A comparator compares two voltages or currents and switches an output to indicate which is larger.

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Conditional Voltage output

I apologize if this is extremely simple, but I am trying to design this: I input 2 voltages, one is 12 V and the other is on the order of .5V. I want to know if there is something I can set up that ...
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32 views

Output State of comparator circuit for AC signal when open?

I am trying to design a circuit which would interface AC signals from pick-up coils. Below is the circuit. R4, R3 are for DC bias, and R2 is for feeding that bias to inverting input of the OP amp. ...
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47 views

How can i make my o/p equal to 0 and 5?

I have a comparator circuit that is supposed to output logic 0 or 5 but am getting 1.35V and 4.8V there's no problem with the high my problem is with the low how can i get it to 0 and 5? I am using a ...
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Design a 3 bit comparator [on hold]

Iterative designs for comparators are quite successful which makes use of 1-bit comparator cells to make n-bit comparator. My question is how can we design a 3-bit comparator with a 2-bit and one ...
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43 views

Does Analog Comparator mean Voltage Comparator?

I was asked to define what an Analog Comparator was. After doing research, it seems to me that Analog Comparator is the same as a Voltage Comparator. Is this true?
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69 views

Pull-up resistor causing unintentional voltage divider?

I'm trying to use the output of a comparator as the input of a schmitt trigger built with positive feedback on another comparator. Both have open collector outputs. When the two are not connected, ...
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38 views

Schmitt trigger application

I have a sine input signal in range from -0.2V to +3.3V. I would like to detect zero crossing with comparator in Schmitt trigger wiring with hysteresis between -0.1 and +0.1V. Is this circuit possible ...
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55 views

Two different voltage input to be monitored by microcontroller

I just wanted to make a detailed circuit design that I can use in my project. a design that can supplement on the OR gate Given the two different voltage input, I need an output of a voltage around ...
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28 views

Comparator with latch as trigger

I was hoping to use a Linear Comparator with a latch such as LT1016 as a trigger for the Register output clock for a 74HC590. The 74HC590 is going to be cascaded with it's RCO going to several more ...
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19 views

Propagation Delay Jitter

I am designing a system in which propagation delay will be very critical. I will most likely use a comparator and an analog switch or just an analog switch alone. If the propagation delay is ...
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95 views

LM358 as a comparator output problem

I've got an LM358 based ground fault detector circuit that I've recently revised, and the revision broke it, so far as I can tell. To make a long story short(er), what it amounts to is using one of ...
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80 views

LM311 Circuit only works when probe is attached

I'm trying to put together a circuit that takes a signal from a sensor, cuts out the negative side, compares it to a reference voltage and outputs a digital 1 when above the reference voltage. That ...
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61 views

Power Gating a Comparator

I am using a comparator (TS3021) as a zero crossing detector (ZCD). The ZCD toggles its output based on the zero crossings of a sine wave generated across a transformer coil. One end of the coil is ...
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64 views

Is this something a P.L.C. would be able to do?

I wish to replace the zener diodes with a programmable chip, so that I can program the chip to do exactly what the zener diodes do in this circuit. This will then make the circuit universal to all my ...
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56 views

Measure Voltage (Divide) on a current source

I need to use a constant current source 20mA, the current flows through multiple diodes and resistors which are in series. The resistor value can vary from 0 to 1.6k and also a possibility of Open. ...
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95 views

555 Input Impedance

I'm building an audio circuit and need a comparator. I've explored using an op amp for this purpose but my TL072 doesn't seem to have a high enough slew rate which resulted in latency. Instead, I've ...
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38 views

A question on transforming a non-inverting comparator to an inverting one?

Here is the schematics for the question: I was using the LM311 as a non-inverting comparator without problem. It works fine and here is the output below: But if I use it as an inverting ...
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31 views

Delay ERROR - RC Circuit

I have designed this circuit to measure the current on the load and the comparator trips when the current of 1.2 A exceeds for 2ms.This works fine with simulation.When I build this circuit,my circuit ...
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53 views

Comparator and 7 segment display

I am trying to make a 7 segment display that displays the symbol <, > or = depending if a > b or a=b or a < b by using the output of a comparator(7 outputs from the comparator according to the ...
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108 views

Comparator Latch circuit

I need a VERY simple latching circuit using comparator that will simply be off until a signal hits it (can be either + or -, I have no preference) and the circuit will remain on until I reset it.
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69 views

Low level sine to pulse converter with sharp rising-edges

I have two circuit simulations: Circuit1 and Circuit2 which are shown in above schematics. For the sake of simplicity I drew them in the same schematics. They share the same 12V voltage source and ...
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2answers
51 views

High side current indicator/

simulate this circuit – Schematic created using CircuitLab Hi! I am in need to make a high-side current monitor for detecting whether load (R1) is present or not. As currents running ...
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2answers
89 views

Output current sourced/sunk by comparator

I am using the LM139 comparator chip. Now, I understand that the output of the comparators,or for that matter op amps are open drain/collector. SO they can only sink current and not source it per se. ...
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57 views

inverting comp behaving strange

I am using an LT1716 comparator in the inverting mode. So, I am simulating it in LTSpice. I understand that the Vout is Vcc when Vin,at the inv terminal is less than Vref at the non inv terminal and ...
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64 views

How to detect end of Capacitor Pre-charge

A common problem with batteries and loads connected to them is that the load often has substantial capacitors which needs managing . When the battery is connected to the load by closing a ...
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83 views

How to tell when an LM334 is limiting the current?

