier)Common mode noise rejectionPeak voltage detectionSample and holdAbsolute 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-VccAll that differentiates one from another are the specifications – normally many pages of these
8 Op Amp specificationsA typical op amp specification table is long and complicated.All op amp specifications are a tradeoff, improving one specification means relaxing anotherGenerally an op amp is not chosen on any one specification but a combination of themThe ‘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 applicationsThe class we are not discussing is high speed op amps (> 100MHz bandwidth)Much of what follows also applies to high speed op amps as wellHowever, high speed op amps also have many other important factors to consider
12 Keeping it simple Op amp specifications fall into two classes DC parametersAC parametersGenerally 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 stepVery 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, thermistorPressure measurement/strain gaugeECG/EEG etcVoltage/currentApplications 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 DCAny waveform analysisVibration monitoringCable 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 driftInput bias current (Ib)A key careabout in some applications, such as photodiodes but generally not a major concern for most customersNoiseFor low frequency applications its likely to be low frequency, 1/f noise that’s of most concernLets looks at each of these in more detail
15 Input Offset Voltage (Vos) Vout Error 25C Specs in TableOften Histograms show distribution of VosPolarity 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 TableOften Histograms show distribution of Vos DriftPolarity 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 potLaser 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 costE-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 = 5pAIos = 4pAPolarity is + or –Current into or out of inputs
19 Input Bias Current (Ib), Input Offset Current (Ios) 25C Specs in TableOften Curves for Temperature SpecsPolarity 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 Error 2134Input 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 noiseCalculating 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 easierIn 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 noiseIts important to realise that op amps have two voltage noise specsThe broadband noise – that’s the one that headlines in the datasheets.Given in nV/rt HzThe 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 – 10HzThe 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 noise1/f noise corner, the point at which the 1/f noise starts to dominate
24 AC Specifications The main AC specifications of on op amp are:- Gain Bandwith Product - determines the small signal bandwidthSlew Rate - determines the large signal bandwidthNoise, 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 & PhaseOpen-Loop Voltage Gain at DCLinear operation conditions NOT the same as Voltage Output Swing to RailOpen 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 Amps5.5MHz
26 Bandwidth, Small Signal, Bw Op-Amp small signalbandwidth is shown onBode Plot.The -3 dB point for closedloop gain of 10 can bedetermined 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 550kHzHowever, at 550kHz, the loop gain has fallen to zero, it’s the point at which the open loop gain and closed loop gain curves crossIts 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 reductionIn 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 exampleThe 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 20kHzTo retain 20dB of loop gain at 20kHz, we therefore need a gain bandwidth of 2Mhz – this should be considered the mediumBetter 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 swingsThe 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 thisSlew 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 BandwidthRemember that figure given above is the minimum slew rate required. For low distortion, expect to need x5 to x10 this figureSlew 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 datasheetMeasured in nV/rt HzStill 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. Resistanceen density = √ (4kTKR)Noise Spectral Density vs. ResistancenV/rt-HzPeak 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 railsWe 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 isAn op amp only cares about the total voltage across the supply pinsAs far as an op amp is concerned, +/15V is the same as 0-30V and +/-5V is the same as 0 -10VWe 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 groundLikewise 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 featuresThe 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 closethe amplifier can swing to the power supplies (rails).It depends on thetype of Op-Amp...OPA376+-V+V-RloadVinVoutPositive RailNegative Railand the size ofthe load.
