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Selecting the right op amp – Understanding the specifications and navigating through the minefield of products 1 Bob Lee, +44 7718 585.

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Presentation on theme: "Selecting the right op amp – Understanding the specifications and navigating through the minefield of products 1 Bob Lee, +44 7718 585."— Presentation transcript:

1 Selecting the right op amp – Understanding the specifications and navigating through the minefield of products 1 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? 3 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 ? + - +Vcc -Vcc All that differentiates one from another are the specifications – normally many pages of these 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

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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

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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 ? 13 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 –

16 Input Offset Voltage (Vos) Drift  Vout Error Vos Drift Specs in Table Often Histograms show distribution of Vos Drift Polarity is + or -

17 Input offset voltage reduction 17 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) 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 –

20 Input Bias Current (Ib)  Vout Error

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

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

23 Good 1/f noise example 23

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 Open Loop Gain & Phase Gain-Bandwidth Product = UGBW (Unity Gain Bandwidth) G=1 Stable Op Amps 5.5MHz Open-Loop Voltage Gain at DC Linear operation conditions NOT the same as Voltage Output Swing to Rail

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 27 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 28 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 29 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 30 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

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

33 Broadband noise 33 50nV/rt-Hz 5nV/rt-Hz The broadband noise 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 Noise Spectral Density vs. Resistance Resistance (Ohms)Noise Spectral Density vs. Resistance nV/rt-Hz √ e n density = √ (4kT K R) Resistor Noise – Thermal Noise 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 37 ‘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 OPA V+ V- R load V in V out Positive Rail Negative Rail Output Swing refers to how close the amplifier can swing to the power supplies (rails). It depends on the type of Op-Amp... 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

40 Output stage trends 40 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, OPA 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 OPA V+ V- V out Positive Rail Negative Rail V in Input Voltage Range refers to how close the input is allowed to get to the rails. Most Bipolar and JFET Op-Amps can not get to the rails, some can get to one. Rail to rail op amps can exceed both rails by 300 mV.

43 Input voltage range 43 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 With respect to the rails again

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 45 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)

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 EMIRR Application Note: AN-1698 "A specification for EMI Hardened Op Amps" A

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

54 Lower cost options 54 Examples High performance Cost effective OPAx140 OPAx141 OPAx333 OPAx330 OPAx376 OPAx377 OPAx320 OPAx322 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

55 The op amp minefield ! 55

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 TLVLow Voltage CMOS TLCCMOS TLEBipolar / BiFET TLBipolar THSHigh Speed TPAAudio Power Amps LM LMV NE MC Commodity Second Sources Or could be an SVA part !

58 Operational Amplifier Naming THS xy 01 THS=High Speed 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

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 Low Power up to 32V S Micro Power High Speed to Micro Power The last digit indicated singe/dual/quad, i.e LMC6442 is a dual

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

62 Block diagram example 62 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) 65 Or choose one of these subsets We also have op amps from the HVAL BU These are covered in a separate parametric search These are the high speed op amps, Separate from the precision parts covered in this presentation Click here to see all precision op amps

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

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

68 Some key op amps 68

69 Best in class products from the SVA portfolio 69 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 EVM PART # LMP2021EVAL  Low Noise Density  11nV/rt  Low Vos  5uV max  Low Drift  TcVos 0.02uV/deg C max  EMI Hardened  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  Precision Instrumentations Amps  Battery Powered Instrumentation  Thermocouple Amplifiers  Bridge Amplifiers LMP2021/2022 Low Noise Zero Drift Amplifier

71 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 Precision Instrumentation Amplifiers Battery Powered Medical Instruments High Impedance Sensors Electrometers LMP Femptoampere Input Bias Current Precision Op Amp EVM PART # LMP7721MAEVALMF/NOPB

72 EVM PART /NOPB 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) Rail to Rail Input and Output SC-70 package 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 Battery powered systems Security systems Micropower thermostats Solar powered systems Portable instrumentation Micropower filter Remote sensor amplifier LPV511/521/531 Micropower/Nanopower Operational Amplifiers

73 73 © 2010 National Semiconductor Corporation. Confidential. 73 © 2010 National Semiconductor Corporation. Confidential. 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 600  loads PSRR and CMRR exceed 100dB Output short-circuit protection Winning Specs GBW 110MHz Slew Rate +22V/  s THD % Input Noise 0.9nV/rtHz Operating Voltage + 5V to + 18V PSRR 144dB CMRR 137dB

