# Questions tagged [inductor]

An inductor is a 2 terminal passive device that stores energy in a magnetic field.

1,749 questions
Filter by
Sorted by
Tagged with
24k views

### What might be the cause of high pitch sound coming from a switching regulator circuit?

We designed a switching regulator circuit using a 1.5MHz, internal-switch, switching regulator (semtech.com/images/datasheet/sc185.pdf). Vin is 5V, Vout is 3V3. We have an input capacitor (47uf), an ...
• 2,240
12k views

### How do I use a transformer as an inductor?

Lp: Self inductance of the primary winding. Ls: Self inductance of the secondary winding. Lm: Mutual inductance between the primary and secondary windings. Assume that I need an iron core inductor ...
• 13.5k
2k views

So I'm still new to electronics, and I've been taking a look at Boost Converters and such (just learning power supplies and the different types)...which got into explaining inductors. Needless to say ...
560 views

### Inductor for guitar strings

I was wondering if anyone can help me with choosing a right inductor. My aim is to create circuit, which would start oscillation of a steel-core string. This would be achieved by oscillator (tuned to ...
• 435
116 views

### Stymied in search for an electronic lock [closed]

I'm looking for an electronic lock to secure a small, wooden box (breadbox-sized). The box is ordinary: one side of the lid is hinged against one side of the box. When I look for 'electronic locks' ...
• 649
1 vote
11k views

### what is the magnitude of total voltage in the below circuit?

I was working on some RLC circuits and I found a question something like this. In series RL circuit, $V_R$ = 4V and $V_L$ = 3V. what is the magnitude of total voltage ? I just thought $V_T$ = ...
• 533
20k views

### Why do smaller loads require larger inductors in buck regulators?

The MC34063 Application Note lists the equation for calculating minimum inductor size as follows: $$L_{min} = \frac{V_{in} - V_{sat} - V_{out}}{I_{pk}(switch)} t_{on}$$ But this implies that as Ipk(...
• 7,639
3k views

### Is there a something else I could use in this circuit instead of inductor?

I'm making the analog interface for MCP3909 chip , I'm having a problem in finding any inductor where I live .. I've two question :- Is there a substitute of this inductors ? What's the reason ...
• 1,578
13k views

### Why do buck (step-down) switching regulators require an inductor and diode?

So, I understand, at least at a basic level, the method of operation of switching converters, both buck and boost. What puzzles me, though, is why buck converters in particular aren't simpler. Why ...
• 7,639
280 views

### Why are these switches connected to ground?

Sorry for the vague title. This is a schematic of a Nerf Rayven foam dart gun: Why did they make the connections that I circled in red? I'm guessing it has something to do with the inductors on the ...
28k views

### What does the "L" in inductance stand for?

"R" is resistor/resistance, and "C" is capacitor/capacitance, that makes sense. But where comes the "L" for inductor/inductance come from? edit: Wikipedia says it's possibly in honor of Heinrich Lenz,...
• 9,518
45k views

### Why does an inductor behave as a capacitor at high frequencies?

In truth, I've only been told this anecdotally by an instructor, but can someone explain the physics at play? I have been told that if an inductor is driven at a high enough frequency, it will begin ...
• 928
186 views

### Norator in series with inductor/capacitor [closed]

I know that if I have a norator in series with a resistor, I can replace the resistor with a short circuit. My question is, if I can do the same with a linear inductor/capacitor?
• 119
9k views

### LM2596 Voltage Regulation Problem

I am trying to implement a switching voltage regulator from 7.2V to 5V with LM2596 by HTC Korea. Since I don't need an adjustable regulation, I chose typical application circuit from the datasheet ...
• 224
11k views

### Calculate the value of an inductor using an RL or LC circuit

Given an inductor of an unknown (though magnitude-estimatable) value, and a resistor of precisely known resistance, how can one calculate the inductance of the inductor? Tools I have at my disposal: ...
• 55.5k
7k views