39 Voltage Output Swing From Rail Loaded Vout swing from RailHigher Current Load Further from RailNote, its with respect to the railVoltage 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 trendsCMOS op amps, intended for singe supply operation(typically 5V or less) have always had good output swing to the railsBipolar and FET input op amps, intended for supplies of up to +/15V, have in the past had very poor output swing to the railsNormally these parts don’t get closer than 2-3V from the railsThis restricts the use of these parts for lower voltage applicationsMore 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 railsThis 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 RailRail to rail op amps can exceed both railsby 300 mV.OPA376+-V+V-Most Bipolar and JFET Op-Amps cannot get to the rails, some can get to one.VoutVinNegative 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 rangeRemember that in the inverting configuration, the op amp inputs stay at the same voltage irrespective of the input signalThis makes the inverting configuration the low distortion optionThe 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-VccVinVoutFor 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 partProvided 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 upSometimes arises as a power on sequencing issueSometimes 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 suppliesEarly in this presentation we said that all op amp specifications are a compromise, playing off one spec against anotherThis 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 noiseRemember that the load will also draw a current from the supply as well
47 So what’s leftAlmost 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 pointPackage typeAll modern op amps are available in miniature packages but standard SO-8 packages may still be required when second sourcingPricePricing 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 inputsRemedy:External Rs and Cs to Band-limitNew OPA designsseries Rs internallysized to have defined High-f roll-offImproved 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 FamilyThis Low-Noise, Precision, 5.5MHz deviceInput filtering with the corner at approximately 75 MHzOPA378 FamilyLowest noise, Zero-Drift Op Amps with a GBW of 900KHzEMI input filter with a corner frequency of 25MHzOPA369 FamilyThis nano-Power Op Amp has superb DC performanceEMI input filtering with a corner frequency of 25MHz.Great for low power, EMI sensitive applications!OPA333, OPA330 and INA333Zero-Drift devices with outstanding DC precision.EMI inputs filters have a corner frequency of 8MHz.OPA334/335Zero-Drift models with great DC performance with 2MHz GBWEMI filtering with fc =30MHzEMI
51 HPA 36V Op Amps with EMI Filtering OPA170, OPA2170 & OPA4170 (RTM 2Q11)Low 110µA with 1.2MHz bandwidthEMI input filter with a corner frequency of 75 MHzOPA171, OPA2171 & OPA4171 (Available Now)Medium 475µA with 3MHz bandwidthEMI input filter with a corner frequency of 25MHzOPA188, OPA2188 & OPA4188 (RTM 3Q11)Precision Zero-Drift Amplifier 25µV Offset Voltage & 0.1µV/°CEMI 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, SOT553Dual: SO-8, MSOP-8, VSSOP-8Quad: SO-14, TSSOP-14SOT23-53 x 3 x 1.45VSSOP3.1 x 2 x 0.9SOT5531.6 x 1.6 x 0.6
54 Lower cost optionsSome 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 voltageExamplesHigh performance Cost effectiveOPAx OPAx141OPAx OPAx330OPAx OPAx377OPAx OPAx322
55 ? TLC OPA TLV TL Where to start TLE LMV THS LM LMP LME LPV TPA The op amp minefield !TLCOPATLVTL?Where to startTLELMVTHSLMLMPLMELPVTPA
56 Operational Amplifier Naming OPA x 333Channel count0: No character2: dual3: triple4: quad1xx : JFET Input2xx: Bipolar3xx: CMOS4xx: High Voltage5xx: High Outputcurrent6xx: High Speed7xx: High Voltage CMOS (12V)8xx: High Speed(different process than 6xx)OPA Operational AmplifierINA Instrumentation Amplifier andDifference AmplifierLOG Logarithmic AmplifierXTR Current Loop DriverPGA Programable Gain Amplifier (digital)VCA Voltage Controlled Variable Gain AmplifierIVC Current to Voltage Converter
57 Operational Amplifier Naming TLV Low Voltage CMOSTLC CMOSTLE Bipolar / BiFETTL BipolarTHS High SpeedTPA Audio Power AmpsLMLMVNEMCOr could be an SVA part !CommoditySecond Sources
