OP491 Analog Devices, OP491 Datasheet
OP491
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OP491 Summary of contents
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... Low voltage strain gage amplifiers DAC output amplifiers GENERAL DESCRIPTION The OP191, OP291, and OP491 are single, dual, and quad micropower, single-supply, 3 MHz bandwidth amplifiers featuring rail-to-rail inputs and outputs. All are guaranteed to operate from single supply as well as ±5 V dual supplies. ...
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... OP191/OP291/OP491 TABLE OF CONTENTS Features .............................................................................................. 1 Applications....................................................................................... 1 Pin Configurations ........................................................................... 1 General Description ......................................................................... 1 Revision History ............................................................................... 2 Specifications..................................................................................... 3 Electrical Specifications............................................................... 3 Absolute Maximum Ratings............................................................ 7 Thermal Resistance ...................................................................... 7 ESD Caution.................................................................................. 7 Typical Performance Characteristics ............................................. 8 Theory of Operation ...................................................................... 17 Input Overvoltage Protection ................................................... 18 Output Voltage Phase Reversal................................................. 18 REVISION HISTORY 4/06—Rev Rev. D Changes to Noise Performance, Voltage Density, Table 1........... 3 Changes to Noise Performance, Voltage Density, Table 2 ...
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... T ≤ +125° −40°C ≤ T ≤ +125° kΩ L – kΩ distortion 0.01% S GBP θ kHz kΩ p-p 0 kHz Rev Page OP191/OP291/OP491 Min Typ Max Unit 80 500 μ 700 μ V/mV 50 V/mV 1.1 μV/°C 100 pA/° ...
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... 0 1 Table 2. Parameter INPUT CHARACTERISTICS Offset Voltage OP191 OP291/OP491 Input Bias Current Input Offset Current Input Voltage Range Common-Mode Rejection Ratio Large Signal Voltage Gain Offset Voltage Drift Bias Current Drift Offset Current Drift OUTPUT CHARACTERISTICS Output Voltage High Output Voltage Low ...
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... PSRR V = ± −40°C ≤ T ≤ +125° −40°C ≤ T ≤ +125°C A ± kΩ distortion 0.01% S GBP θ kHz e p-p 0 kHz Rev Page OP191/OP291/OP491 Min Typ Max Unit 80 500 μ 700 μ − 100 V/mV 1.1 μV/°C 100 pA/° ...
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... OP191/OP291/OP491 100 INPUT IN OUTPUT Figure 6. Input and Output with Inputs Overdriven Rev Page ±5V = 2kΩ 20V p-p 200μs ...
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... JA specified for device in socket for PDIP packages; θ for device soldered in circuit board for TSSOP and SOIC packages. Table 5. Thermal Resistance Package Type 8-Lead SOIC (R) 14-Lead PDIP (N) 14-Lead SOIC (R) 14-Lead TSSOP (RU) Rev Page OP191/OP291/OP491 specified JA θ θ Unit JA JC 158 43 ° ...
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... OP191/OP291/OP491 TYPICAL PERFORMANCE CHARACTERISTICS 180 25°C A 160 BASED ON 1200 OP AMPS 140 120 100 –0.18 –0.10 –0.02 0.06 INPUT OFFSET VOLTAGE (mV) Figure 7. OP291 Input Offset Voltage Distribution, V 120 V S –40°C < T 100 BASED ON 600 OP AMPS INPUT OFFSET VOLTAGE (µV/°C) Figure 8. OP291 Input Offset Voltage Drift Distribution, V ...
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... 25°C 140 A 120 100 –45 –20 –90 –40 1M 10M = 0.3V/2. 125 = Rev Page OP191/OP291/OP491 0 10 100 1k 10k 100k FREQUENCY (Hz) Figure 16. Closed-Loop Gain vs. Frequency 100 1k 10k 100k 1M FREQUENCY (Hz) Figure 17. CMRR vs. Frequency – TEMPERATURE (°C) Figure 18. CMRR vs. Temperature 25° 10M = 3 V CMRR ...
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... OP191/OP291/OP491 160 140 120 100 80 60 –PSRR –20 –40 100 1k 10k 100k FREQUENCY (Hz) Figure 19. PSRR vs. Frequency, V 113 112 111 110 109 108 107 –40 25 TEMPERATURE (°C) Figure 20. PSRR vs. Temperature 1.4 +SR 1.2 1.0 0.8 0.6 0.4 –SR 0.2 0 –40 25 TEMPERATURE (°C) Figure 21. Slew Rate vs. Temperature, V ± ...
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... V Figure 29. Input Offset Current vs. Temperature –6 –12 –18 –24 –30 –36 125 = 5 V Figure 30. Input Bias Current vs. Common-Mode Input Voltage Rev Page OP191/OP291/OP491 TEMPERATURE (° TEMPERATURE (° COMMON-MODE INPUT VOLTAGE ( –I B –I ...
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... OP191/OP291/OP491 5.00 4.95 4.90 4. 2kΩ L 4.80 4. 4.70 –40 25 TEMPERATURE (°C) Figure 31. Output Voltage Swing vs. Temperature, V 160 140 120 100 –20 –40 100 1k 10k 100k FREQUENCY (Hz) Figure 32. Open-Loop Gain and Phase vs. Frequency, V 140 R = 100kΩ 120 L CM 100 100kΩ 2kΩ, V ...
