Questions tagged [components]

Components are the most basic elements in an electronic circuit. Characteristic is that they're in a single package. There are passive and active components, from as simple as a zero -ohm resistor to as complex as a multi-billion transistor IC.

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37
votes
1answer
62k views

How do I identify SMD components? (or how do I identify any component)

How do I identify the markings on an SMT component and match it up with a part number so I can be a good designer and actually look at a datasheet (and read the whole thing)? Or identify a part to ...
81
votes
4answers
50k views

What kind of components are black blobs on a PCB?

In low-cost mass-produced items I often run into black blobs of what looks like resin applied directly on top of something on the PCB. What are these things exactly? I suspect this is some kind of ...
49
votes
18answers
41k views

Which electronics components should I always have on hand?

I am thinking about ordering up some parts for every day use. I am thinking about making one big purchase so as to minimize on shipping and other charges. What are some of the components that any ...
16
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6answers
9k views

How to find Junk yards [closed]

I want to find junk yards to get components, transformers etc. When I search google, all I see is "we buy junk" How can I find where the junk is like broken microwaves, tv's etc? I live near Denver,...
43
votes
8answers
5k views

What tools, equipment, and techniques do you use to solder fine-pitch SMT parts?

Possibly many questions have been asked on soldering smd parts, but I haven't found specific answers, Like: Do you use a watchmakers lens or some other type of magnifying glass while soldering these ...
7
votes
3answers
12k views

Which SIPO chip is better, 74HC4094 or 74HC595 or something else?

I want to drive lots of LEDs in a spinning persistence-of-vision (POV) device. I need one output pin per LED, because matrix techniques don't work right in spinning POV devices. A serial-input, ...
44
votes
5answers
41k views

Triac versus Relay

What are the scenarios where Triacs can not replace a relay or vice-versa?
90
votes
29answers
86k 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 ...
53
votes
4answers
100k views

What kind of glue should I use for PCB-mounted components to avoid vibrations?

I want to protect the PCB-mounted components from vibrations. What kind of glue/substance should I use? What are the most prone to failure components due to vibrations?
35
votes
9answers
20k views

Organizing electronic parts? [closed]

I've got one of these cabinets, which I intend to use for storing electronic components: It has 24 drawers (each 175 x 69 x 37mm). Every drawer can be subdivided into up to six compartments by ...
23
votes
3answers
28k views

Standard nomenclature for component types

What prefixes should be used on reference designators for components of various types? I think we can all agree that "R##" refers to a resistor, "C##" refers to a capacitor, and "L##" refers to an ...
23
votes
5answers
179k views

Differentiation between passive and active components

While I (most of the time) know from experience what components are generally considered active or passive, I have yet to come across a satisfying definition. Why do we divide electrical components ...
15
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4answers
3k views

Why do Solid State Relays cost so much?

Solid State Relay (SSR) Crydom CN240A24: Eur 10.72 Same function with basic components Optocoupler MOC3043 (zero-crossing detect, triac out): Eur 0.726 Triac BTA06-600CWRG (snubberless): ...
7
votes
3answers
28k views

Dots in a transformer symbol

I came across this schematic: What do the dots in the transformer indicate?
3
votes
1answer
11k views

Altium: How can I edit a component from a library

I downloaded a library from the internet and I want to create a new PCB component using the ones in the downloaded library with little editing/changes (such as the footprint). Is that possible? How?
6
votes
2answers
2k views

What's a potentiometer with four terminals in this schematic?

I'm reading the datasheet for a TDA2005 IC. In it, there's a application circuit schematic with two potentiometers that have a fourth terminal in it. See below: The components I'm talking about is ...
38
votes
11answers
4k views

Is there a dual of the transformer?

Capacitors and inductors are duals of each other. A transformer is made of two inductors, and transfers power through mutual inductance, through the magnetic near-field (right?) Also, you can vary ...
37
votes
7answers
4k views

Is there any reasoning behind component names?