58 Operational Amplifier Naming THS xy 01Amplifier Type30 = Current Feedback31 = Current Feedback40 = Voltage Feedback41 = Fully Differential42 = Voltage Feedback43 = Fast Voltage Feedback45 = Fully Differential46 = Transimpedance60 = Line Receiver61 = Line Driver73 = Programmable FiltersTHS=High Speed
59 Operational Amplifier Naming TL x 278 yAmp ClassV = Low Supply VoltageC = 5V CMOSE = Wide Supply VoltageChannels and Shutdown Options0 = Single with Shutdown1 = Single2 = Dual3 = Dual with Shutdown4 = Quad5 = Quad with Shutdown
60 SVA Amplifier Families Prefixes High PrecisionPure CMOSHiSpeedHigh Speed to Micro PowerMicro PowerLow Powerup to 32VSThe 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 exampleClick 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 chartThe next step is to establish if possible which of the five categories is most appropriate
65 Parametric search(ESP or web) These are the high speed op amps,Separate from the precision parts covered in this presentationClick here to see allprecision op ampsOr choose one of these subsetsWe also have op amps from the HVAL BUThese are covered in a separate parametric search
66 The parametric search page Also other collateral hereRemember 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
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 voltageLMP2021 (5uV max)Lowest bias currentLMP7721 (3 fA typical, 20fA max guaranteed)Lowest quiescent currentLMP521(400nA max)Lowest noiseLME49990(0.9nV/rt Hz)
70 LMP2021/2022 Low Noise Zero Drift Amplifier FeaturesBenefitsLowest Noise Auto Zero Amplifier at Av>500Ultra low drift at 0.004uV/deg C typEMI HardenedIncreased immunity to RFI/EMI disturbancesLow Noise Density11nV/rtLow Vos5uV maxLow DriftTcVos 0.02uV/deg C maxEMI HardenedApplicationsPrecision Instrumentations AmpsBattery Powered InstrumentationThermocouple AmplifiersBridge AmplifiersEVM PART # LMP2021EVAL
71 LMP7721 3 Femptoampere Input Bias Current Precision Op Amp Features BenefitsUltra ultra Low Input Bias Current3 fA typical, 20fA max guaranteedWide operating supply voltage1.8 to 5.5VLow Supply Current1.5mA maxLow Vos only 180uV maxLow Noise Density7nV/rt HzOffers precision performance at very low powerGuaranteed tempco means precision over temperatureCMOS inputs great for high impedance sourcesApplicationsPrecision Instrumentation AmplifiersBattery Powered Medical InstrumentsHigh Impedance SensorsElectrometersEVM PART # LMP7721MAEVALMF/NOPB
72 LPV511/521/531 Micropower/Nanopower Operational Amplifiers FeaturesBenefitsLPV uA supply current, 2.7V to 12V operationRail to Rail Input and OutputSC-70 packageLPV521 World’s Lowest supply current 400nA maxOperates on 1.6V to 5.5V ( V)LPV531 Programmable Isupply 5uA to 435uATSOT23-6 packageMicrowatt Power ConsumptionLong Battery Life in Portable ApplicationsProgrammable supply current (LPV531)Minimum board areaApplicationsBattery powered systemsSecurity systemsMicropower thermostatsSolar powered systemsPortable instrumentationMicropower filterRemote sensor amplifierEVM PART /NOPB
74 Three new 36V OpAmp families High precision, ultra-low noise, industry’s smallest packages JFET inputUltra-low driftLowest noise in classRail-to-rail outputFor applications needing high accuracy and stabilityUltra-low noise2x gain bandwidth of closest competitorRail-to-rail outputFor fast, high-precision data acquisition applicationsOPAx140First in class with rail-to-rail outputFirst in class with quad versionWidest supply range in classApplication examples: High-impedance sensor signal conditioning, medical instrumentation and interfacing with precision data convertersSingle: OPA140; Dual: OPA2140; Quad: OPA4140Samples available now; production quantities of OPA2140 available now; production quantities of OPA140 and OPA4140 available in NovemberOPAx209Best-in-class settling timeApplication examples: Automated test equipment, medical instrumentation and professional audio pre-amplifiersSingle: OPA209; Dual: OPA2209; Quad: OPA4209Samples available now; production quantities of OPA2209 available now; production quantities of OPA209 and OPA4209 available in NovemberOPAx171Best combination of features to simplify general purpose op amp selectionUp 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 operationCost-effectiveApplication examples: Tracking amplifiers in power modules, merchant power supplies, transducer amplifiers and battery-powered test equipmentSingle: OPA171; Dual: OPA2171; Quad: OPA4171Samples available now; production quantities of OPA171 available November; production quantities of OPA2171 and OPA4171 available in DecemberGeneral purposeSOT553: 90% smaller than standard SOIC packageLow powerRail-to-rail outputFor space-constrained industrial applications74
