Questions tagged [non-inverting]
The non-inverting tag has no usage guidance.
115
questions
9
votes
6answers
2k views
Why put a resistor in series with the positive terminal in a non inverting op-amp circuit?
I've tried to find the answer, but failed.
Why do we add R1 in series with the positive terminal for a non-inverting amplifier? What is the best value we can assume or choose for it?
0
votes
2answers
54 views
non-inverting current sense op amp output unstable during the measurement
I would like some advice on how to solve the following problem. The following circuit is motor driver with current sense circuit. The circuit run motor at cca 30mV when is not under load, but when the ...
0
votes
1answer
60 views
Stereo channel strip based on NE5532
I want to build a stereo channel strip, using the NE5532 IC. It should feature 2 mono inputs with volume control, mute switch and pan control going to a stereo output with unity gain. In the schematic ...
0
votes
2answers
42 views
Am I measuring the Op-amp MCP6004 IC output voltage correctly using Arduino
Right now I am testing an MCP6004 Op-amp IC. A sensor in my main circuit going to give me a signal in the range 0-0.5 V max. So, I want to amplify this in the 0-5V range so that my Arduino reads it ...
0
votes
2answers
66 views
Motion Sensor Design
I'm trying to design a motion sensor alarm. If there is movement in my house, the motion sensor will send out a signal which will be connected to an alarm that will make a loud noise. I'm currently ...
3
votes
3answers
156 views
How to analyze this opamp circuit?
So with the following circuit (currently studying for an exam):
I am able to get V- just through the voltage divider composed of 2R and R at the non inverting terminal. However, once there, I am ...
3
votes
2answers
112 views
Non-ideal Non-inverting op amp
This is probably more of an algebra question.
I do not understand where the "1"s come from in equation 1.10 given the much simpler voltage divider equation in the line just above it. And why ...
0
votes
0answers
67 views
Amplify 1kHz sine wave from AD9833 DDS using LMH6609 operational amplifier
I'm trying to amplify a 1kHz sine wave signal from the AD9833 DDS chip (0.6Vp-p) to a more usable level (6Vp-p) for a sort of function generator. I plan to work with higher frequencies as well. So I ...
0
votes
1answer
71 views
Non Inverting Op Amp output near power supply voltage when input voltage is at 0V
I have a simple non inverting op amp circuit.
I am using this to amplify a DC voltage. The positive input voltage will vary from 0V-5V.
My problem is that regardless of the input the output is about ...
0
votes
1answer
54 views
Why does my single-supply non-inverting amplifier produce a wierd shape (depending on earphones)?
I built this circuit:
It is based on this design for a single-supply non inverting amplifier:
When I tested my output waveforms with earphone A I got normal results:
When I used earphone B, I got ...
0
votes
1answer
34 views
How impedance levels affect a non-inverting amplifier?
I need help understanding what the highlighted section means. I mainly want to understand how it determines the current drain when using difference resistance to get the same gain, and how it affects ...
0
votes
0answers
20 views
How would you calculate the input impedances of these circuits? [duplicate]
How would you calculate input impedance of this circuit?
I have tried and obtained these calculations for 1.3, but apparently my teacher told me that I am supposed to ignore the 2 10k resistors. This ...
0
votes
1answer
42 views
Combining inverting and non inverting opamps
I have a circuit:
Assuming the op-amps are ideal, how do I derive an expression of Vout in terms of A and B?
I set B to 0 and worked out that the output of the opamp connected to A is 9A, and by ...
2
votes
1answer
45 views
Inverting Amplifier Circuit using Single Power Rail
For my homework, we are supposed to simulate an inverting and noninverting amplifier using a single supply and the LM324 opamp. I built the inverting amplifier using a voltage divider, but my output ...
2
votes
1answer
77 views
Op Amp Selection Help for Rail/ Rail IO
I am looking for an operational amplifier which will fit my requirements.
My circuit consists of two cascaded non-inverting amplifiers.I have a classical non-inverting setup.The minus pin of both ...
0
votes
2answers
67 views
Problem in controlling the device temperature using an op-amp
OBJECTIVE:
I have a device to which voltage is applied and this voltage has to be controlled according to the temperature detected by the thermistor that is placed on the device. If the temperature of ...
