Op amp Definition and 305 Threads
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Upper 3db Frequency of Op Amp Help
So I did the first part, and got the gain as 11. I also did part c, and got approximately 80khz, but I'm not sure what to do for b). I know that at the 3db frequency, the voltage is at 1/20.5 of it's amplitude. So can I just use the equation f=(slew rate)/(2pi*A), and set A to 1V/20.5, and...- mmmboh
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- Amp Frequency Op amp
- Replies: 7
- Forum: Engineering and Comp Sci Homework Help
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Engineering Op Amp Circuit Help: Solving KCL Eq with Source Transform
It was much easier scanning the pictures and problem than trying to recreate: I began by doing a source transform, making Vs = is*Rs, and placing Rs in series instead of parallel. I then did KCL at Vn. I tried to break the KCL eq down to il/is, but just ended up with some un-godly...- wclawson
- Thread
- Amp Circuit Op amp
- Replies: 4
- Forum: Engineering and Comp Sci Homework Help
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Why is there resistor R2 connecting output and input of op amp?
I have attached image. Thanks in advance.- Hyperspace2
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- Amp Input Op amp Output Resistor
- Replies: 12
- Forum: Electrical Engineering
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What is the circuit desighn within op amp?
I am first year student 0f electronics and communication engineering. I have a course called basic electronics. I have already learn't bjt,jfet,mosfet,diff amplifier etc, now its turn of op amp. And I can't move on without knowing what is within op amp. Pictures shows Triangle and +,- within...- Hyperspace2
- Thread
- Amp Circuit Op amp
- Replies: 8
- Forum: Electrical Engineering
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What Is the Name of the Circuit Converting 4-20mA to 1-5V Using an Op Amp?
I have found this circuit in my travels on the internet and it should suit my needs. I need to know what this configuration is called so I can calculate the resistors for the gain needed. If anyone knows of a similar circuit that has trimpots to adjust the 4mA to 1v and the 20mA t0 5v that...- ionut1010
- Thread
- Amp Circuit Op amp
- Replies: 13
- Forum: Electrical Engineering
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Op Amp Voltage Limits: Protecting Your Circuit from Damage
What will happen when the input voltages applied to the op amp is higher than its supplied voltage? Will it damage the op amp?- krispots
- Thread
- Amp Op amp
- Replies: 13
- Forum: Electrical Engineering
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Amplifying WiFi Signal with an Op Amp: Is It Possible?
could one attach an op amp to a wifi transmitter to amplify the signal? thanks.- sdusheyko
- Thread
- Amp Op amp Signal Wifi
- Replies: 2
- Forum: Electrical Engineering
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Inverting OP AMP analysis solution problem
Hello Physics Forums community, I'm a new member and this is my first post. I have a circuits exam tomorrow, and though I grasp the majority of the material I'm having a hard time understanding the solution to a HW problem that I attached as a picture. Problem: Show that the circuit has...- sdusheyko
- Thread
- Amp Analysis Inverting op amp Op amp
- Replies: 1
- Forum: Engineering and Comp Sci Homework Help
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Analysing Op Amp Circuit with a Photo diode
For a lab we built the following circuit. Our photo diode was receiving a blinking signal which our op amp made visible on a DVM. I do not understand the purpose of the capacitors attached to the power rail. So far I understand how negative feed back with the Rf resistor controls the amount...- zimbabwe
- Thread
- Amp Circuit Diode Op amp Photo
- Replies: 2
- Forum: Advanced Physics Homework Help
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Ideal op amp (current to voltage converter + inverting)
Homework Statement Hey there.. need helps here.. The question is.. Derive an expression relating the output voltage, Vo to the input current, Iin. The Attempt at a Solution i try to derive it.. but.. got problem with RL[/size] V1 = -IinRf Vo =- R2/R1(-IinRf) how to include Rl in...- naspek
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- Amp Converter Op amp Voltage
- Replies: 1
- Forum: Engineering and Comp Sci Homework Help
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Design an OP AMP Power Supply for Audio Preamp
Hello, I am trying to design a foundation for an audio preamp that is powered by a single 9V battery. I am successful so far except the single power supply part. I am using the voltage divider scheme to get a +4.5V and a -4.5V reference voltages. With no load the supply voltages are close to...- neg_ion13
- Thread
- Amp Op amp Power Power supply Supply
- Replies: 7
- Forum: Electrical Engineering
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Single Op Amp as a voltage regulator?