75 much quiescent current ? Looking for…Low IBias OpAmpfor your highimpedance sensor ?OPA140General purposeOpAmp in industriessmallest package ?OPA171Low noise OpAmpWithout burning toomuch quiescent current ?OPA209First HV ZeroDrift OpAmpon the market ?OPA2188
76 OPA171 / OPA2171 / OPA4171 Industry’s smallest 36V Low Power RRO General Purpose Op Amp FeaturesBenefitsIndustry’s smallest 36V Packages:Single in SOT553, Dual in VSSOP-8Micropackages use >50% less board space than the larger SOT23 and MSOP packagesRail to Rail Output+2.7V to +36V or ±1.35V to ±18VHigh CMRR: 104dBLow Noise: 14nV/√Hz at 1kHzMaximizes input voltage range for use with low voltage sensor outputsVersatility in design for ease of use with different supply rail systemsLow Quiescent Current: 475μA/chEnables battery powered operationDC PrecisionOffset Voltage: 1.8mV (max)Offset Voltage Drift: 0.3µV/°CLow Bias Current: 8pAAccuracy and stability over the entire industrial temperature rangeEMI/RFI Filtered InputsImproved noise immunity from wireless interferenceGBW: 3 MHzSlew Rate: 1.5V/µsWide Signal sources and fast response suitable to drive high performance ADCsPackaging options:Single: SO-8, SOT23-5, SOT553Dual: SO-8, MSOP-8, VSSOP-8Quad: SO-14, TSSOP-14ApplicationsTracking Amplifiers in Power ModulesMerchant Power SuppliesTransducer AmplifiersStrain Gage AmplifierPrecision IntegratorBattery Powered InstrumentsSOT23-53 x 3 x 1.45VSSOP3.1 x 2 x 0.9SOT5531.6 x 1.6 x 0.6(Already released / releasing in 3Q’11 )
77 OPA140 / OPA2140 / OPA4140 11MHz, Precision, Low Noise, RRO, JFET Op Amp FeaturesBenefitsVery Low Offset and DriftOffset 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: 11MHzSlew Rate: 20V/μsWide Supply Range:+ 4.5V to +36V or +2.25V to +18VLow power: 2.0mA/chGuaranteed high accuracy and stability over the full industrial temperature rangeAllows for high sensitivity, high resolution systems across a wide frequency rangeBetter matching to high impedance sources such as sensor outputs60% lower IB than previous generation OPA132High GBW and slew rate make it ideal for driving 16-bit ADC’sEnabling low power 5V supply systems13% less power consumption per channel vs. competitionPackaging options:Single: SO-8, MSOP-8, SOT-23Dual: SO-8, MSOP-8Quad: SO-14, TSSOP-14OPAx141 as cost down versions of this partApplicationsSensor Signal ConditioningSecurity ScannerPhotodiode MeasurementActive FiltersMedical Instrumentation
78 OPA209, OPA2209, & OPA4209 2.2nV/√Hz, 18MHz, Precision, RRO, 36V Op Amp FeaturesBenefitsLow Noise : 2.2nV/√Hz at 1kHz (max)1/f Noise: 130nVpp (0.1Hz – 10Hz)Low Offset Voltage: 150µV (max)Gain Bandwidth: 18MHzSlew rate: 6.4V/msWide Supply Range: ±2.25 to ±18V,Single supply: 4.5 to 36VLow Supply Current: 2.5mA/ch maxProvides a low noise solution across full operating frequency rangeIdeal for fast, high precision data acquisition applications and offering 50% wider bandwidth than the competition50% lower minimum voltage supply with rail-to-rail output maximizes dynamic range and provide greater flexibility across designs as compared to the competitionPackaging options:Single: SO-8, MSOP-8, SOT-23Dual: SO-8, MSOP-8Quad: TSSOP-14ApplicationsPLL Loop FilterLow Noise, Low Power Signal ProcessingHigh Performance ADC DriverHigh Performance DAC Output Amplifier.Active FiltersLow Noise Instrumentation Amplifiers
79 OPA188 / OPA2188 / OPA4188 0.03µV/oC, 25µV Vos, 36V Zerø-DriftTM Operational Amplifier FeaturesBenefitsVery Low Offset and DriftOffset Voltage: 25µV (max)Offset Voltage Drift: 0.085µV/°C maxNoise Voltage: 8.8nV/√HzGBW : 2MHzLow Quiescent Current: 475μA (max)Low Bias Current: 850pA (max)Supply Range: +4.0V to +36V or ±2V to ±18VRail to Rail OutputEMI Filtered InputsImproved high accuracy and stability over the previous generation OPA277Offset drift 75% lower than the nearest competitorAllows for high sensitivity, high resolution systems across a wide frequency rangeWell suited for battery powered operationMinimizes errors on the output due to current noiseFlexibility in design, enabling low power 5V supply systemsImproved Noise ImmunityApplicationsPackaging options:Single: SO-8, MSOP-8, SOT-23Dual: SO-8, MSOP-8Quad: SO-14, TSSOP-14• Electronic Weigh ScalesBridge AmplifierStrain Gauge• Automated Test Equipment• Transducer amplifier• Medical Instrumentation• Resistor Thermal Detector(Preview / Already released / sampling, releasing in 3Q’11 )
