Questions tagged [hysteresis]
The hysteresis tag has no usage guidance.
99
questions
1
vote
1
answer
50
views
Implementing UVLO on battery charging and boost controller ICs
I recently bought a Adafruit PowerBoost 1000 Charger and found out it does not have 32.V UVLO to protect the battery.
The boost controller IC has low voltage sense (LBO goes low when undervoltage) ...
0
votes
1
answer
78
views
How to understand the next values of a comparator inverting with hysteresis (Schmitt Trigger)?
I have my test graded and I'm curious about a question, since I think it's badly graded and I may need to request a revision.
I have been told there is a comparator inverter with hysteresis so \$|V_{...
2
votes
2
answers
103
views
Trying to implement a comparator with hysteresis
So here's the circuit:
I need to design the comparator with hysteresis.
So i saw this video:
I was thinking of doing the same on my circuit.
Vin will be connected to R1 and RNTC where it will form a ...
0
votes
1
answer
53
views
Improve conceptual intervalometer for rotating potted plants
I'm trying to avoid having my plants tilting or otherwise looking bad after only getting sunlight from one direction. To solve it, I want to make the pots rotate.
I'm trying to design a cheap, stand ...
1
vote
3
answers
118
views
Inverting Schmitt trigger design with subtle changes to the hysteresis loop and tripping voltages
Currently, I'm trying to analyze a Schmitt trigger circuit using the 741 IC op-amp, and how it overcomes the problems faced by an open loop comparator circuit.
This is a typical positive feedback ...
0
votes
0
answers
90
views
Power MUX Circuit with 5V & 3.3V Regulation + Reverse Polarity Using LM358 - Questions & Concerns
I'm working on a circuit that can be powered via USB or via header pins.
The goals are:
The MUX will determine, and prioritize, the higher voltage supply.
The MUX will provide reverse polarity and ...
0
votes
2
answers
142
views
How to scale (0-7V, 15-18V) to (0V, 3.3V) for OTGW project
Introduction
There is an open source project for implementation of Opentherm protocol which defines the master and slave circuit for digital communication according to the protocol specification. ...
1
vote
1
answer
139
views
Does the thermostat cause arcing?
I am planning use to resettable thermostat switch in my circuit. I will use it to turn off the optocoupler input. With 5 volt, current is 5-10 mA in optocoupler LED. But I'm worried that an electric ...
3
votes
1
answer
166
views
Why does this hysteresis curve approach saturation so immediately?
I am trying to find out the hysteresis curve of a transformer iron core. I use an LM741 for the op-amp integrator.
As I increase my 50Hz input voltage, I observe that Vin (value on the x-axis) does ...
0
votes
1
answer
58
views
Hysteresis curve's Y axis seems to be primarily measuring the DC dual power supply of the opamp integrator
I am trying to find the hysteresis curve of a transformer's iron core.
The curve looks good, but I do have a doubt:
The LM741 op-amp integrates the output voltage signal from the transformer's ...
8
votes
1
answer
150
views
Why is the saturation in the opposite direction different from the saturation?
I am trying to obtain the hysteresis curve of a iron core transformer.
To integrate the voltage output from the secondary coil, I used an LM741 opamp, 10k ohm resistor, 0.1uF capacitor, and 1M ...
3
votes
1
answer
216
views
Hysteresis curve does not look like what is expected on the oscilloscope
update: Based one the comment from @Andy aka, I tried to obtain the curve without using the integrator. It does give me a better looking graph.
Afterward, I switched the power supply to another larger ...
0
votes
1
answer
76
views
How to set up an oscilloscope with a 10000 turns 0.05A transformer and an AC power supply, in order to generate a hysteresis curve of the transformer?
I am a high school student investigating how varying the current output affects the shape of the hysteresis curve of a transformer.
To measure the hysteresis curve of the transformer's core, I tried ...
0
votes
0
answers
39
views
What do fixed values for the coercivity and remanence of magnetic materials really mean?
I've recently found a table in a book that lists values for the coercivity and remanence of some magnetic materials, one value per material. As far as my understanding goes, the shape of a material's ...
1
vote
0
answers
44
views
Why is B-H curve preferred to B-B_vac curve?
Can someone please tell me why we use H in the \$B-H\$ curve?
I initially thought
\$H\$ was the field strength of the field developed in a vacuum when a current is passed through a coil (placed in ...