Hello all. I was just wondering if it is possible to use an inverting opamp configuration with feedback to regulate an output voltage V0 without the use of BJT's? For example, the following sketch: http://img411.imageshack.us/img411/2389/opamp.png V0 = Vs * (R1-R2) /2R1 Mathematically, V0...- nand_1
- Thread
- Amp Op amp Regulator Voltage Voltage regulator
- Replies: 5
- Forum: Electrical Engineering
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Constant current source using an op amp
I'm currently in the process of building a constant current source using an op amp. Circuit diagram: http://upload.wikimedia.org/wikipedia/en/9/97/Op-amp_current_source_with_pass_transistor.png I'm using a voltage reference instead of a zener diode. Currently the load resistance is 0...- ijmbarr
- Thread
- Amp Constant Current Current source Op amp Source
- Replies: 4
- Forum: Electrical Engineering
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Inverting op amp with positive input NOT grounded
For an inverting op amp with the positive input grounded, the equation for V(out) is (Vin)*Rf/Rin. Thats fine But what if the positive input is not grounded? What if there is a voltage applied to that input as well? How would I find V(out) when the positive input voltage is larger than the...- gotem3303
- Thread
- Amp Input Inverting op amp Op amp Positive
- Replies: 4
- Forum: Engineering and Comp Sci Homework Help
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Choosing an Op Amp for Circuit Triggering
Dear experts, I am thinking of using an op amp to trigger a circuit. The +ve input to the op amp should raise '1' (high) if the voltage is 5v and not anything less. The -ve input to the op amp should always be '0' (low) and so i thin i short it to ground. I wonder what op amp should i...- ramonegumpert
- Thread
- Amp Circuit Op amp
- Replies: 7
- Forum: Electrical Engineering
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Op amp bandwidth and gain problem
Could sb explain to me how to calculate the 3db frequency of the inverting op amp, please? 1. For non-inverting op amp If Bandwidth gain product is 1.5x10^6 Hz and gain is 20dB then the F3db is given by Bandwidth gain product over 20. It equals 150kHz. 2. For inverting op amp the F3db is...- greg997
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- Amp Bandwidth Gain Op amp
- Replies: 2
- Forum: Engineering and Comp Sci Homework Help
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Finding R for Ideal Op Amp to Avoid Saturation
Homework Statement if the op amp satuates at +-14v, determne te the range of values of risitance R for which the op amp does not saturate. Assume the op amp is idal Homework Equations V-=V+ The Attempt at a Solution this is wa i have so far: (2-5/3)+(2-+14/R). not sure if it is...- weedannycool
- Thread
- Amp Op amp Saturation
- Replies: 2
- Forum: Engineering and Comp Sci Homework Help
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Understanding the Behavior of Inverting Op Amp Circuit with Switched Terminals
please look at this circuit http://hyperphysics.phy-astr.gsu.edu/Hbase/Electronic/ietron/inva2.gif The transfer function for the the circuit above is Vout = (-Rf/Rs)*Vs if I were to switch the terminal of the op amp so that Vin is inputted into Vp and Vn =0 instead (everything is the same...- david90
- Thread
- Amp Circuit Inverting op amp Op amp
- Replies: 12
- Forum: Electrical Engineering
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Op Amp Temp Drift: Minimizing Temperature Variations
I'm using an opamp to amplify ac signals 40hz and up but there is still temperature drift, I thought drift was only a problem for dc signals? how do you get rid of temperature drift?- m718
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- Amp Drift Op amp
- Replies: 2
- Forum: Electrical Engineering
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Interfierence with infinite gain op amp
guys I'm making this color sensor.i have used 2 RED LEDs as both sensor and emitter. I have used TL084 op amp in infinite gain mode because Sensor LED generates very small voltage. my problem is op amp is too sensitive so it reacts when i tough circuit or negative wire (some times even my...- aruna1
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- Amp Gain Infinite Op amp
- Replies: 37
- Forum: Electrical Engineering
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Cascading Op Amp: Practical Experience Needed
Hello. I'm looking for someone having practical experience of cascading video amp like NE592 or LM733 in order to get wide bandwidth and huge gain.- Ravaner
- Thread
- Amp Op amp
- Replies: 4
- Forum: Electrical Engineering
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What Components Make Up an Op Amp?
