Questions tagged [rail-to-rail]
The rail-to-rail tag has no usage guidance.
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AD627A replacement options
Trying to compare specifications on them and it isn't clear to me if the AD8223 would be a satisfactory substitute. Looking through the spec sheet and what little I do understand terminology wise; it ...
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123
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Slow slew-rate compared to the datasheet
I'm trying to create a 10 kHz PWM signal through use of op amps. In the output I'm using a TLV272IP op-amp working as a comparator:
Since it has as slew rate of at least 1.8 V/us this should give a ...
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Biasing a DIY current feedback opamp
For a personal project, I'd like to make a discrete current feedback opamp. Here's a simplified schematic:
The question is about how to bias Q3/Q4.
For a nice class-AB output, the sum of both Vbe's ...
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Rail to rail +12/-12 V square wave generation with microcontroller
I need to generate a +/-12 V square wave, +/-0.4 V tolerance is allowed. The purpose is to drive the pilot signal of an electric vehicle level 2 charger, for those curious.
EDIT (clarification): what ...
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Understanding Summation of Currents in a Rail to Rail Differential Stage
In order to understand rail to rail OpAmps I consulted a (german) textbook.
There, I found this principle schematics:
So far I understood, there are two complementary differential input stages (T1, ...
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Tradeoff between (op) amplifier voltage range and offset and settling
I know that an amplifier (let's take an op-amp) can't swing rail-to-rail. The reason has to do with the load device. For example, in a normal common gate/common base amplifier, the load device causes ...
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3
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Unused Opamp Termination: How does it cause increased current consumption?
Usually the following configuration for unused opamps is said to be troublesome, even for rail-to-rail input & output (RRIO) opamps. Nevertheless, it is attractive because it requires no ...
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Does a rail-to-rail input fully-differential amplifier need Common mode feedback at Output nodes?
I am designing an Op-amp with rail-to-rail inputs and the operation being fully differential in nature. I am trying to understand whether I will still need a CMFB (common-mode feedback) circuit to fix ...
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OpAmp/Comparator for AC current detector circuit
I am trying to complete schematic for current detector. This is addition on How to build AC current sensor circuit for ESP-01 GPIO.
By googling and researching I came with following schematic which I ...
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TL072 opamp clipping problem
I'm trying to drive a TPA6120 headphone amplifier with TL072. I use single 24VDC supply with a TLE2426 virtual ground.
The TL072 works well and puts out around 21Vp-p sine wave. But as soon as I ...
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Why is my op amp railing?
So I have a LM358 Dual opamp. I only care about the first op amp, the second I just have set to put out 12V to keep it from floating. The the first is reading in feedback from a 1k potentiometer from ...
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Simulating PMOS differential amplifier in Cadence
I am studying about rail-to-rail opamp design and I am trying to recreate the Itail vs Vgs (in this case input common voltage) curve from the link bellow (pages 5 and 6):
https://mixsignal.files....
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Push pull output stage max output voltage
Spent a day trying to understand the maximum and minimum output voltage of the basic circuits as shown in this figure
The problem is that I have come across different expressions for the output ...
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Is it possible to replace the ref pin of AD620A with a fixed voltage?
I am trying to implement the below circuit (from) without ADuC842, I will use Arduino mega2560 ADC.
the circuit generates -5V to 5V rail to rail voltages for ad620a
and they control ref voltage via ...
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Is exceeding Opamp Common Mode Voltage safe?
I understand that when you exceed an Opamps Common mode voltage limit that the output will no longer be reliable. And that this limit is often a bit less that the supply rails. But would slightly ...
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How can I check in an OpAmp datasheet if the OpAmp is push-pull?
I am looking for an OpAmp which I want to use as voltage follower after a DAC. The OpAmp should be able to pull 3mA. And it should have Rail to Rail input and output.
How can I check in a datasheet ...