4
votes
1
answer
233
views
Is magnetic hysteresis present even with a DC bias?
Consider the following circuit:
With Vin(t) = A sin(ωt) for some given frequency ω.
The relationship between Vin and Vout is certainly non-linear, because of the effect of hysteresis in L's magnetic ...
4
votes
2
answers
212
views
I am facing a problem while designing a Schmitt trigger circuit
I am applying a Schmitt-trigger to the waveform given in the figure below.
.
This is a 3.5 volt signal and I want to perform thresholding so I use 1.58 volts as upper threshold and 1.17 volts as lower ...
1
vote
1
answer
52
views
Weird hysteresis behavior
I am an EE student and recently we worked with Schmitt triggers, positive feedback loops, and hysteresis. I was curious and hooked up an mcp601 without a feedback loop as such:
In the above schematic ...
2
votes
2
answers
348
views
Hysteresis on LTspice with thermistor
I'm trying to simulate an hysteresis on LTspice. The goal is just to see how evolve the output voltage in function of the value of the thermistor. For this, I have done a simulation with several steps....
0
votes
1
answer
122
views
Op-Amp dynamic hysteresis
What is dynamic hysteresis in Op-Amp?
I read section 4.3 of the this App Note and was not clear.
Can someone explain me why this is happening?
0
votes
5
answers
961
views
Can we declare Schmitt triggers to have memory? Can we call their output levels states? [closed]
Are Schmitt triggers able to be declared as having memory? Can we call their output
levels states?
0
votes
2
answers
70
views
How is the effective parallel resistance of this resistor network determined?
I have this circuit:
The effective resistance at the reference node of D4801 is given as
Rb = R4802||(R4805+(R4807||(R4806+R4808+44KOhm))) = 9.129KOhm
I am not able to understand how this formula is ...
0
votes
1
answer
29
views
MAX882 battery protection
I am thinking of using the MAX882 IC to protect my battery from overdischarging. What I could not understand from the datasheet I provided is that, if I use the STBY pin to set a threshold for my ...
2
votes
1
answer
424
views
Comparator hysteresis input signal filter
I need to heavily low pass filter an input to a hysteresis comparator, but due to the fact that R1 is one of the components setting the hysteresis, I can't add additional RC-circuits in series with it....
0
votes
2
answers
65
views
How to define the hysteresis of the buck-boost operation mode?
In the buck-boost (transition) operation mode of a four switch cascaded buck boost converter, there is supposed to be a hysteresis to prevent bouncing. How do we define the hysteresis in this case as ...
0
votes
2
answers
322
views
RS485 Input Hysteresis
What is the meaning of Input Hysteresis in the context of a RS485 transceiver?
Thanks
0
votes
1
answer
236
views
Comparator have hysteresis with pull-up resistor?
I didn't add any hysteresis to below circuit but there's ~500 mV delay between output going high and low, output goes high at 7.5 V but goes low at 7 V:
simulate this circuit – Schematic ...
1
vote
1
answer
54
views
resistor selection for TPS3700DDCR undervoltage circuit
I am designing an undervoltage circuit for a lipo battery project. I found this tutorial here which lead me to the TPS3700. I am wanting the undervoltage condition to be 3 volts. The part that I am ...
2
votes
0
answers
42
views
Does a pinch imply the presence of memcomponents?
There is a famous article by Chua "If it's pinched it's a memristor", where he defines a memristor as having a "[...] pinched hysteresis loop in the voltage–current plane when driven by ...
1
vote
0
answers
200
views
Magnetic hysteresis BH curve to compare "Fe-Ni" "Fe-Si"
I am compiling some training material and would like to include a graph to indicate the different characteristics of silicon steel "Fe-Si" and mumetal "Fe-Ni". The best curve I could find in SI units ...
0
votes
2
answers
547
views
Schmitt Trigger design
Vcc=5V, Vin= a noisy input voltag
I'm designing a non-inverting schmitt trigger using voltage divider. As shown from the image, I designed it on LTSpice and I got the desired results but from the ...
2
votes
0
answers
237
views
What's wrong with my comparator
I'm trying to set up a comparator that goes high when the input is above 0V and goes low when the input is below -5V. I've used the datasheet equations to calculate the resistors for a non-inverting ...
