Questions tagged [resistors]
A resistor obeys Ohm's law (\$\small V=I\cdot R\$); the current through it is equal to the voltage across it divided by the resistance (equivalently \$I=\frac{V}{R}\$).
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Basic questions about circuit diagram
I'm new to this field, and I found the below circuit online.
My intention is to use it to connect an Arduino to an 8-PIN Yaesu Rotator controller.
My questions are:
What are the parts that I've ...
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LTspice param, resistor
Is this correct answer for question given?
Parameterize one of the resistors and investigate the effect of the size of this resistor on the output voltage if the input voltage is 10V and the ...
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Characteristic of a Resistor/Diode Simple Circuit in LTSpice
Our teacher in class instructed us to experiment with a resistor/diode circuit in LTspice. The goal is to display the I-V characteristic of the resistor, as well as that of the diode, and test them ...
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LTspice temperature
Is this rightly done when doing in LTspice?
Find out the effect of temperature in the range of -20°C to +100°C on the magnitude of the value of one of the resistances if its: a) the linear coefficient ...
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LTspice- resistors, currents, ammeter
How to add ideal ammeters and with them get currents of R6 and R7?
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Have I configured the correct current supply for my TFT LCD Backlight?
I am currently working on a custom PCB which integrates a 3.5" TFT LCD. I am planning on driving the TFT backlight using a MIC4801 LED Driver and want to make sure I have configured the correct ...
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Apparently open circuit resistor with 5 bands and white final band
I'm trying to measure this resistor using an analog multimeter which has resistor parameters from X1 to X10k, but whatever parameters I set to, the needle doesn't move.
The resistor unusually has a ...
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Thermally isolated resistors
I am trying to simulate movement for a PIR sensor in a testbench. This was previously done with two incandescent lights that alternate but this method results in some false negative results.
Firstly, ...
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Connecting a multi meter across a single resistor
simulate this circuit – Schematic created using CircuitLab
When I connect a multi meter to AB it shows 5V, but isn't the resistor supposed to decrease the voltage/current? V=IR (5 = I*1000) ...
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Tolerance on a resistor when looking at a schematics
In the schematics at the end of this document, there are a bunch of resistors. The author says in a footnote:
Part Notes, All Pages:
Unless noted:
Resistors are 5%, 0.12 W, or better, for standard 5%...
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Japan's Maglev Train propulsion and guidance system
Above image is taken from Japan's Maglev Train youtube video by Lesics at here.
If the electromagnets along the two walls used for guidance of the train (So that it does not hit the walls) is made up ...
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Why does connecting a single resistor across 5V not decrease the voltage?
When I connect a multi meter across BC and AC I get the same reading, both show 5V, but isn't the resistor supposed to decrease the current/voltage?
simulate this circuit – Schematic created ...
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How to prevent a nichrome wire from melting under variable energy?
I’m experimenting with a DIY “sand battery”.
The “battery” is a pot lined inside with an insulator and filled with sand. The sand is heated by a nichrome wire placed at the bottom. The wire is ...
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Kirchhoff's Law of Voltage and Kirchhoff's Law of Current [closed]
Take a look at the circuit image below. Calculate:
The current passing through each resistor and the sources of voltage and current (magnitude and direction).
Voltage at each resistor. Label V with ...
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Looking to replace a failed resistor when the color bands have burned away
I have a TwinStar International CFI-470-10 "electric fireplace" -- a quartz heater in a faux fireplace enclosure which is lit by an incandescent bulb and a pair of colored LEDs. A while ...
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I need help identifying a component on my ps vita motherboard
I need help identifying a component on my PS Vita 2000 motherboard. It seems to be a resistor of some sort that is connected to the ID pin out for the micro USB and it is a millimeter in length.
I’m ...
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How can I design a beta modulator block
I am simulating a block beta modulator, but the problem is to switch uses in that block. What component do I have to use in place of U3? I did not find this type of any component in LTspice library ...
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I'm trying to understand this PCB. There seem to be some resistors that don't go anywhere
Do R7 and R2 connect to each other? It looks like they don't. It seems like there is even a black line separating them, but doesn't that then mean that there is no path for electricity through those ...
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Why is the green LED not lighting up?
I suppose the green and red are connected in parallel state.
Why is the green one not lighting up?
Why is it not green-1, red-0?
3. I am using a 9V battery. How are the bulbs even lighting up? ...
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Why is resistance (inversely) proportional to area instead of circumference?
TL;DR From the Veritasium-vs-ElectroBOOM debate about the 1 m / c question, it seems to me that most properties about conductors depend only on surface charges. So shouldn't quantities like resistance ...
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Resistor right at the output of op-amp
I am puzzled by the use of these resistors R227 R228 and R210 in the non-inverting amplifier circuit below:
My spice simulation does not allow me to understand the use of R227, the only thing I ...
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Can I do voltage division for parallel resistors only?
I understand that voltage division is possible for resistors that go "one after another". However, I was asked to do this for resistors that are parallel. But I could not find any info on ...
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Quick Resistance Calculation Check
In the following circuit, I have to calculate the resistance between AB :
thus \$R_{AB} = 2 + (4 || (9 + (6 || (2 + 6 || (10 + 3 || 6)))))\$.
This is the equivalent circuit that I imagined :
...
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Calculating the resistance between A and B
Im tasked to calculate the resistance between A and B, i did a first into it by transforming first upper and very lower triangle into the star transformation and adding the resistances that were in ...
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Noise floor of an unmatched resistive network thru PSD calculations
I am modeling the PSD of various loads to calculate noise floors. I have various load terminations from 25 ohms to 250 ohms.