What's inside an op amp? Is it just an npn transistor used for amplification? So can we explain it in the terms of base and collector current? Please elaborate simply (It's a high school project)- uzair_ha91
- Thread
- Amp Op amp
- Replies: 8
- Forum: Electrical Engineering
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Op Amp built with discret components and having GBP over 30 MHz.
Hello, for technical reasons I'm looking for a schematic of an Op Amp built with discret components and having GBP over 30 MHz.- Ravaner
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- Amp Components Op amp
- Replies: 4
- Forum: Electrical Engineering
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Op Amp Current Supply - Is 3 Amps Too Much?
Do opamps have current limit, I have an OP-27 dual supply connected to 2 9V batters the battery measures 3 Amps and 16 volts is this too much current?- m718
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- Amp Current Op amp Supply
- Replies: 7
- Forum: Electrical Engineering
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Using 741C Op Amp with Vcc=+9v and Vee=0: Possible?
If I run a 741C op amp with Vcc=+9v and Vee=0, will it affect the functioning of the op amp? Can I still use it as I normally would? For a 741C Vcc=|Vee|=13v.- chaoseverlasting
- Thread
- Amp Op amp
- Replies: 13
- Forum: Electrical Engineering
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Understanding Op Amp Offset Voltage: Rules & Examples
please can anyone give me clearly information about Op Amp Offset Voltage with simple example and rule to explain that becaus i was found diffecalt to understsnd it .- ecestar
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- Amp Op amp Voltage
- Replies: 11
- Forum: Electromagnetism
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OP07 Op Amp Output Unexpectedly High Voltage
When I connect 3V negative and 3V postive power supply to an OP07 op amp and I Connect a voltmeter to OUT of op amp and GROUND the voltmeter shows -1.8 volts why? I have connected anything to input I even tried shoring the input and this voltage is too high to be offset voltage. I Tried two...- m718
- Thread
- Amp High voltage Op amp Output Voltage
- Replies: 7
- Forum: Electrical Engineering
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OP amp analysis help-exam paper question
Homework Statement i have this exam paper question. derive an expression for transfer function find expression for the magnitude and phase of the response i have attached circuit diagram below 2. The attempt at a solution i derived for first question Vo= 2RC(dVi/dt) -...- aruna1
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- Amp Analysis Op amp Paper
- Replies: 11
- Forum: Engineering and Comp Sci Homework Help
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Choosing a capacitor for an op amp integrator
Hi folks, I've been looking into http://en.wikipedia.org/wiki/Operational_amplifier_applications#Integrator" as a way to add ramps to signals. I'd like to get a ramp rate on the order of 0.1 V/s, which suggests the use of capacitors in the neighborhood of 10-100 uF. Many electrolytic and...- Mapes
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- Amp Capacitor Op amp
- Replies: 2
- Forum: Electrical Engineering
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Op Amp inverting amplifier , help
http://i454.photobucket.com/albums/qq261/integralx2/opamp1.jpg I don't understand why they did something. I found output voltage to be -1.25v , but to find voltage across the 10k resistor, its (Va-Vo)/10k am i correct? cause when i do this and try to calculate the answer for Io its not right...- th3plan
- Thread
- Amp Amplifier Op amp
- Replies: 1
- Forum: Engineering and Comp Sci Homework Help
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Op Amp Circuit Analysis Question: Transfer Function and Ideal Analysis
Homework Statement G'day, the op-amp circuit is attached. Need to know the Transfer Function. Homework Equations Using Ideal analysis. In=Ip=0A, and Vn=Vp Vo/Vi=-15 The Attempt at a Solution I have had many attempts at it. Because We don't know the input current (no input...- priscared
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- Amp Analysis Op amp
- Replies: 2
- Forum: Engineering and Comp Sci Homework Help
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Why do some op amps require capacitors in parallel with supply voltages?