0
votes
2
answers
106
views
Noisy output from opamp comparator
I built the following circuit to filter noisy pulses from a inductive tachometer pickup. The first opamp (U4D) acts as a peak detector. The second opamp (U4C) is a comparator which uses the output ...
0
votes
1
answer
102
views
Comparator with Internal Hysteresis
I need clarification regarding comparators with internal Hysteresis.
I have a comparator with internal Hysteresis “X” mv and I am using external feedback resistors to create a hysteresis of “Y” mv.
...
0
votes
1
answer
39
views
What is the cause of the error/unexpected outcome in water temperature control heating system circuit?
Here is the circuit with components I built as shown over here. The title of the circuit is water temperature controlled system. The function of this system is to control the heating while sensing the ...
0
votes
2
answers
55
views
Calculating core length and question regarding B-H curve
I understand the problem and all (or so I thought), but my answer was way off. Looking at the solution, I realized that I calculated the core length wrong.
I don't understand how though. Shouldn't \$...
0
votes
1
answer
58
views
Interpretation of the graph of excitation current for magnetic circuit
(From Electric Machinery, Fitzgerald)
Why does the current waveform here have such a sharp peak like that?
1
vote
1
answer
84
views
Op Amp Output Voltage with Hysteresis
so I have to design a circuit which lights up 2 LEDs depending on the output voltage of the Non-Inverting Amplifier. I haven't connected the LEDs in the circuit below because it's not part of the ...
2
votes
3
answers
1k
views
Output of LM393 won't swing LOW unless it is pulled up with a LED
I built the following circuit using an LM393 as part of a noise gate for audio applications. It's a voltage comparator with hysteresis.
I originally connected a 10 kΩ pull-up resistor and then ...
0
votes
3
answers
543
views
Schmitt triggers hysteresis symbols
So we're studying Schmitt triggers at university and we got these representations. Searched them on google for more info and got other representations. Now I'm confused. Can anyone help me with some ...
2
votes
0
answers
150
views
What is a suitable hysteresis value and averaging period for a residential thermostat?
I've built a microcontroller based thermostat that I am using to control my home HVAC system. The actual programming and physical assembly has been straightforward. I'm using DS18B20 sensors, so I ...
0
votes
0
answers
74
views
Solar power pump - Design critique and help
Okay so, I have a design that 'works' on the breadboard. But I feel like it could use some improvement. Here is my current design:
simulate this circuit – Schematic created using CircuitLab
...
0
votes
2
answers
153
views
Hysterisis - How do you choose a good value for R3?
simulate this circuit – Schematic created using CircuitLab
Above is the basic schematic for a comparator with hysteresis. Determining the values of R1 and R2 is fairly straight forward. They ...
3
votes
2
answers
3k
views
What is the common name for this seal-in relay?
I'm trying to build a hysteresis water pump system with 2 water level switches. Please see the diagram and explanation of this setup I've taken off the web:
The first switch (L) is set at the minimum ...
3
votes
1
answer
470
views
Questions regarding eliminating hysteresis in ac dimmer
In the following circuit it says:
“This hysteresis effect can be eliminated however, using the circuit from a detailed application note from Littelfuse shown in Fig. 6.4.4. Here the capacitor C1 is ...
0
votes
2
answers
2k
views
Calculating resistor values for a Schmitt Trigger and LDR circuit
I am trying to make a light sensing circuit which has hysteresis.
I want an op-amp (LM358) to output logic 1 (12v) when the light level rises above 250 lux, and output logic 0 (0v) when the light ...
0
votes
1
answer
195
views
Magnetic material demagnetization through Curie temperature
It is known that some materials lose their permanent magnetic properties when they are heated above certain temperature known as Curie temperature or Curie point. As those materials are cooled down to ...
1
vote
5
answers
721
views
Schmitt Trigger hysteresis
I am studying comparators and Schmitt triggers. And I did not find anywhere how to choose the value of hysteresis. I understand its purpose and I know how to calculate it. But what value is needed for ...
0
votes
4
answers
316
views
How can I modify this circuit for some hysteresis and better design?
I need to make a circuit even when the push button pushed and released very fast, the final output will stay ON at 12 V for roughly a second. 10% accuracy for the timing is fine. An LED will indicate ...
0
votes
1
answer
80
views
-Ve feedback comparator and its threshold values?
I was trying to analyse and understand the following circuit.
My intention was to calculate the hysteresis of the comparator.
Circuit working: For both compartor input, there will be voltage inputs ...