All the components I own have strange names, like a transistor called 2N2222 and a motor driver called L293D. When you see these kind of things writen down do you instantly know what it means or do ...
25
votes
4answers
31k views

VHDL: Component vs Entity

I am wondering what is the difference between component an entity. I would like to know in which cases is better to use components instead of entities. Thank you so much.
3
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3answers
2k views

How to choose components for a circuit

I designed a simple circuit: that I would like to put components on - the point of the circuit is to light the LED when the voltage source is above 4 volts (it won't be more than 5), so I am looking ...
7
votes
4answers
3k views

What is a general set of components for a robotics hacker?

I am playing around with a few projects and looking at a few more online. I've had to make some trips to the local electronics shop for a few basic necessities like LEDs, resistors etc. It got me ...
18
votes
3answers
43k views

How do filament LED bulbs work, looking very similar to incandescent bulbs?

Filament LED bulbs use very narrow strips containing the LED, which look similar to filaments of an old incandescent bulb: They look like a normal bulb with large "old-style" coal filaments, and are ...
11
votes
4answers
4k views

How do I identify this component? It just says 0 on it [duplicate]

Can anyone help me identify this component? It just says 0 or D on it (I think it's a zero). I tested it for conductivity with a multimeter - doesn't seem to have any (tried both polarities in case it'...
7
votes
2answers
1k views

Why are the “common” resistors and capacitors rated the way they are?

Very newbie question here...one to which I've been unable to find an answer in any of my books or online resources. Whenever I see a capacitor/resistor assortment that features the most "common" ...
8
votes
1answer
7k views

NMOS FET selection for reverse polarity protection

I am working on a reverse polarity protection circuit, similar to that in Figure 2 of SLVA139: Reverse Current/Battery Protection Circuits. Here is my circuit: My case is slightly more complex due to ...
18
votes
5answers
1k views

Is anyone producing discrete memristors?

Is anyone producing these that I as a hobbyist can play with in my circuits? If not, where can I go to find out how to make and measure the performance of one? Edit: I came upon this link featured ...
15
votes
3answers
2k views

Can you identify this component?

This may be obvious to some, but not to me. I am an IC design engineer, as such I rarely do any practical work. This morning I had to fix some electronics which were custom made by a third party for ...
13
votes
1answer
669 views

Why are the E-series numbers different from the powers of 10?

The E-series numbers are the common values used in resistors. For example, the E6 values are: 1.0 1.5 2.2 3.3 4.7 6.8 As you can see, each is about \$10^\frac16\$ apart. But I wonder why they aren'...
7
votes
2answers
2k views

What are the characteristics of a memristor?

This is an in-spirit follow-up to my earlier question. So I'm an electronics hobbyist, and I've been curious for a while about the proposed new component, the memristor. My research has turned up ...
2
votes
3answers
11k views

1N34 / 1N270 obsolete

When I search for 1N34 on Mouser I get nothing, and when I search for 1N270 diode I only find a note that it is obsolete. What is now used in place of this part? I am using Ronald Quan's book on ...
11
votes
4answers
4k views

What exactly gets “worn out” and damaged by heat?

It's quite common knowledge that heat is bad for electronics. That constantly high temperature decreases the expected lifetime of computer parts even if they are not overheating per se. If, for ...
5
votes
4answers
3k views

Which diode to use on my RC switch debounce circuit?