-1
votes
2answers
167 views
transfer function of non-inverting op.amp circuit
I am trying to find the transfer function H(s)= Vo(s)/R2(s) but i am struggling to get it. I am assuming an ideal op-amp. V+=V- and that no current flows through the pins op the op.amp.
simulate this ...
0
votes
3answers
208 views
Why is the output impedance of a non-inverting op amp zero? [closed]
Also is it actually zero or just very low?
1
vote
1answer
228 views
Op amp output voltage offset too high
While building an opamp based non-inverting amplifier for my project I noticed that it always has some considerable output voltage despite having the input at zero. To verify that problem I built the ...
0
votes
2answers
96 views
Difference between two gain +1 op-amp topologies
I've got two differential driver circuit designs that take a single ended input and provide as output a buffered pair of +1 and -1 times the input and I'm struggling to understand the difference ...
0
votes
1answer
634 views
NE5532 opamp on amplifier circuit
The picture below is named as headphone amplifier on the internet. My goal is not to do "headphone amplifier". I want to design an analog frontend with a bandwidth of 10 MHz for ADC input. This ...
5
votes
6answers
6k views
Single supply opamp with AC coupling
I am trying to make an amplifier with an opamp, using a single supply.
I found lots of ressources online. This response was very informative and I tried to simulate this circuit.
Let's say that I ...
0
votes
2answers
82 views
Op amp output DC operating point variation with load current
Consider a cmos op amp in non inverting configuration. For a small load current, we expect the output DC voltage to be the input DC voltage multiplied by closed loop gain. As the load current is ...
0
votes
1answer
49 views
Line input circuit
I'm trying to design an unbalanced line input for an audio device using a single supply. I would like the input stage to provide variable gain between 0 and 2.
This is what I have come up with so far:...
0
votes
1answer
87 views
Limit the current draw from Op-Amp
Following up on this question I redesigned my circuit with the suggestions from the comments (see comments from @Andy_aka). I want to drive the output of the opamp between 0-24V with an Vin = 0-10V. I ...
0
votes
1answer
176 views
Why is the output signal greater than the input signal in this voltage follower circuit?
I have implemented this circuit on my breadboard.
The voltage waveform at point A and B in the circuit attached below should be equal because it's a voltage follower, but in my case, after ...
1
vote
1answer
285 views
Is this Non-Inverting integrator correct?
I've seen time again the formula for an inverting integrator. I was wondering if I could swap the configurations on the inverting and non inverting inputs of the op amp to make the circuit a non-...
1
vote
2answers
146 views
What is the gain in a non-inverting amplifier
I am unsure if I am tackling this problem correctly. The input signal is connected to terminal E4 and the output signal is observed at terminal E9
What is the voltage gain when E1 is connected?
What ...
0
votes
3answers
169 views
Non-inverting amplifier with negative supply rail
simulate this circuit – Schematic created using CircuitLab
The formula Vout = Vin * (1 + R2 / R1) is not valid for this case? because for example I'm feeding ...
1
vote
2answers
92 views
Calculation of noise in Non inverting Op-amp circuit
I have this non inverting op-amp circuit:
I would like to calculate the output with the Op-amp noise impact.
I can easily find the voltage output, but only if I assume there is no noise.
How to do ...
0
votes
2answers
1k views
Non-inverting amplifier with variable gain from 1 to 15
I need to design a non-inverting amplifier with gain from 1 (unity) to 15. From what I read, in theory this can be achieved by using a pot as the feedback resistor, but in practice this will only work ...
0
votes
1answer
86 views
Design of Low Pass Filter
So I have made a low pass filter and plotted the transfer function of it. However, I know I need to also use another opamp to correct the phase shifting/ gain. What design should be best to add on to ...
4
votes
1answer
237 views
Non-inverting op-amp saturating incorrectly
Background
Hello, I'm trying to amplify an audio signal using an LM324N in a non-inverting configuration. I'm not trying to build an audio amplifier to drive speakers, I just need to amplify it a bit ...
0
votes
1answer
868 views
Floating input in Op-amp Readout Circuit?
I was analyzing this circuit diagram in a thesis about a capacitive EEG electrode. The author talks about a flaw in the design where there is a "floating analogue input" that is causing the op-amp to ...