Per Johnson-Nyquist, the noise floor on a resistor when load and source are ...
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Potentiometers for vocal mics
I want to mute the output of a wired headset mic so that when the power pack is turned on it doesn’t make a pop through the PA. I bought this little passive volume control, but with the volume fully ...
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Can a voltage divider be used to safely lower pull-up voltage?
I'm working with an LTC2950 pushbutton on/off chip that's meant to toggle the enable pins of voltage regulators based presses from a momentary pushbutton. The LTC's enable pin is open drain and is ...
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E series Components and Information
What electronic components are made using the E96 and E24 series?
I couldn't find any sources to learn about the E series. Can you please help me?
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RC + DIode Problem
Consider every component to be ideal.
V_in is a square pulse with dc level 0 and amplitude = 10 (Basically square pulse at +-5V)
Find v_out vs time (draw the waveform)
Solution : im not sure whether ...
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What role does the resistor play in this circuit?
This is a constant current discharge circuit. What role does the resistor play in this circuit?
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Spice Software Supports Parameterizing Sub Circuits?
I have Multisim and I can't figure out how to add value fields to my sub circuits or hierarchical blocks.
Let's say I'm making a sub circuit that is simply a voltage divider... so I have two resistors ...
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Designing my own scale with 0.01 gram resolution [closed]
I'm aiming to design a weighing scale with a resolution of 0.01 grams. I'm familiar with basic electronics, but I'm not sure where to start to achieve such a high resolution. Could anyone provide ...
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Multimeter range
I've been using a small multimeter meter and the problem is that anytime I want to measure amperage that exceeds 200 mA, I have to switch the red probe the 10 A port. Unfortunately, I can't get the ...
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Power dissipation of PCB trace resistor in current limiting application
How to I calculate the width of a PCB trace to survive use as a current limiting sense resistor?
I'm looking at a low-side current limiting application like that shown in the schematic. The value of <...
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Maintaining Linear Temperature / Voltage-Drop Relationship Across Thermistor While Stepping Down Input Voltage
I have a 6VDC power source that is exciting an NTC Thermistor R1 (resistance of the thermistor decreases as the temperature increases, but the relationship is not linear). There is a precision ...
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Two sets of resistors with one switch
My goal is to switch between two sets of five restistors. The goal was to use one switch to change the sets. By pushing one of the five switch the specific resistor of the set is connected between ...
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What kind of pins are used on the end of a force sensitive resistor strip? How can I fix a strip with broken pins?
I have two force sensitive resistor strips from Sparkfun where the pins have been damaged.
(One of the pins melted off when I heated it up too much with a soldering iron. The other got ripped out by ...
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Resistors value changes when measured
I've searched this forum for the past few days and I didn't find any solutions or problems similar to mine.
I'm working with a ne555 in astable mode with a configuration that, theoretically, should ...
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Getting four times the power by arranging four resistors
If I'm given four resistors of value R and power rating P (each resistor dissipates up to P), what are ways I can arrange these resistors so that my circuit has a power of 4P and resistance of R?
One ...
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RC circuit for EDM machine pulsing backwards
I am building a hackaday EDM machine project. Same as picture attached minus the 3D printer board and with a 120 V, 9 Ω setup instead.
I measured my voltages with a multimeter and across my electrodes ...
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CAN Resistor Location Help
Having discussion at work today and wondered if someone could help clear my mind.
We are creating an RS432 network to control 3 aircon units.
The network requires termination using 120 ohm resistors, ...
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How to accurately measure a variable resistor?
I need to get a measurement from a variable resistor, ranging from 10-180 Ω. Measurement shall be better than 1% over a room temperature ranging from 5 to 45°C. This variable resistor is activated by ...
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Resistor divider for power supply
I have a UM66 melody generator IC which requires a supply voltage in the range of 1.5-4.5 V according to this datasheet. I am using a 9 V battery to power the IC and as far as I have researched, ...
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Considerations for ratings when replacing a power resistor on a vintage PSU
I am replacing a component on a vintage PSU (1986). The component is an 8.2 kΩ wirewound power resistor.
The resistor might actually be newer than the board; it looks to have been installed after the ...
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Latching with MOSFET
I am struggling to have the circuit below working on LTspice. Indeed, as I understand it when the switch is pressed the LED should change it's state (turn on if off / turn off if on). The switch is ...
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Low frequency asymmetrical led blinking circuit, lacking thermal stability
I'm trying to use a NE555D to achieve a 500ms on, 1500ms off, duty cycle. The exact timing is not that important(+-20%).
But my problem is that when the temperature changes it greatly effects the ...
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How can I get the V-I characteristics of negative resistor of Chua diode
I want to simulate the Chua circuit in which a negative resistor is used. I want to simulate the V-I characteristics of Chua diode. But it does not get the same result as shown in book or papers. ...
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How to select correct resistor to protect potentiometer?
I'm planning to use potentiometer in a circuit. I know when potentiometer reaching low resistance, big current/power could burn potentiometer. How could I select correct resistor to protect my ...
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What are pull-up resistors for and how are their values calculated?
I have some questions related to pull-up resistors. Just trying to understand in depth here.
Why do we use pull-up resistors on the input pins of a microcontroller?
Can I directly connect GPIO input ...
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If I parallel a 0 Ohm wire with another 0 Ohm wire conducting current in a circuit, what would the equivalent resistance of the two 0 Ohm wires be?
And what is the current distribution of each wire?
I am wondering this question because the formula of paralleled resistance yields an undefined answer of 0/0.
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