Questions tagged [non-inverting]
The non-inverting tag has no usage guidance.
166
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555 as MOSFET driver always outputs high with input disconnected
I have been using a 555 timer as a MOSFET non-inverting driver for a few months now. It really is a signal amplifier for an Arduino Nano (which outputs 5 V) and it amplifies the signal into the gate ...
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7
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Infinite output impedance in amplifier, instead of 0?
The question asks: "Exercise 14.5 Assume an ideal op amp and use the summing-point constraint to find an expression for the output current io in the circuit of Figure 14.14. Also find the input ...
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How can I find Thévenin equivalent circuit of the NFB op-amp input? [closed]
I need to find the Thévenin equivalent of the right side of the circuit by looking into node E and F. How can I find it?
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Non-inverting amplifier weird Vout values
I am doing a simulation in multisim to simulate an non inverting amplifier, but i have gotten values that is not what intended. From what i know, the gain for non inverting amplifier is Va = 1 + Rf/...
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h-parameter model for non-inverting amplifier
For a standard non-inverting amplifier as below:
With nodal analysis, I got $$\frac {v_o} {v_i}=\frac {R_EZ_o+aZ_iR_E+aZ_iR_f} {R_ER_f + R_EZ_i + R_EZ_o + R_fZ_i + Z_iZ_o + R_EaZ_i}$$
However, with ...
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I would like to know what type of op-amp this circuit is
This circuit is connected to 250V AC power and I would like to calculate the values of the resistor and capacitor, but I don't know which formula to use to calculate it.
I think this circuit is ...
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Non-inverting amplifier with offset
I have a non-inverting amplifier circuit shown in picture. This circuit has an input wave (-/+ 5V) and output needs to be 0 to 3.3V. I'll be using zener diode (LM 385) as my voltage reference. But I ...
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How to calculate the power supply values for an non-inverting Op amp circuit
I'm trying to figure out the power supply values for a non-inverting Op amp circuit. So far I have: input voltage= .03 mV, Gain=11, and output voltage=330mV.
I know my output voltage cannot exceed my ...
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1
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Why Am I Not Getting my Expected Output in this basic Op-Amp Circuit?
I thought that A = 1 + Rf/Ri for an op-amp non-inverting amplifier? With a 1mV input, I'm getting output voltages in the uVs...
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In testing this op-amp, I always get same amplification. Did I break it?
I bought these TL072 (maybe TL072CD) IC amps, for a circuit I was trying to build, but the circuit wasn't working at all so I tried to troubleshoot the amp.
I built a voltage divider ~1/1000 (on the ...
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Difference in inverting and non-inverting integrator
I am trying to simulate the step response of an inverting integrator and a non-inverting integrator.
However, in the inverting integrator's output (blue plot), I see an initial overshoot in the ...
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2
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305
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Opamp-based Schmitt trigger [closed]
I have attached two opamp-based implementations of Schmitt trigger. Output of one will be inverted when compared with the output of the other circuit. Clearly, the difference is in which terminal the ...
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Decrease in bandwidth of inverting opamp
The bandwidth of inverting opamp is lesser than non-inverting opamp. If both configurations have equal closed loop gain and also Gain-Bandwidth product (GBW) for opamp is constant for both cases (...
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Non-inverting NE5532 with 1.56 gain not working
I made 4 preamp's for laptops and cellphones using 2 NE5532 IC's. The expected gain is 1.56 so, I used a 5.6K resistor as the feedback one and a 10K from the inverting input to a 47uF bipolar ...
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Inverting op-amp problem
Down below is an inverting op-amp circuit with a capacitor C connected to the non-inverting input. I have to find the voltage at point A and express it using vin, C and R.
I tried to solve the ...
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How to find driving point impedance of non-inverting op-amp circuit
I have this circuit:
And I am asked to find the driving point impedance.
I know that a driving-point impedance relates the voltage and current at a pair of terminals. The formula for the driving-...