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 For space- constrained industrial applications General purpose SOT553: 90% smaller than standard SOIC package Low power Rail-to-rail output

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

76 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/chEnables 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 InputsImproved 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 OPA171 / OPA2171 / OPA4171 Industry’s smallest 36V Low Power RRO General Purpose Op Amp Tracking Amplifiers in Power Modules Merchant Power Supplies Transducer Amplifiers Strain Gage Amplifier Precision Integrator Battery Powered Instruments Packaging options: Single: SO-8, SOT23-5, SOT553 Dual: SO-8, MSOP-8, VSSOP-8 Quad: SO-14, TSSOP-14 SOT x 3 x 1.45 VSSOP 3.1 x 2 x 0.9 SOT x 1.6 x 0.6 (Already released / releasing in 3Q’11 )

77  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 OPA140 / OPA2140 / OPA MHz, Precision, Low Noise, RRO, JFET Op Amp Sensor Signal Conditioning Security Scanner Photodiode Measurement Active Filters Medical Instrumentation Packaging options: Single: SO-8, MSOP-8, SOT-23 Dual: SO-8, MSOP-8 Quad: SO-14, TSSOP-14  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 I B 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 OPAx141 as cost down versions of this part

78 OPA209, OPA2209, & OPA nV/√Hz, 18MHz, Precision, RRO, 36V Op Amp 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 PLL Loop Filter Low Noise, Low Power Signal Processing High Performance ADC Driver High Performance DAC Output Amplifier. Active Filters Low Noise Instrumentation Amplifiers 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/  s Wide Supply Range: ±2.25 to ±18V, Single supply: 4.5 to 36V Low Supply Current: 2.5mA/ch max Packaging options: Single: SO-8, MSOP-8, SOT-23 Dual: SO-8, MSOP-8 Quad: TSSOP-14

79 Packaging options: Single: SO-8, MSOP-8, SOT-23 Dual: SO-8, MSOP-8 Quad: SO-14, TSSOP-14 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 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 ) OPA188 / OPA2188 / OPA µV/ o C, 25µV Vos, 36V Zerø-DriftTM Operational Amplifier

80 New Low voltage op amps

81 Looking for… 16-bit ADC driver that 16-bit ADC driver that Combines wide bandwidth and Combines wide bandwidth and low distortion with very low distortion with very low power ? power ? OPA835/836 Value Line OpAmp Value Line OpAmp with best performance with best performance for price ? for price ? OPA2314 Cost effective, low power Cost effective, low power zero drift op amp zero drift op amp OPA330

82 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 µV P-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 OPA330, 2330, 4330 Single, Dual, Quad, Micro-Power, Zerø-Drift Operational Amplifier Battery-Powered Instruments Temperature Measurement Precision Strain Gages Precision Sensor Applications Handheld Test Equipment 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

83 OPA835/ OPA2835 Ultra Low Power, RRO, Negative rail in, VFB 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) Low Power Signal Conditioning Low Power SAR and ΔΣ ADC Driver Portable Systems Low Power Systems High Density Systems 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 EVM Samples Available EVMs Available Gains of: +1, -1, +2, -3, +4, -4, +5, -7, +8 Non-integer Gains + Attenuation OPA835 – RUN OPA835 – SOT23 Packages available Single: SOT23-6 Single: WQFN -10 (RUN) Dual: SOIC-8 Dual: VSSOP-10

84 OPA836/ OPA2836 Ultra Low Power, RRO, Negative rail in, VFB 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) Low Power Signal Conditioning Low Power SAR and ΔΣ ADC Driver Portable Systems Low Power Systems High Density Systems 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 EVM Samples Available EVMs Available Gains of: +1, -1, +2, -3, +4, -4, +5, -7, +8 Non-integer Gains + Attenuation OPA836 – RUN OPA836 – SOT23 Singles RTM with Duals sampling! Packages available Single: SOT23-6 Single: WQFN -10 (RUN) Dual: SOIC-8 Dual: VSSOP-10

85 OPA314 / OPA2314 / OPA4314 Low Cost, 3MHz, 180uA, RRIO CMOS Amplifier Package Options: Single: SC70-5, SOT23-5 Dual: MSOP-8, SO-8, DFN-8 Quad: TSSOP-14 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 CO/Smoke detectors ▪ Photodiode Amplifier ▪ Sensor Signal Conditioning Low-Side Current Sense Portable Medical and Instrumentation (Preview / Already released / sampling, releasing in 3Q’11 )


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