Questions tagged [comparator]
A comparator compares two voltages or currents and switches an output to indicate which is larger.
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Applications for Comparators Stable in Linear Region
These two comparators here MAX913 and MAX9013 are comparators that do not contain hysteresis. They are advertised to remain stable in the linear region and not exhibit instability for slow moving ...
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Problems Comparator II of this CD4046 for LTspice
I downloaded a CD4046B model from user ale_t, which can be found here:
https://www.electro-tech-online.com/threads/new-spice-model-for-cd4046b-phase-locked-loop-ic.149093/
However, the Phase ...
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Can't get output voltage out of LT1011 (LTSpice)
How come I can't get any voltage out of this op amp ? (I have to use that one, can't change it)
THe green signal is the input, the blue one is the output.
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Constant temperature operation of microheater
I have been trying to make a constant temperature control for microheaters based on this wheatstone bridge circuit, using a trim pot to set the temperature setpoint. The purpose is to keep the heater ...
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Square wave (+-15V) to positive DC
How can I convert a square wave signal from -15V to 15V to a positive DC signal?
Here are the details of my problem:
I'm trying to build a duty cycle for a buck converter in the following way: I want ...
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What should be done with unused input of an LM339 and LM358? [duplicate]
I am designing a circuit using an LM339 and an LM358, and I am not using all of the contained comparators or op-amps. I searched through the datasheets, and they did not explicitly state what should ...
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Comparators that can drive large capacitive loads
I quote from Allen and Holberg, 3e, Pg 468:
If a comparator has a large capacitive load, the chances are that it is slew rate limited. Under these conditions, we will show several methods capable of ...
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Can I use one voltage divider for multiple voltage comparators?
I have a circuit that uses multiple comparators, that are comparing the same threshold.
Could I use just one voltage divider for all of the comparators, or if I need a sperate voltage divider for each ...
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Something wrong with a circuit designed
This is a circuit that we designed at AllAboutCircuits to control a solenoid valve.
The circuit tries to leave the solenoid valve deactivated if the PT100 is submerged in nitrogen and to activate when ...
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LM339 comparator not working properly in the defined window
I have designed a circuit that uses an LM2901 comparator which is used for a window in which I should get a signal. I have set two limits for the comparator: 7.7 to 8.8 V for the lower limit, and 11.3 ...
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Need help with op-amp comparator circuit
I have two op-amps connected in series:
The first op-amp only acts as a voltage follower. It is connected to the voltage divider resistors and outputs V/2.
The second op-amp is acting as an inverting ...
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Connections of Voltage Comparator Circuit with LM2903
I am planning to use the LM2903 and a P channel MOSFET to prevent discharging of a LiPo battery below 3.3V.
Here is my current schematic, where 3V3OUT is the output from 3.3V buck boost converter, ...
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Help cleaning up square wave pulse signal
I'm quite new to electronics in general.
My current circuit setup consists of an incoming sine wave. I use a comparator chip to compare this sin wave to a threshold which results in a square wave ...
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Designing a digital display [duplicate]
I was working on a design question (this is not homework, just personal practice). So I have a temperature sensor with a non-linear response, and ideally I would like to design a digital display ...
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Choosing between an op-amp and a comparator
I am a YouTube educated, complete newbie with three questions regarding my design (see the schematic). Because I'm self-taught, some of my terminology may be non standard.
This is a circuit powered by ...
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Comparing two variable voltages with minimal power consumption
I'm trying to design a circuit that compares two variable voltages V1 and V2 and fires an interrupt to an MCU when V2 is greater than V1 and at the same time V1 must be at least 4.4 V. The range of V1 ...
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Schmitt trigger using JFET
I want to make a Schmitt trigger using a JFET instead of a bipolar transistor. I started by trying to understand how this circuit worked using a BJT and then moved on to try and replace them with ...
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Comparator with linear output to equalize inputs [closed]
I am a ME dabbling in some EE projects so forgive me if this sounds clueless! I am developing a current feedback system for a power supply.
I am looking for an analog device that will adjust the ...
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Guidance needed on PWM brushed DC motor driver circuit
First time posting here, so please bear with me !
I want to mount a brushed DC motor on a bike and drive it with PWM.
I know I could directly use a PWM generator IC, a 555 timer, use an Arduino or use ...
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Why aren't my LEDs turning on while using Proteus?
I'm trying to simulate an audio vumeter, using an audio amplifier built with a LM386. However, when I connect the output of the signal to the input of one of the opamps (I'm using LM358), the outputs ...
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Comparator configuration that doesn't provide output change
I've this two configuration of a comparator in falstad:
Looking at plot I have a voltage difference between + and - , but I don't have an output change. I've tried to find out why, especially on ...
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Sequential LED turn signal + pulse sequence
I'm trying to build an LED circuit what outputs 2 different sequential patterns. The first patterns is a 7 LED sequential turn signal using the ne555 timer module. I'm trying to make the LEDs ...
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Low power reset pulse about every week
I have a microcontroller in deep sleep and I want to send it a reset pulse every week to do some periodic task.
I have a power budget of about 1uA.
I’m thinking of using a circuit like this but ...
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triangular generator showing weird behavior when reducing the capacitance
I made this triangular wave generator, the left op-amp is an integrator and the right one a non-inverting comparator with hysteris.
I require a 1khz signal with Vpp=5V and average value 2.5V. My ...