For the INA101, in the configuration for the most basic circuit with the TO-100 package, two 1 mircofarad capacitors seem to be required to be placed in parallel with the supply voltages. Why is this, and is it actually necessary for an operating circuit, since the circuit example with the Dip...- scott_alexsk
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- Amp Op amp
- Replies: 7
- Forum: Electrical Engineering
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Circuits Op Amp R equilvalent help
[SOLVED] Circuits Op Amp R equilvalent help! Homework Statement I'm working on Ideal op amps and I need to find the R equivalent of the system. I'm not sure if this term is used in other places but R equivalent = total Resistance of the circuit...- Innuendo
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- Amp Circuits Op amp
- Replies: 3
- Forum: Introductory Physics Homework Help
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How Do You Calculate the Equivalent Resistance in an Op Amp Circuit?
[SOLVED] Op Amp Requivalent Please help! Homework Statement I'm working on Ideal op amps and I need to find the R equivalent of the system. I'm not sure if this term is used in other places but R equivalent = total Resistance of the circuit. http://img169.imageshack.us/img169/4386/reqrk6.png...- Innuendo
- Thread
- Amp Op amp
- Replies: 4
- Forum: Engineering and Comp Sci Homework Help
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Inductor as a differentiator (op amp)
Homework Statement Sorry this computer doesn't have access to PSPICE and I don't have a scanner, but let's say that I have an op amp. 1) there is a time varying voltage source Vs 2) There is a resistor R1 connected to the inverting input of the op amp 3) The noninverting pin is connected...- jesuslovesu
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- Amp Inductor Op amp
- Replies: 1
- Forum: Engineering and Comp Sci Homework Help
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Engineering Solution to Op Amp Circuit Problem: R1=R2=R3=R5=R
Homework Statement For the following circuit, sketch v2/v1 as a function of R4, if R1=R2=R3=R5=R. Also explain the behaviour of the circuit when R4=R/2. Homework Equations The Attempt at a Solution After solving the circuit, i came up with v2/v1=2R4/(2R4-R). Now, if R4=R/2 ...- farahtc
- Thread
- Amp Circuit Op amp
- Replies: 7
- Forum: Engineering and Comp Sci Homework Help
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Engineering Solve Op Amp Circuit Problem: Find V2/V1 w/Potentiometer
Homework Statement The op amp circuit shown bellow is intended to provide any gain between -10 (for k=0) and +10 (for k=1) by adjusting the potentiometer. Let R1 and R2 have the scaled values, show that.. V2/V1= {r1/(r1+10k)} [-11/{1+(10kr1/r1+10k)}] + [r2/r2+10(1-k)] [1+...- farahtc
- Thread
- Amp Circuit Op amp
- Replies: 1
- Forum: Engineering and Comp Sci Homework Help
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Can anyone recommend an integrator op amp?
Hi, I'm building an integrator using an op-amp to integrate 15 volt 65nS pulses at a repetition rate of 100Khz using a 20uS time constant. Can anyone recommend a suitable op-amp for this application. It needs to have very low input bias current to minimise d.c. drift and have sufficient...- ElecTec
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- Amp Op amp
- Replies: 4
- Forum: Electrical Engineering
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Yet another Op Amp question. Damn I hate these things
For the circuit below, find Vx and Vo. http://www.freewebs.com/mushg/FWThumbnails/OpAmp.bmp- MushManG
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- Amp Op amp
- Replies: 4
- Forum: Engineering and Comp Sci Homework Help
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Understanding the Op Amp Minus Sign Symbol
What does it mean when an op amp has only a minus sign in its symbol? Is the positive terminal at ground, or is it at some arbitrary voltage?- Mindscrape
- Thread
- Amp Op amp Sign Symbol
- Replies: 11
- Forum: Electrical Engineering
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Solving an Op Amp Circuit with Mathematica
Here's my problem: Rs is a resistor whose value depends on temperature. Rs = R0 - 1.8T, where R0 = 5000 ohms and T is in Kelvin. If the ideal op amp has +/- 15 V power rails and you want to maximize the circuit's sensitivity, what should Rf be on the op amp? What is your maximum...- engineer23
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- Amp Mathematica Op amp
- Replies: 2
- Forum: Electrical Engineering
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Second Order Op Amp circuit: Find Vo for t > 0
Homework Statement In the circuit below, determine v_o(t) for t > 0. Let V_{IN}\,=\,u(t)\,V, R_!\,=\,R_2\,=\,10\,k\Omega, C_1\,=\,C_2\,=\,100\,\muF. http://img249.imageshack.us/img249/3840/problem867cg5.jpg Homework Equations i_c\,=\,C\,\frac{dv_c}{dt} The Attempt at a...- VinnyCee
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- Amp Circuit Op amp Second order
- Replies: 1
- Forum: Introductory Physics Homework Help
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Engineering How Does Setting Rx to 60k Affect the Output Voltage in an Ideal Op Amp Circuit?