I am choosing parts to build an analog RC switch debounce circuit. I plan to implement the circuit described here: http://www.ganssle.com/debouncing-pt2.htm (see "An RC Debouncer"). (source: ganssle....
4
votes
5answers
2k views

Is it possible to make a complete analogy between electricity and something more graspable? (e.g. fluids)

A similar question has been asked here, but mine is more general. Here is the background: it seems to me that electricity is not so intuitive as it may sound. For example, many (unskilled, as I am) ...
3
votes
3answers
1k views

Long-lasting electronics items

I am trying to find long-lasting items -- to buy in bulk. The idea is to order them for a lifetime. What are long-lasting electronic items? Which items are good idea to stock? I have tried to get ...
1
vote
2answers
596 views

What component is a VZ reference designator for

The board I'm looking at is a modem board from a fax machine. There are 2 identical components labeled VZ1 and VZ2 on the board, both components have F175 on the face and have 2 SMC leads. One of ...
1
vote
3answers
4k views

Help for identifying pinout of unknown mp3 chip

I'm trying to use a cheap mp3 player to play song using Arduino, I couldn't find the datasheet of the main chip but I made some progress identifying some pins. ...
8
votes
4answers
18k views

How do I build a bracelet that vibrates once every n minutes? [closed]

I intend to establish a few new personal habits that eventually become second-nature to me. To assist myself, I want to wear a bracelet that vibrates every, say, 5 minutes all throughout the day as a ...
8
votes
3answers
982 views

Does the frequency of a crystal influence its height?

Here is a picture of two crystals: Does the difference of frequency explain why the 6 MHz crystal on the right has a lower profile than the 5 MHz one ?
6
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5answers
2k views

Testing points in PCB

I am designing a prototyping platform called evive. It is a learning cum prototyping platform for students and makers. Since many times we requires debugging of our circuits, so I thought to include ...
4
votes
1answer
2k views

What is this component and what is its use?

I found this in CRT TV on the CRT tube driver PCB. What are they and what is their schematic symbol?
2
votes
2answers
565 views

Can this temperature-controlled fan circuit be modified for different input voltage?

I want to know if this same circuit can be used for 220 or 230 volt input, and if there are any components that need to be modified. C3 has 600V capacity and C1 and C2 have 250 volt. Link to original ...
2
votes
2answers
420 views

Texas instruments component size

I am about to make a pcb footprint for this package: http://www.ti.com/lit/ml/mpds049b/mpds049b.pdf But I am not sure what the two numbers mean, for example at pin 5 that 0,30/0,15. Are these maximum/...
1
vote
2answers
85 views

What will happen if I use a voltmeter instead of an oscilloscope in a Chua's circuit?

Suppose I use a voltmeter instead of an oscilloscope in chua's circuit. Voltmeters only measure the average voltage over a short time period. Questions (please consider both DC and AC voltmeter, ...
-1
votes
1answer
129 views

What is the size of this microcontroller? Having trouble reading a data sheet

I am trying to find a small enough microcontroller for a project, but I am not familiar with the notation used to denote the sizes in this image: What does that mean when it says 12,20/11,80 SQ and 7,...
39
votes
9answers
8k views

How to read the text printed on top of every IC?

I find very difficult to read part numbers. I haven't figured out how which kind the ideal amount of light and inclination would help me. I also wonder why chipmakers don't paint the numbers in white ...
22
votes
8answers
10k views

How do components fail?

How do components fail? General rules with an answer per component type would be valuable. We can work as a community to build up a single question that holds valuable information about how ...
13
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5answers
6k views

Why are discrete four-terminal MOSFETs so hard to find?

I know that a MOSFET is a four-terminal device, but nearly every discrete MOSFET you can buy has its bulk/body/substrate internally connected to the source. Why is this? It makes it inconvenient to ...
10
votes
6answers
9k views

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 ...
13
votes
4answers
763 views

What is *actually* a *standard part*?

This is something that has bothered me for ages. I wasn't sure it could be made up as a question here, until Olin Lathrop suggested it to me in a comment to another thread. We all know what we are ...
11
votes
2answers
22k views

How do I choose component values when designing a Low/High pass RC filter?

Cutoff frequency of a RC filer is obtained from well known equation: $$1\over(2 pi RC)$$ This is one equation with 2 variables. for example R=100, C=10 has the same result as R=10, C=100. Based on ...