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Parasitic capacitance of high-speed comparator
I simulated an LM119 high-speed comparator and built one on a breadboard.
May I ask how to increase the frequency of the square wave produced by adjusting the resistor's values instead of reducing the ...
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2
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Simple op-amp comparator circuit not behaving as expected
I've been attempting to design a circuit that will observe a connector and light an LED when there is a sensor connected to the connector. The LED will be off when the connector is left open.
The ...
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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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How to use the "ground-referenced" comparator on this microcontroller?
I chose to use an STM8L101F3P6 low power microcontroller for a sensor node. This microcontroller, however, lacks an ADC and instead implements 2 comparator units with a block diagram presented on its ...
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Simplest way to compare two voltages and output the one that last changed (by a small %)
I am working on an installation in a living space where there will be two wall mounted volume controls. Whichever volume control is last operated, should be the one that sets the volume of the audio.
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Comparator output problem for zero cross detection
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Could anyone give me advice on this zero cross detection circuit I'm working on to allow for phase angle detection?
Just to add I'm only a student so I'm very much still learning. My background is ...
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Comparator circuit analysis
comparators are used to measure whether a particular voltage is above or below reference voltage. It makes sense for the led to turn on when input voltage (v+ > v-) and turn off for input voltage ( ...
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Which specification of an op-amp will cause output waveform at ramp down
I would like to select a new op-amp replacing the old one (OPA171) for some reasons and then the TLV3701 was chosen for a new design. I simulated both in Pspice and found the output waveform of the ...
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Why use only one comparator for back-EMF (ESC build)
I’m working on an esc project. I’ve got the motor spinning by just using a timer to switch the phases on and off. Now I’m trying to include circuitry for BEMF reading. I was watching a video from ...
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Single-cell lithium battery powered comparator circuit with hysteresis
I recently was reviewing a circuit I made and began to question its feasibility. The circuit cuts off a battery's connection to a load after the voltage has fallen below a certain threshold.
To ...
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Propagation delay vs max flipping frequency of a comparator
Almost all datasheets of comparators will show their propagation delay, which means the time it takes for the input pin's change to be reflected by the output.
However, if we have a high-frequency ...
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Battery with low-voltage cut-off comparator circuit
I have a simple comparator circuit I was planning to use for a 2-cell Li battery. I'd like to cut the voltage off at around 2·2.8 V = 5.6 V.
To accomplish this I have the circuit below, but just a ...
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Flash-ADC: sampling or integrating?
My understanding of a flash-ADC is that it simultaneously compares an input voltage to a ladder of reference voltages using multiple voltage comparators. When used in a fast digitizer, the comparison ...
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Using ATmega AVR8 comparator as an earth leakage circuit breaker to detect up to 70 V leakages
I've created aluminum fixtures for VFD tubes, which means that many small wires running voltages up to 70 V are inside these metal tubes. I can connect these metal fixtures to GND, but maybe a better ...
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Calculating hysteresis with an open drain comparator
I have a circuit as follows which will compare an input voltage to a 2.5 V (actually 2.3 V) reference. In one of the documents, it mentions that the feedback resistor must be 100 × Rpullup. If my ...
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555 TIMER ic: TI Datasheet: not able to understand these lines
I have studying the 555 timer IC by experimenting and working out the internals. I now have a good understanding, and hence visited the application note in the datasheet, only to find this statement.
...
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Dual Comparator Circuit
I've received a board with the following circuit:
simulate this circuit – Schematic created using CircuitLab
The INPUT is a digital signal coming from a MCU, with HIGH value being 3.3V. Based ...
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Safety circuit to control maximum voltage
I am looking for a way to control an analog signal from another system that changes between 0-1 V.
The user could define the maximum voltage value, for example 0.793 V (the analog signal has ...
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Op-amp voltage comparator
I am using an op-amp (LF353P) for my voltage comparator circuit. The supply voltage for the op-amp is +12 V and -12 V. The input voltage for the inverting pin (Vref) is 1.1 V. The input voltage for ...
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Does this circuit exist? Frequency comparator of sorts
I need a circuit that compares two periodic pulse signals and outputs a low or high when the frequency of one is higher than the other.
The two input signals are coming from CMOS 74HC devices. The ...
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Input voltage shift of a comparator
I am working on an envelope detector circuit. The circuit diagram is as shown here:
The output of the envelope detector (RC) is connected to the inverting input of the comparator with hysteresis which ...
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STM32 Interrupt large latency
I am writing an STM32F303 application to digitize pulse signal amplitudes. There will be a peak detector, that can be reset by the uC pin, so I'm not expecting the uC to instantly digitize as soon as ...
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Oscillating comparator in a discrete DC-DC converter
I am making a boost converter for a Geiger counter, based on the STM8L152 MCU. Here's the circuit:
The circuit reaches the correct voltage and consumes only 8 μA, however, there are parasitic ...
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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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What's the difference between dynamic comparator and improved latch-type sense amplifier in a flash ADC?
I know about flash ADCs that use comparators or sense amplifiers as in the pictures.
What's the difference here? They seem different, as they have some different type of sensing sequence, and it looks ...
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Line level voltages clip indicator
I'd like to implement the clip LED indicator for the SEND outputs of my module. This schematic from «Elliott Sound Products» seems to be sufficient.
What is the PRO line levels voltages that I have to ...
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