1. http://img248.imageshack.us/img248/8971/opampanalysisxe2.png Assume that the op amp in the circuit shown is ideal. a.) Find the output voltage when the variable resistor Rx is set to 60k Assuming Ideal Op amp. All currents leaving nodes are negative. V+ = V- = 0 and In = Ip = 0...- shifty101uk
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- Amp Analysis Circuit Circuit analysis Op amp
- Replies: 11
- Forum: Engineering and Comp Sci Homework Help
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Newbie Needs Op Amp Help on Homework Problem
I'm new to op-amps, and would like some guidance. I have a quick question on this HW problem. I'm not asking you to do it for me, but I want to see if my hunch is correct: http://img66.imageshack.us/img66/8872/screenshot01bb7.jpg Now, using ideal op-amp model... I'm going to assume: V+ = V1...- DefaultName
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- Amp Homework Homework problem Op amp
- Replies: 10
- Forum: Engineering and Comp Sci Homework Help
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Designing an Op-Amp with Variable Gain: Need Advice
Homework Statement Design an op-amp that uses a variable 50k ohm resistor. when this variable resistor is at one extreme, the gain is 13, and at the other extreme, the gain is 3. you may use up to 2 op-amps, and up to 7 resistors (including the variable resistor) The Attempt at a Solution...- Number2Pencil
- Thread
- Amp Design Need advice Op amp
- Replies: 9
- Forum: Engineering and Comp Sci Homework Help
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Op Amp Resources: Learn How to Calculate Output Voltage
This may be kind of odd, but this is my first post, so I'm kinda new at this. I need to calculate the output voltage of an op amp with a 2 mA current source inputting into the inverting side, and a ground connected to the inverting input. There is a 1 kiloOhm resistor going across the op amp...- bigaggie
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- Amp Op amp Resources
- Replies: 6
- Forum: Electrical Engineering
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Finding V_o and i_o for an Ideal Op Amp Circuit with Multiple Unknowns
Find V_o and i_o. Assume an ideal op amp. http://img236.imageshack.us/img236/2426/633bb0.jpg I tried applying KCL at v1 and v2 nodes but then got stuck because I had 2 equations with 3 unknowns. \frac{12-v_1}{4} = \frac{v_1-v_2}{8} and \frac{v_1-v_2}{8}+\frac{-10-v_2}{20}= i_o...- Rozenwyn
- Thread
- Amp Op amp
- Replies: 8
- Forum: Engineering and Comp Sci Homework Help
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Combining Summing and Difference Op Amps: Troubleshooting v_+
hey guys, i have a HW problem of a combination of a summing and difference op amp. I got the first few steps of the problem, but i don't know how to continue from where i am. I am having a hard time solving for v_+. any help is greatly appreciatd, maybe if you guys can not solve the problem for...- mugzieee
- Thread
- Amp Difference Op amp
- Replies: 12
- Forum: Engineering and Comp Sci Homework Help
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Will an Op-Amp Output Maximum Voltage with V+ Connected to I+ and V- to I-?
Ok, I just want to see if this would work (but never tried it). Given a standard (though not ideal, let it be real world) op-amp, it has 5 main inputs -- I+, I-, O, V+, V-. If no loops were formed, and V+ was connected to I+ and V- was connected to I-, would the output O always be the...- matejhowell
- Thread
- Amp Function Max Op amp Voltage
- Replies: 2
- Forum: Electrical Engineering
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Understanding Op Amp Node Voltage Analysis: Equation Differences at Node D
Hey, I think I need a little help understanding node voltage analysis with ideal op amps. For the circuit I've attached, at node D, I wrote the equation ((1/1000) + (1/1000))Vd - (1/50000)Vc - (1/1000)Ve = 0 However my prof's equation for node D is: ((1/1000) + (1/1000))Vd - (1/1000)Ve = 0...- seang
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- Amp Node voltage Op amp Voltage
- Replies: 1
- Forum: Electrical Engineering