5
votes
3answers
1k views
Non-inverting amplifier ; Single supply ; Bipolar input
I am working on the non-inverting amplifier using a single supply, which can amplify bipolar input signal. Non-inverting amplifier is working fine without any issues, only the negative portion of the ...
2
votes
3answers
440 views
How to add a low pass filter to this non-inverting amplifier circuit?
I've come up with this simple circuit as an amplifier before an 8bit ADC which receives audio signals. R2 is actually a variable resistor (pot.) of 100k. The circuit also biases the signal to VCC/2 ...
3
votes
2answers
476 views
Gain of Non-Inverting Amplifier Does Not vary with Resistor Values
I am trying to build a non-inverting amplifier using a LM7171 op amp, and I am implementing it with potentiometers as Rf and R2 so that I can smoothly control the gain of the amplifier (and easily ...
3
votes
1answer
943 views
Why is CMRR effect multiplied by gain in this non inverting op amp configuration?
In this document Vout of a non inverting op amp is given as follows:
But why \$\frac{V_{in}}{CMRR} \$ is also multiplied by the gain?
I would write it as:
\$ V_{out} = \big[1 + \frac{R2}{R1} \big] \...
0
votes
2answers
178 views
Strange behavior in a non-inverting op amp
I've designed a simple non-inverting amplifier to interface a 3.3V MCU and a 5V signal to a motor controller. When I first tested with the MCU and the desired values to the low-pass filter, I noted ...
1
vote
2answers
274 views
What is the difference between these two op-amp circuits?
I don't understand why when we design a proportional amplifier, the feedback has to be negative. When I run the simulation in simulink I get the same result for both circuits.
1
vote
2answers
70 views
Is it possible to suppress oscillation at reactive load (non inverting amp)
I am using a non inverting amp with B class voltage follower to drive a piezoelectric transducer (used as sonar for fish scanning in boats). I am using trains of 20 sinewave pulses (85KHz), like the ...
0
votes
1answer
64 views
Whats the gain of this op amp?
what i did here is take current over the 4.7 kilo ohm and since there are no other voltage input other than the one then shouldn't the Vout be 0.2127 volts? thats not possible for a non-inverting ...
1
vote
2answers
222 views
Why my non-inverted amplifier does not work?
I'm trying to use a TL081, for which I used a DC power supply regulated by MPL1303, to feed the TL081 and a Vin from a DAQ assistant giving an analog signal of 0 to 5 V. I tested the signal from the ...
0
votes
1answer
502 views
Application of offset voltage to non-inverting input of the op amp
When we analize the effects of the offset voltage at the outlet of an amplifier configuration, we consider that this voltage is applied to the non-inverting input. At least it appears so in all the ...
1
vote
2answers
117 views
How do I determine the purpose of this op-amp circuit?
I have this circuit and I was asked to determine V2=f(V1) and V3=f(V2) which I determined below. The next step is to figure out what the purpose of this circuit is but I'm not sure how to do it from ...
0
votes
1answer
692 views
Voltage Amplifier using Op Amp 741 [duplicate]
I am trying to build an amplifier using op amp 741. But I am failing to build it on breadboard.
I am connecting the positive end of a 9 V battery to pin 7 and negative end to pin 4. As per my ...
1
vote
1answer
415 views
Non-inverting op amp problem
I have problem with an lm386 op amp in an non-inverting configuration. For the resistors, I take two equal resistors so i set a gain of 2. When i put a signal of 3.3 volts on the non-inverting pin, i ...
1
vote
1answer
116 views
Fluctuating Non-inverting opamp o/p
In the non-inverting amplifier shown below, when the DAC output (TP1) is held constant at 2.5V (same input code), the OP213 opamp output (TP2) fluctuates between 8.750 and 8.775V i.e., roughly 25mV. ...
-1
votes
1answer
267 views
Non inverting amplifier oscillations [closed]
The point of this circuit is to take a 300 to 400 kHz 5Vpp square wave signal and convert in to a sinewave of the same frequency amplified with a gain of 2.
The filtering before the op amp seems to ...
0
votes
1answer
63 views
Solving for adding a voltage to eliminate the non-ideality of the op-amp
The circuit as shown above.
Conditions known:
The op-amp is nonideal.
Both inputs have current flow, lets say 0.7 \$\mu\$A.
Only \$R_F\$ is known, which is 450 \$k\Omega\$.
Open-loop gain is high.
...