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How does a common-emitter rail-to-rail opamp output stage work? Is there a discrete example?
I'm reading an article about how a rail-to-rail opamp works. The materials from Maxim and Analog Device all mentioned that, in a conventional operational amplifier, the output stage, in its essence, ...
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Is it a Rail-To-Rail opamp?
I ordered several LMC6482IN opamp without reading the datasheet details! I want to measure high side current with mA accuracy, for that I need the opamp output to go all the way to ground 0V. in the ...
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196
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High voltage op amp rail generation
I'm using two ADHV4702-1 high voltage op amps for a project. They are configured as a current sink with a class B output amplifier (with some fixes for the crossover distortion). I already have a +/-...
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What is the difference between differential rail-to-rail, push-pull rail-to-rail and rail-to-rail OPAMPs
I'm loking for an rail-to-rail OPAMP to my project. I need a OPAMP that fed by a 12V and a -5V power supplies can generate an output voltage near these values, at least, near the positive 12V, the ...
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How can I determine whether this is a "rail to rail" opamp from its datasheet?
I know that rail to rail means that the opamp output can have a swing upto its power rail voltages.
So for a rail to rail opamp lets say if the supply test condition is +-12V, I would assume that the ...
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Are there any single supply OP amps with negative supply voltage?
I learned that basically the only difference between a "single supply" OP amp and a dual supply one is that the former can drive much closer to the negative supply rail.
Furthermore if I understand ...
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Loud hum and buzz... I think I know why but I don't know how to solve
First, read this other question of mine. I have modified the amplifier, as suggested by τεκ to run on the full rail.
This is the modified circuit.
Notice how the amplifier ground is tied to -5 and ...
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Truncating negative results of Op amp by rail limiting
I have a signal that will swing from -5v to 5v. I am interested in the 0 to 5v part only. I will set a reference voltage and give it and the signal into a comparator. The comparator's rails are 0, and ...
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No amplification with LMV358 compared to LM358 in crude current sensing
I am trying to build a current sensing circuit (two channels), with no requirement of precision (i.e., is current passing over some threshold whatnot). The (somewhat generic) circuit I am implementing ...
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135
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Comparator circuit undesirable fluctuations
I have designed a comparator with hysteresis and rail to rail operation and my output depicted in figure1.The inputs of the comparator is a sine wave signal and a triangular waveform as shown below....
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How do I see if an op-amp is rail to rail using only datasheet?
If I have a data sheet or part of it, how can I see if an op-amp is rail-to-rail using only the numbers?
For example, only using the image below, how can I see if input and/or output is rail-to-rail?
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Rail to rail amplifier analysis problem
Can someone help me to understand what we expected in the output(Voutn,Voutp) of the circuit of figure 1?I have searched for months a lot of books but I can't understand the operation of the rail to ...
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1-5V to 4-20mA voltage drop problem
I'm hoping someone can help me remedy this problem (or at least come up with a temporary solution), as I am a novice in electronic circuits.
The below circuit shows my setup. Vin is my input signal ...
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LMC6062 Jumps too Rail when 1V below
simulate this circuit – Schematic created using CircuitLab
I'm using a precision OP AMP LMC6062AIM as a buffer (Voltage follower). The supply is +5V and GND.
The INPUT is a DC voltage (no ...
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What does "rail to rail output opamp" mean?
Context:
I have a very similar problem to the one exposed here, and in the best rated answer (by Olin Lathrop), he says we need a rail to rail output opamp.
My question:
What is a rail to rail opamp? ...
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How to understand rail to rail input circuit?
I watched an input circuit for ground rail as follows,
Why do I have to place a current source here? If I place a resistor instead, there will still be current flowing in emitter-base direction for ...
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What OP AMP spec should I be checking to assure this behavior
Recently, on the advice of others on another thread, I tried to migrate a dual supply OP amp circuit to single supply version. I needed a quad OP AMP, and the logic was that since my final circuit ...
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