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Transfer function of non-inverting op-amp circuit
I have this circuit:
I am asked to show that the transfer functions of the circuit is:
I know that for non-inverting op-amps:
\$ Z_{in}=\infty \$
\$ Z_{out}=0 \$
\$ H(s)=\frac{V_{out}(s)}{V_{in}(s)} ...
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3
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Bias voltage in non-inverting op-amp topology being pulled down
I decided to quickly put together a circuit today but found an issue that has sometimes happened when making circuits with TL072.
Briefly, the circuit is a non-inverting amp with about 34dB gain in ...
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Single-supply non-inverting op-amp for summing DC voltages at unity gain
Is it possible to use this single supply, non-inverting, summing op-amp configuration to sum multiple arbitrary DC voltages at unity gain?
I've used the inverting summing op-amp config on bipolar ...
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Powering a negative resistance converter with an Arduino power pin
I want to build a negative resistance converter and the only voltage source I have is a 5 V Arduino power pin.
I am afraid the reverse current (Is) flowing through the power pin will destroy my ...
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Is this the correct way of making a non-inverting optocoupler?
Requires to read 24 V input signal, and output to an Arduino as 1, at the same time it lights up the LED indicator. Is this circuit viable?
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I have to find the relationship between Vout and Vin
Can someone use this picture as an example of how to systematically solve/calculate this problem?
My teacher has written terrible, inconsistent notes, and now I'm confused for which formulas to ...
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Non-inverting op-amp
Why is resistor R1 connected to the inverting terminal of the op-amp in a non-inverting op-amp configuration? What will happen if we replace it with a short circuit?
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Why do we need R1 in a non-inverting op-amp?
I am quite new to learning op-amps.
What is the purpose of putting R1 there? Does this have any meaning in the design of a microphone amplifier?
I read about this from another answer, which says that ...
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175
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Why doesn't this op-amp schematic work?
If I use just the first-stage op-amp it works, but the output from the first stage is 2.5 V. If I give it some signal the output will be 2-3 V. In the second stage I use a voltage divider and the ...
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Non-inverting amplifier with stable gain
I'm working with a LM358 op-amp as a non-inverting amplifier to get a 0-24 V output from a 0-5 V input. When the input is 1.5 to 5 V, the gain is 4.8 which is OK (set by resistors), but below 1.5 V ...
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666
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About "Always inverting except when you can't" of OPA
Recently, I read here:
Always inverting except when you can't
Always adopt inverting, the reason for which is that noise can be reduced.
Why? Could anyone explain in detail?
I also have a problem.
...
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Why is my op-amp giving same output for low voltages? [closed]
So I am trying to make analog output 0-10vdc with my esp32 microcontroller.
I have read that esp can give true analog voltage cause it has DAC so my plan is to connect one of esp32 DAC pins to non ...
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Is hysteresis needed for this non-inverting comparator?
I’m trying to figure out if the following comparator circuit (TL331) would be reliable in the following application, or whether I would need to add anything, like hysteresis.
To explain the ...
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Texas Instrument OPA192
I'm examining the datasheet of the OPA192. When the inverting input of op amp tied up the op amp output and if the non-inverting input of op amp had been floating, what would have happened the op amp ...
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How does input resistance cause phase lag in the output in a voltage follower circuit?
I was solving a problem related to voltage follower in Fitzgerald's Basic Electrical Engineering, 5th ed., pages 458-459. The op-amp characteristics are (respectively open loop gain, open loop ...
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Calculating the relationship between Vout and Vin in a non-inverting op-amp
Circuit:
I have to determine the relationship between Vout and Vin. When analyzing the circuit I realized it was quite similar to a non-inverting op-amp circuit. I know from my past homework that I ...
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High output voltage from non-inverting amplifier without input signal
I bought an LM358 amplifier module to boost the input signal of 0-1 Vpp 20 kHz sine signal to 0-3 Vpp 20 kHz sine signal (gain of 3.)
I tested the circuit with the input pin (non-inverting pin) ...
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Thermocouple circuit not outputting expected values
My application requires 11 thermocouples to be sampled and logged. Below is the circuit diagram, containing a differential and common mode filter, non-inverting amplifier (gain 111) and a second order ...