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... TEMPERATURE (°C) Figure 38. OP291 Slew Rate vs. Temperature 0.45 0.40 +SR 0.35 –SR 0.30 0.25 0.20 0.15 0.10 0.05 0 – TEMPERATURE (°C) Figure 39. OP491 Slew Rate vs. Temperature ±PSRR 25° –40 1M 10M Figure 40. Short-Circuit Current vs. Temperature ...
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... OP191/OP291/OP491 100 1k 10k FREQUENCY (Hz) Figure 43. Maximum Output Swing vs. Frequency, V 0.15 0. – +5V CM –0.05 –0.10 –40 25 TEMPERATURE (°C) Figure 44. Input Offset Voltage vs. Temperature ± + –10 – –5V CM –30 –40 –50 –40 25 TEMPERATURE (°C) Figure 45. Input Bias Current vs. Temperature 9.8V p-p ...
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... V S 160 V = ±5V S 140 T = 25°C A 120 100 –20 –40 1M 10M 100 = ± Rev Page OP191/OP291/OP491 CMRR 10k 100k 1M FREQUENCY (Hz) Figure 52. CMRR vs. Frequency ± ± TEMPERATURE (°C) Figure 53. CMRR vs. Temperature, V =± ±PSRR +PSRR –PSRR 1k 10k 100k 1M FREQUENCY (Hz) Figure 54. PSRR vs. Frequency ± ...
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... OP191/OP291/OP491 115 V = ±5V S 110 OP291 105 100 95 90 –40 25 TEMPERATURE (°C) Figure 55. OP291/OP491 PSRR vs. Temperature ±5V S 0.6 +SR 0.5 –SR 0.4 0.3 0.2 0.1 0 –40 25 TEMPERATURE (°C) Figure 56. Slew Rate vs. Temperature +100 V 100 0.1 1k 10k 100k FREQUENCY (Hz) Figure 57. Output Impedance vs. Frequency ...
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... THEORY OF OPERATION The OP191/OP291/OP491 are single-supply, micropower amplifiers featuring rail-to-rail inputs and outputs. To achieve wide input and output ranges, these amplifiers employ unique input and output stages. In Figure 61 , the input stage comprises two differential pairs, a PNP pair and an NPN pair. These two stages do not work in parallel ...
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... V, internal PN junctions energize, allowing current to flow from the input to the supplies. As described, the OP291/OP491 do have 5 kΩ resistors in series with each input to help limit the current. Calculating the slope of the current vs. voltage in the graph confirms the 5 kΩ resistor. ...
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... SINGLE-SUPPLY RTD AMPLIFIER The circuit in Figure 66 uses three op amps of the OP491 to develop a bridge configuration for an RTD amplifier that operates from a single 5 V supply. The circuit takes advantage of the OP491 wide output swing range to generate a high bridge excitation voltage of 3 ...
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... OP191/OP291/OP491 A 2.5 V REFERENCE FROM SUPPLY In many single-supply applications, the need for a 2.5 V reference often arises. Many commercially available monolithic 2.5 V references require a minimum operating supply voltage The problem is exacerbated when the minimum operating system supply voltage The circuit illustrated in Figure example of a 2.5 V reference that operates from a single 3 V supply ...
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... OP291 0° 300°C Figure 71. Single-Supply, Direct Access Arrangement for Modems The OP491 bandwidth of 3 MHz and rail-to-rail output swings ensure that it can provide the largest possible drive to the transformer at the frequency of transmission. Rev Page OP191/OP291/OP491 390pF 37.4kΩ 20kΩ,1% ...
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... C6 μF capacitor, without oscillation. C6 maintains a low impedance ac ground over the operating frequency range of the filter. The filter section uses a pair of OP491s in a twin-T configuration whose frequency selectivity is very sensitive to the relative matching of the capacitors and resistors in the twin-T section. Mylar is the material of choice for the capacitors, and the relative matching of the capacitors and resistors determines the pass band symmetry of the filter ...
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... MAX 0.130 (3.30) 0.115 (2.92) PIN 1 1.05 0.014 (0.36) 1.00 0.010 (0.25) 0.80 0.008 (0.20) 0.430 (10.92) MAX Rev Page OP191/OP291/OP491 8.75 (0.3445) 8.55 (0.3366 6.20 (0.2441) 5.80 (0.2283 1.27 (0.0500) 1.75 (0.0689) BSC 1.35 (0.0531) 0.51 (0.0201) SEATING ...
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... OP291GSZ-REEL 1 OP291GSZ-REEL7 OP491GP 1 OP491GPZ OP491GS OP491GS-REEL OP491GS-REEL7 1 OP491GSZ 1 OP491GSZ-REEL OP491GSZ-REEL7 1 OP491GRU-REEL 1 OP491GRUZ-REEL OP491GBC Pb-free part. ©2006 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. Temperature Range Package Description −40°C to +125°C 8-Lead SOIC − ...