Questions tagged [resistors]

A resistor obeys Ohm's law (V=IR); the current through it is equal to the voltage across it divided by the resistance (equivalently $I=\frac{V}{R}$)

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Tolerance of voltage dividers with different values for R1 and R2

If I have two 1k resistors rated at 1% fed by a perfect 10V source then what is the otuput guaranteed to be? 5V ±1% or 5V ±2% or some other value? I can work out this case easily, assume that R1 is ...
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Zero ohm resistor tolerance?

This 0Ω resistor has a tolerance of ±1%. Well it would only be +1% at best because you can't have a negative resistance* but still 1% of zero is still zero? Shouldn't it be something like 0\\$\...
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What do the colors of resistor bodies mean?

I don't mean the colored bands, but the colors of the bodies themselves. They come in brown, blue, green, etc. Is there a standard? For instance, epanorama says: But there are two resistor body ...
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Variable resistor

I'm starting with electronics and I don't have a lot of resistors. Every new project I try to do, I have to buy new resistors, but they take a long time to arrive. What's the solution? What variable ...
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Using Pullup and Pulldown Resistors

I've been researching pullup and pulldown resistors after seeing them used in many digital circuits and while I understand what their purpose is, I haven't found any resource on how to determine the ...
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Inexpensive solid-state variable resistor

I have an analog audio project I'm playing around with designs for and it will need about 150 solid-state variable resistors. I plan to control these from a micro controller so a digitally controlled ...
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102k views

What's the best way to store and categorise resistors/capacitors/ICs/etc?

I did a big cleanup of my collection of parts today and I now have a big pile of parts on my desk (the majority of which is resistors). My previous method of finding the resistor value I wanted was to ...
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I can connect many resistor in parallel or series to get a final resistance I want in case when I have no necessary nominal out of the box. I wonder is there such trick that will allow me to easily ...
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1 vote
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Thermistors' colour coding same as the resistors'?

WARNING: 30V was a mistake -- better to keep voltage down 12V as a beginner! I tested it over a very short time. Got the things hot over a long time with much less voltage -- apparently not enough ...
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At what current and voltage do typical resistors explode?

I don't have an explosion chamber, so I cannot test critical values. If you explode resistors with too high current-voltage combination, does it damage your equipment, such as multimeter and DC-...
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Best shunt resistor for power meter application?

Looking for a shunt resistor for measuring power usage and was wondering if anyone had any experience with these. It should be capable of handling 110V/20A in-home circuit. EDIT: Energy monitors ...
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Should I default to pull-up or pull-down resistor with tact switches?

I understand the basic use of a pull-up or pull-down resistor, including the specific case of using it with a tact switch. When both are an option I was wondering whether I should favor one over the ...
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What is the purpose of a bias resistor?

Could someone explain what "bias" is. And why do some devices need an external bias resistor?
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Is there a correct resistance value for I2C pull-up resistors?

The datasheet of the 24LC256 EEPROM states that: The SDA bus requires a pull-up resistor to VCC (typical 10 kΩ for 100 kHz, 2 kΩ for 400 kHz and 1 MHz). I thought that any resistor with a kΩ value ...
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How does an LM7805 voltage regulator work?

How do most voltage regulator ICs work? Are they the same as hooking up a variable resistor and a voltmeter and turning the knob until you get the desired voltage?
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Red Green Blue LED

Do you need to use different resistors against each of the colours on an RGB LED?
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Why the resistor in this op-amp circuit?

Here's a circuit diagram for a signal response test circuit from the spec sheet for a HA-5195 op amp and looks like a non-inverting amplifier circuit with a gain of 5, plus the 200Ω resistor between ...
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