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AD8065 Offset problem
I'm an electronic engineering undergrad and your discussions helped me a lot. As a project, i was instructed to design the front end for a data acquisition system. The specs as below.
Supply +/- 5V ...
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Non-inverting amplifier isn't amplifying my signal
I am using a non inverting amplifier (shown below). For the opamp, I am using TL084, and I am using 12V single supply. I am getting an output of 11.20Vdc even though the input is 1.06V sine wave. I ...
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Why do you suppress the input when finding the output impedance of an opamp circuit?
In most derivations of the output impedance of an (non-ideal) non-inverting opamp circuit, the input terminal is grounded (e.g. page 5/6 here or page 76 here). It also seems to be a common procedure ...
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How to calculate the gain of a non-inverting opamp with a transistor?
I have a question about this circuit. How do i rearrange the formula to calculate the voltage gain of this opamp with a transistor:
I know the formula for the gain of a non-inverting opamp like in ...
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What will be the output of a single supply voltage follower circuit if negative voltage applied to the non-inverting input?
I am providing 1.8 V as supply in a single supply voltage follower circuit. Now my concern is if I put negative voltage (Range -1.3 V to -500 mV) in the non-inverting pin, what will the output from ...
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Amplifier clipping output signal [closed]
I constructed a noninverting amplifier with a sine wave input (0.5 Vpp) and observed an output signal that was clipped equally in both the positive and negative regions, to about 2.5 Vpp. I tried to ...
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How does this op-amp config work as a voltage follower?
I've checked a couple of books and the internet, but every source just tells me it's a voltage follower, and not why. Without any resistors, I'm having trouble applying the 2 golden rules of opamps (...
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Range of feedback resistor value in non-inverting op amp
Is there any limitation for the range of the feedback resistor in a non-inverting circuit? What happens if I choose feedback resistor very high or very low? What is wrong with choosing a 10M ohm ...
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How to make my signal square without using two MOSFETs (and inverting it twice?)
I am trying to extend an existing solution to decode a specific signal (solved here for 1200bps speed: http://hallard.me/demystifier-la-teleinfo/ - article in french.)
A 9600bps signal comes from a ...
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Design methodology for non-inverting summing op-amp
I'm trying to design an op-amp circuit to sum up four voltages by using a non-inverting summing configuration. You can see it in the circuit below, though for illustration's sake, the resistor values ...
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596
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Preventing op-amp outputs from affecting one another
I built this op-amp circuit that takes in 4 inputs and outputs 3 sums by using op-amp adder and difference circuits to achieve a gain of 2x. In a simplified circuit, I boiled it down to the bare op-...
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TL071H unity gain buffer output voltage drops to zero when input near to zero
When the input voltage is smaller than 300 mV, the output voltage drops to almost zero.
When it is above 300mV, the output follows the input.
Why? If there is any discrepancy between input and output, ...
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Amplify DC signal: how to deal with real life problem ==> output is close to Vs when input signal too small OK otherwise
Hi I believe this problem must be classical and well known but I cannot find a place where it is specifically discussed:
I have build a simple non inverting 2X amplifier following exactly the ...
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Why are low values of resistor in non-inverting configuration of opamp causing gain peaking?
I am trying to simulate frequency response of TLV07 in non-inverting configuration for gain 10 as shown below:
The frequency response shows peaking as shown below:
It is worse for smaller values of ...
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Why does current noise flow through the parallel combination of R1 and RF in a non-inverting opamp?
I am following this reference for noise calculations of a non-inverting op-amp.
I am not able to understand why the equivalent resistor is the parallel combination of R1 and RF as shown below:
I ...
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Why is the op-amp not able to amplify this voltage? It's a straight-forward non-inverting configuration with ideal op-amps(LTSpice simulations)
So I have the following configuration (pretty straight forward right?)
But following are the waveforms of V_induced(the voltage to be amplified) and V_induced_amplified. As you can see, the voltage ...