Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [passive-components]

Passive components are not capable of power gain. This could include resistors, capacitors, inductors, diodes etc.

In electrical, computer or storage systems, passive components are those that are not capable of power gain. This could include the chassis, capacitors, resistors or enclosures that do not require electrical power to operate

96 questions
176
votes
6 answers

What is the reason that the value "47" is so popular in electrical engineering?

We often see component values of 4.7K Ohm, 470uF, or 0.47uH. For example, digikey has millions of 4.7uF ceramic capacitors, and not a single 4.8uF or 4.6uF and only 1 listed for 4.5uF (specialty product). What's so special about the value 4.7 that…
MandoMando
  • 3,242
  • 3
  • 22
  • 29
64
votes
3 answers

Why are there only four passive elements?

I've read that there are four types of passive elements: resistances, capacitors, inductors and memristors. The memristor was predicted 30 years before it was produced. But why couldn't you invent other type of passive element? Is there a proof? The…
jinawee
  • 1,086
  • 9
  • 12
38
votes
8 answers

Add a passive hardware token using a 3.5mm jack

I have a box that I made for my niece, which allows her to exchange voice messages with me. It is powered by a Raspberry Pi and features two buttons, a LED, a microphone and a speaker. Now, for Christmas I want my niece to be able to exchange these…
Besi
  • 715
  • 7
  • 17
31
votes
2 answers

A PCB for a Drone

I'm making a drone, and would love if somebody can review my work on the PCB layout. Image (red is top, blue is bottom, circles indicate holes and side transfers purple is glue): What is supposed to happen: Input from the radios is PWMs 1-6, which…
user86234
27
votes
5 answers

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 into those two main categories at all? Some…
Rev
  • 10,017
  • 7
  • 40
  • 77
19
votes
2 answers

What is the dual of a diode?

A diode has an exponential I-V curve. To a first approximation, it will pass whatever amount of current is required to keep the voltage across it constant. Is there a passive component that will (approximately) drop any amount of voltage to maintain…
user253751
  • 11,998
  • 2
  • 21
  • 37
17
votes
4 answers

Ceramic (MLCC) versus Tantalum capacitors

From the perspective of an electronics designer, but also taking into account price/cost and social considerations (see Coltan mining and ethics link below), I tend to avoid Tantalum capacitors under many circumstances, while favouring Multi-Layer…
jose.angel.jimenez
  • 2,052
  • 1
  • 14
  • 23
16
votes
10 answers

Schematics for a simple radio transmitter that can be built only with passive components?

Fantasized in some of the survivalist, post-catastrophic novels, movies or docudramas is the radio built only with handcrafted or scraped components. Beyond the popular appeal of this stories, I think there is a core of truth and passive elements…
Eduard Florinescu
  • 583
  • 2
  • 13
  • 27
15
votes
8 answers

Why, in a passive circuit with a sinusoidal input, do all voltages and currents have the same sinusoidal behavior as the input?

I am familiar that in any circuit composed of linear passive elements and a sinusoidal input, all voltages and currents through and across any element will exhibit the same sinusoidal behavior and frequency as the input; that's how passive filters…
mjtsquared
  • 707
  • 5
  • 22
13
votes
3 answers

High speed passive probe - contradiction between authors or different points of view?

In a document Hiscocks et al. describes some basics of Oscilloscope probe theory. The document is very understandable and seems coherent. Notice in particular that for him, the bad guy is the parallel capacitance of the coaxial cable and of the…
MikeTeX
  • 1,834
  • 1
  • 13
  • 32
12
votes
6 answers

Other than cost, is there a reason to not use higher rated components than called for by design?

(Apologies upfront if this question seems too vague, I'm trying to formulate the problem statement as I ask this) I'm thinking about circuit assembly in a high component variability / low MOQ environment, from the standpoint of passive components.…
kolosy
  • 2,288
  • 6
  • 29
  • 51
11
votes
7 answers

Do manufacturers try make their components as close to ideal ones as possible?

I was wondering what developments are done on electrical components today. Do manufacturers try to make the electrical components they sell as close to the ideal model as possible? So for example, is the goal for their fixed resistors to behave…
blue
  • 125
  • 5
7
votes
1 answer

Issues with going to small passives

I'm going to be working on my second major design where size is the number 1 goal. What are the theoretical issues going with 0201 or less for resistors/capacitors, besides soldering difficulties?
Vanush Vee
  • 457
  • 1
  • 4
  • 9
6
votes
4 answers

Choosing SMD size for passive components

The passive components like resistors, capacitors, inductors are made up of a multitude of materials and come in a very wide range of package sizes. We could get the same value of resistor, capacitor and inductor in various sizes. I assume that…
gyuunyuu
  • 1,933
  • 7
  • 31
6
votes
5 answers

How to inverse behaviour of a switch?

I have a sustain pedal (which is just a momentary switch!) with the wrong polarity (according to the device I'm using it with) : circuit is CLOSED when pedal is pressed circuit is OPEN when pedal is released I would like the opposite. Is there an…
Basj
  • 1,856
  • 4
  • 27
  • 48
1
2 3 4 5 6 7