I have an LM334 based constant current source configured to supply a max of 1 mA. The load has a variable impedance. My goal is to make an alarm of sorts when that impedance exceeds a threshold, and ...
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166 views

Why add resistor on comparator input?

I'm studying the schematic for the constant current/constant voltage (CC/CV) indicator on an Agilent E3610A: My question is: What purpose is served by the 10kΩ resistor (R26, R16) on the ...
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35 views

Comparator power dissipation

I want to calculate the LM339 comparator power efficiency, so I thought the best way is to calculate the output RMS power and the Power dissipation and the quiescent(DC) power then will get the input ...
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52 views

Comparator reference noise

In the attached circuit, with input of 30mV at 40kHz, the reference DC voltage at pin 2 of the comparator exhibits noise at the same frequency as the input. At low input amplitude (4mV p-p) the noise ...
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77 views

How to prevent internal MOSFET from being precgharged?

For MOSFET circuits: simulate this circuit – Schematic created using CircuitLab Say, how do we make sure that the gates M3, M4 are never pre-charged, so that they will always produce the ...
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80 views

LM339 basic operation

simulate this circuit – Schematic created using CircuitLab What voltage needs to be applied at \$V_{\text{in}}\$ for the LED to turn on? My answer: \$V_{\text{in}} > 9\text{V}\$ Is ...
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119 views

Detecting a coil is fully energized

I'm working on customized ignition system and want to implement the final stage as robust as possible. The ECU (Engine Control Unit) provides TTL level control signal to drive ignition system. The ...
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1answer
78 views

over voltage detection using comparator

I need to design a over voltage protection circuit. I intend to use a comparator for the said circuit. The reference will be from a standard voltage ref source. While the voltage at the non-inverting ...
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28 views

Question about comparator MAX912 latch enable

http://www.hep.uiuc.edu/cleo/trig3/boards/tile/vme021d_data_sheets/max912.pdf I am using this MAX912 as comparator. There is a latch enable in this circuit which according to the datasheet, output is ...
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62 views

Transistor on when comparator is low

Just trying to switch a relay when a comparator goes high with a transistor but the comparator outputs 1.3v when 'low' which is enough to set the transistor. Using a 741 opamp as the comparator with ...
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37 views

Unipolar op amps

Ex : My question is since it's a single supply op amp, does this mean that we can't generate negative voltage so the transfer function would bottom at 0?
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202 views

Open collector outputs with logic gates causing infinite loop scenario

About my project: I am working on a project that involves controlling several LEDs with two Intel Edison microcontrollers and a comparator circuit. There are five LEDs total controlled by four ...
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197 views

Window comparator using LM339 - invert output

I'm using the LM339 for an application with different voltage ranges. I am using the window comparator circuit since I want to test a specific range (4 - 8V). The circuit shown below actually ...
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71 views

How to use a voltage comparator?

I'm quite new to electronics and I'm working on a simple circuit to make an LED light up when the voltage source reaches or exceeds 13.0V. I setup a voltage divider and 7805 on my breadboard and both ...
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93 views

Newbie pinout questions for LM360N

For my first project, I'm trying to make an LED light up when the voltage from a variable source reaches a certain point (13V in my exiting circuit). To do this, I'm going to take the output from a ...
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98 views

voltage comparator always on

I'm using a LM339 voltage comparator by supplying it 5V, with a reference voltage of 1V. I have a 3K pull up resistor on the output to 5V. For some reason, the output voltage is always 2V. It ...
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63 views

Voltage comparator with single rail op amp

I'm planning on setting up a voltage comparator with a single rail op amp and was wondering if I still need to attach a diode to the output because it is single rail and not dual. I would think that ...
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Preamplifier before latch stage in comparator circuit

Adding preamplifier based on simple inverter before latch stage can improve performance of comparator by decreasing offset voltage. Can anybody explain me how it works? Best Regards
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126 views

Role of Resistor at the output of a comparator

What is the role of R1 at the output of this comparator? simulate this circuit – Schematic created using CircuitLab
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128 views

Voltage divider not making any sense

I have been searching like a maniac for as much info as possible before placing question here, obviously i failed... The question is about voltage divider, i have an external source that gives me ...
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50 views

battery overdischage oscillation protection

I previously asked asked an advice on power control of battery operated system. The problem was to cutoff the battery when low to avoid overdisharge. I have built the device according to Olin ...
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74 views

lm324 if i feed it with Vcc but not grounded it,what the value isee on GND pin?

I have lm324 in my circuit and I connected Vcc pin To 5V, but GND pin is not connected (float), so What the value I see on GND pin ?
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Did my comparator break?

I have two inputs for my LM393P comparator (https://www.rcscomponents.kiev.ua/datasheets/texas_instruments-lm393p-datasheet.pdf). I have checked these two inputs with the analog inputs with my Arduino ...
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92 views

Current Sense Amplifier and Voltage Comparator in Same Pacakge [closed]

I am in need of sensing the current in a circuit and cutting off power when current exceeds a threshold which should be about 2A. It seems that everything I've read recommends using separate "current ...
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54 views

Need additional capacitor for comparator?

I am designing a circuit for interfacing the frequency input signal. I used simple Op amp inverting comparator with hysteresis, as below The op amp is single powered by GND and 5V. Otherthan ...