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...
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...
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...
Homework Statement
Please, I would like to know how to find the factor by which the capacitance is multiplied
A picture of the Op Amp is here: http://en.wikipedia.org/wiki/File:Cap-mult-op.svg
Zc is complex impedance of C
Homework Equations
none given
The Attempt at a Solution...
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...
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...
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...
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
V1 = -IinRf
Vo =- R2/R1(-IinRf) how to include Rl in my...
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...
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...
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...
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...
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...
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...
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...
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...
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?
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...
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)
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.
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 .
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...
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) -...
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...
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...
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...
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...
[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...
[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...
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...
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 ...
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+...
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...
Homework Statement
I have an op amp with two electrode inputs. Each input has 5V of common 60 Hz noise. The size of the signal I want to measure is 9 mV. Signal to noise ratio needs to be 10 to 1.
Homework Equations
I know that CMRR = 20 log (DMG/CMG), where DMG is differential mode...
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...
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...
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...
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...
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...
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...
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...
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...