### Values of inductance - what is the "base" value?

I have a selection of salvaged inductors, and I don't (yet) have an inductance meter. I would like to know what the inductances are, but I have a problem. They are numbered with 3 digit numbers - I ...
• 55.5k
3k views

### How do I make a real-world verison of this LC circuit?

I'm trying to build the LC oscillator show on the bottom of this page for some school project and I'm having a bit of problems translating the theoretical circuit into a real-world one. Here's the ...
• 22.7k
7k views

### What is this component (labelled L1)?

What is this component? It looks a bit like a capacitor, but not exactly, and it is labelled L1 on a small circuit board where there are capacitors labelled C2 and C3…
• 2,619
811 views

### Oops: shielded inductor very close to a crystal. Problem?

I've got a design that worked great on the two boards I hand assembled, but more than half of the boards from the local assembly shop are bad. I've traced the most common failure mode to an unstable ...
• 3,451
261 views

### Recommendations for essential measurement/bench tools for HV experimentation

I'm making plasma sculptures, and am also really interested in making big arcs and tesla coils. I started with some newer TV flybacks and the 2N3055 single-transistor flyback driver, and am moving on ...
• 101
13k views

### Inductance and "kick back" voltages

I'm trying really hard to understand inductors and their related kick back voltage when the current is suddenly interrupted. Example ascii art: 1 2 | | + ----- ~~~ --_-- - Where ...
• 3,296
1 vote
2k views

### Can the coil in a magnetic field be replaced by a copper mesh?

From theory, I remember that EMF induced is a function of the rate of change of magnetic flux. A generator is typically a changing magnetic field applied to a bunch of diamagnetic wires wound closely ...
• 2,911
1k views

### Data sheet inductance (R/A ?)

I have to implement a LC filter for a FT232H and its datas sheet (here) gives an example circuit (Fig. 6.1 VPLL- & VPHY-circuit). Strangely though a core-inductor is stated to be a 600R/0.5A.! I ...
• 239
1k views

### Which side of a PWM MOSFET should an inductor go on?

I have a power supply circuit that needs to supply bursts of power at 5A, 8V but only 1/4-1/8 of the time (using PWM). I wanted to smooth the current draw out on the actual source of the power, a ...
108 views

### What is the most available high-temp superconductor for samples and study?

I could only find one named Amperium on the web, but not on the eBay or any little shops. It is very interesting material with conductivity 40 times better than copper. Is it possible to buy anywhere ...
5k views

### Switching regulator: How to determine maximum inductor current?

I am trying to design a buck/boost converter with the LTC3780 chip from Linear. My specifications are: Vin = 6 to 32V Vout = 24V at 100mV ripple Ioutmax = 2A Frequency = 300kHz The datasheet uses ...
• 5,800
954 views

Are inductors usually hand-wound or bought pre-wound? For the former, how is the inductance measured? Is there some test instrument that can be used or is it done by measuring the length and radius (...
• 297
5k views

### Inductor and capacitor for GPS antenna

I'm working with the Venus 634FLPx GPS chip. The reference schematic in the datasheetincludes an inductor L1 marked "optional biasing for active antenna": What ...
• 493
1k views

### What do you call it when you add energy to an inductor?

When you add energy to a capacitor, you say that you are "charging it". (This is kind of a misnomer, since the total amount of charge in the capacitor is the same, but whatever.) But what do you ...
• 27.9k
655 views

### Should I avoid placing a SMPS inductor close to a magnetometer?

I am designing a board, which has a high current (~2A) buck-topology switch mode power supply on it, which uses an unshielded SDR0805 inductor. About 4cm from it, there is a magnetometer (combined mag/...
• 31.1k
1k views

### Building SMPS using L4960: How does the choice of inductor affect circuit operation?

I've decided to conquer my fear of switched-mode power supplies and build one. Right now, I have a L4960 regulator. Its datasheet recommends use of a 150 μH inductor rated at 5 A. My problem is that ...
• 22.7k
10k views

