Questions tagged [boost]

A non-isolated DC/DC converter topology.

A boost converter is a non-isolated DC-DC converter topology used to step up voltage. It is one of the most fundamental converter topologies in existence.

The basic boost converter power train is comprised of an inductor, a diode, a switch (usually a MOSFET or transistor), and a capacitor.

From Wikipedia

The duty cycle of the switch determines the ratio of load voltage to supply voltage:

$$\frac {V_{out}}{V_{in}}\mbox=\frac{1}{1-D}$$

or

$$D=1-\frac{V_{in}}{V_{out}}$$

Wikipedia: Boost converter

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Step up 3.3V to 5V for digital I/O

I normally use an Arduino for my projects because it has 5V inputs and outputs and has 5V Vin so that makes life very easy when interfacing with 5V components. For this project I want to use a Raspberry Pi because I want to hook it up to a display.…
Huckle
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Least expensive way to boost DC voltage

What would be the least expensive way to boost a DC voltage? The aim is to convert 1.2 V/1.5 V (from an AA/AAA cell) to 3.3 V to power a small 8-bit microprocessor, like Atmel ATtiny45 or ATtiny2313, and also (if possible) 6 V to power a…
bdutta74
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Why should I worry about a motor causing my supply voltage to shoot up when the back-EMF can't exceed the supply voltage?

I have heard people say that in motor control circuits, one must take precautions to keep the motor from feeding back into the power supply, causing the supply voltage to rise, consequently breaking things. But how can this be? Unless some external…
Phil Frost
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What do the "optional" resistor and capacitor do in this circuit?

I'm designing a circuit that includes a boost converter with a few mysterious "optional" components and I'm trying to decide whether or not to include them. Does anyone know what they do? At first I thought they might be some filter but now I'm not…
Steve Marwin
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Regulated Joule Thief: why it works?

Please explain to me why this circuit can give me a regulated 5 V? I understand the Joule Thief part, but why the regulator part work? simulate this circuit – Schematic created using CircuitLab Especially, why the Zener diode D2 is crucial at…
Maxthon Chan
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Is it really possible to "boost" 6 V DC to above 50 kV? Or even 400 kV?

I am trying to create an arc generator and I have read about the marx generator but I am looking into more compact modules like the image below. All the ones I have found seem to be fake and actually supply less than 1/10th of what they are…
stenlan
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Why is my simple boost converter giving me such a high peak output voltage?

I am trying to understand switch-mode power supply fundamentals through a simulation in LTSpice. I wanted to build an excruciatingly simple boost converter circuit following a teaching model often given in textbooks, but I can't get this thing to…
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Noise problem with buck/boost switching regulator

I am designing a electrical device for a research project (I'm a PhD student, but unfortunately not EE!). More info on the device can be found at http://iridia.ulb.ac.be/supp/IridiaSupp2012-002/ The last prototype had a problem with the power…
arnuschky
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How to filter out the switching noise from a DC/DC converter

I've set up a power supply using a MAX632 DC/DC Boost converter to bring up voltage from a small 4.5V battery, then I'm using a LM2940CT-5.0 linear regulator to bring it back to 5V, which the voltage the rest of my circuit is designed for: simulate…
jmgonet
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Joule Thief - operation and the 'supercharged' version

I've made a Joule Thief, and it works fairly well, but not as well as I would like. It's powering a 3.2v LED from a 1.2v battery, but it's very dim. I'm hoping that increasing the voltage from the JT will improve it, but I'm not sure how to…
Alex Freeman
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Is it better to boost or buck?

I'm making a solder fume extractor from an old PC fan (4-pin PWM), driven by a mid-range PIC. The fan needs 12V @ max 0.28A for power and a 5V PWM @ max 5mA to control the RPM. So I'll be running the PIC at 5V and therefore I will need both 5V and…
Roger Rowland
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Routing a buck/boost DC/DC converter

I need some help with the layout of a power supply. I botched the first two iterations as I do not have the necessary experience, and I would like to avoid another costly run. For the sake of completeness, here is the previous (related)…
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Why are boost/buck converters never fully integrated/all-in-one?

Moving from small arduino applications to higher-power applications for work, I've had to switch from using simple linear regulators to switching boost/buck converters any time a different voltage to what is available is required. This has been much…
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What is making my DC/DC converter's capacitor to blow up?

I'm having some capacitors blown up and I am not sure what's the cause of this. It is definitely NOT OVERVOLTAGE and NOT in WRONG POLARIZATION. Let me introduce the scenario: I have designed a double cascaded Boost converter using this scheme: Vout…
KenshinARG
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Minimum Switching Frequencies in Boost Converters

Why are switching frequencies for boost converters above the 100kHz range? If I understand correctly, as the frequency increases from 100kHz upwards, the ripple current that is created from the inductor decreases, the current change over time…
Translucent Dragon
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