81 Looking for… Value Line OpAmp with best performance for price ? 16-bit ADC driver thatCombines wide bandwidth andlow distortion with very lowpower ?OPA835/836Cost effective, low powerzero drift op ampOPA330
82 OPA330, 2330, 4330 Single, Dual, Quad, Micro-Power, Zerø-Drift Operational Amplifier Economical alternative to OPA333Low Quiescent Current:25uA (typ), 35µA (max)Low Offset Voltage: 50µV (max)Offset Voltage Drift: 0.25µV/˚C (max)Low Noise: 1.1 µVP-PFlat 1/f NoiseBandwidth: 350kHzRail-to-Rail Input and Output1.8V to 5.5V Supply VoltageOPA330YFF: WCSP – 1.1mm x 0.9mm, 5-ballEMI Input FilteredBest performance/price offering on the market30% lower 1k price than the competitionLow Offset and Zero-Drift Removes needfor CalibrationNo noise related errors especially for near DC and low frequency sensor signal applications.RRIO Increases Dynamic RangeTiny Chip-Scale Package Saves Board Space60% Space Savings over an SC70 packageInput filtering enables precision performance in a RF sensitive environmentBattery-Powered InstrumentsTemperature MeasurementPrecision Strain GagesPrecision Sensor ApplicationsHandheld Test Equipment82
83 OPA835/ OPA2835 Ultra Low Power, RRO, Negative rail in, VFB FeaturesBenefitsUltra Low PowerIq: 250µA/ch, Power-Down: <1uA+2.5V to +5V Single SupplyBandwidth: 56 MHzSlew Rate: 160 V/μsHD2: -105dBc &HD3:Input Voltage Noise: 9.3nV/rtHzRRO – Rail-to-Rail OutputNegative Rail InputPower-Down Capability: <1μASingle and DualStandard packagingAdvanced packaging with integrated resistors for smallest footprint (≈ 2mm x 2mm)Flexible supply for power sensitive applicationsExceptional performance at very low powerIncreased dynamic range / sensitivityLow signal distortionLarger outputs in low voltage applicationsIntegrated gain setting resistors enablessmallest footprint on PCBHigh DensityFlexibilityGains of:+1, -1, +2, -3, +4, -4, +5, -7, +8Non-integer Gains + AttenuationApplicationsLow Power Signal ConditioningLow Power SAR and ΔΣ ADC DriverPortable SystemsLow Power SystemsHigh Density SystemsPackages availableSingle: SOT23-6Single: WQFN -10 (RUN)Dual: SOIC-8Dual: VSSOP-10EVMOPA835 – SOT23Samples AvailableEVMs AvailableOPA835 – RUN838383
84 OPA836/ OPA2836 Ultra Low Power, RRO, Negative rail in, VFB Singles RTM with Duals sampling!FeaturesBenefitsVery Low PowerIq: 1mA/ch, Power-Down: <1uA+2.5V to +5V Single SupplyBandwidth: 205 MHzSlew Rate: 560 V/μsHD2: -120dBc &HD3:Input Voltage Noise: 4.2nV/rtHzVos : 1.08mV (max); Vos drift: 1.1uV/C (typ)RRO – Rail-to-Rail OutputNegative Rail InputSingle and DualStandard packagingAdvanced packaging with integrated resistors for smallest footprint (≈ 2mm x 2mm)Flexible supply for power sensitive applicationsExceptional performance at very low powerIncreased dynamic range / sensitivityLow signal distortionLarger outputs in low voltage applicationsIntegrated gain setting resistors enablessmallest footprint on PCBHigh DensityFlexibilityGains of:+1, -1, +2, -3, +4, -4, +5, -7, +8Non-integer Gains + AttenuationApplicationsLow Power Signal ConditioningLow Power SAR and ΔΣ ADC DriverPortable SystemsLow Power SystemsHigh Density SystemsPackages availableSingle: SOT23-6Single: WQFN -10 (RUN)Dual: SOIC-8Dual: VSSOP-10EVMOPA836 – SOT23Samples AvailableEVMs AvailableOPA836 – RUN848484
85 OPA314 / OPA2314 / OPA4314 Low Cost, 3MHz, 180uA, RRIO CMOS Amplifier Product PreviewFeaturesBenefitsBest combination of Power and PerformanceLow quiescent current: 180µA/ch maxLow Noise: 16nV/√HzInput offset voltage: 2.5mV max.Rail-to-Rail I/OSupply voltage: 1.8V to 5.5VEMI/RFI Input FilterGBW: 3MHzInput bias current: 0.2pAVery low noise at low power is ideal for low-level signal amplifications while maintaining high Signal-to-Noise ratioRRIO maximizes input dynamic range with full use of single supply rangeHigh gain bandwidth for fast pulse responseLow input bias current for high source impedance applicationsApplicationsPackage Options:Single: SC70-5, SOT23-5Dual: MSOP-8, SO-8, DFN-8Quad: TSSOP-14CO/Smoke detectors▪ Photodiode Amplifier▪ Sensor Signal ConditioningLow-Side Current SensePortable Medical and Instrumentation(Preview / Already released / sampling, releasing in 3Q’11 )