### Capacitors or Inductors?

So I know what they both do. Yet I don't know when you'd choose to use one over the other. There was a similar question on here, but the answer didn't really make sense to me, an electronics newb. I ...
746 views

### Peaking Inductance

Could anyone please explain the working of so called 'peaking inductors'? I know they are used to enhance the bandwidth but how do they do this?
• 31
3k views

### Measuring ferrite core parameters

I have large amounts of inductors and transformers from power supplies or other undocumented sources. They are of course completely unmarked and I have no idea what kind of ferrite material they are ...
• 5,232
2k views

### Is parallelling inductors a viable solution?

I am doing a space constrained board layout, in terms of surface area. So I found an inductor which is $15\mbox{ }\mu H$, $2.3\mbox{ }A_{RMS}$. I need about $3.5\mbox{ }A_{RMS}$, so I was ...
• 31.1k
9k views

### Is my inductor really 22µH?

I have a package of 10 inductors, all of which are supposed to be 22µH, but they all have "220" printed on the case. It does not seem right when I compare to an otherwise identical (same type) ...
• 31.1k
849 views

### Understanding when to use basic Components

So I understand AVR assembly for the most part, and generally understand the overview of microcontrollers. but when it comes to specific components (besides the obvious stuff like resistors/batterys) ...
77k views

### Inductor vs a capacitor

I'm a Trainee electrician and pc hardware enthusiast. I was just wondering why a mixture of inductors and capacitors are used on motherboards? Why not just use capacitor? I thought the inductor stores ...
• 3,219
3k views

### Shall I use a choke or a bead to filter analog power supply?

Often I have a 3.3V or 5V mixed-signal circuit with a microcontroller running in the 10 MHz range and some analog circuitry, e.g. audio or analog sensor signals, powered from a wall-wart style supply ...
• 2,890
3k views

### Plans / tutorial for sound effect generator using only analog components?

I've been wanting to make a laser gun sound effect attachment for my son's bike. Currently, I'm using the electronics salvaged from his old laser gun toys. All of them seem to use electronics hidden ...
• 3,780
1k views

### Choosing output filter inductors for switching power amplifiers

Class D PWM switching power amplifiers use an LC filter at the output to filter out the switching harmonics: Other than the inductance value, what properties are important for this inductor? What ...
• 27.9k
16k views

### What do phase dots on an inductor mean?

I have a SEPIC supply with coupled inductors. The inductors have phase dots. What do these "phase dots" mean? Is it important to have the phase dot in the same place?
• 31.1k
2k views

### Creating a coupled inductor with two discrete inductors

Is it possible to create a coupled inductor (with high coupling coefficient) by just placing two inductors very close to each other on the PCB? (Even as far as placing them on top of each other.)
• 31.1k
6k views

### Coupled inductor vs an actual transformer?

What is the difference between a coupled inductor and an actual transformer? The LT3757 datasheet mentions that I need a coupled inductor for the SEPIC to work
• 31.1k
2k views

### LC circuit: can it act as an "AC battery"?

I am curious about a resonant LC circuit. Assuming a perfect inductor and capacitor, would it be possible to tap off the energy in the oscillations to use it as a battery? Literally, it would be an AC ...
• 31.1k
10k views

### How important is saturation current for an inductor?

I have a 15µH 1.6A inductor, this one. The operating current is 1.3A, but the saturation current is 1.6A. What is the difference between these? Will the inductor work properly at less than 1.3A or ...
• 31.1k
15k views

### How important is self-resonant frequency for an inductor when used in a fast (~3MHz) buck SMPS?

I'm using the LM2734Z, a 3 MHz buck regulator. It's really fast which means it has a small inductor. One of the things I'm wondering is how important is the self-resonant frequency of the inductor? I'...
• 31.1k