Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [step-down]

For questions about stepping down voltages. Consider using in conjunction with related tags such as "dc-dc-converter", "buck", "transformer", "ac-dc", etc., if applicable.

For questions about stepping down voltages. Consider using in conjunction with related tags such as , , , , etc., if applicable.

280 questions
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Is it possible to step down 240 AC to 5 DC without transformer?

Microcontroller which is controlling mains voltage circuit requires 5 volts to operate. Is it realistic to use diode bridge followed by capacitor to straighten the ac wave and then use voltage divider to get 5 volts from 240 without actually burning…
flowian
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Do Step-Down Transformers Increase Total Power Consumption?

Firstly I am not at all experienced in electrical matters so forgive any wrong terminology. Here's the situation: I recently moved out of US to a country that uses 220v. We have a single phase step-down transformer that provides 120v to the entire…
mFabien
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Step-down with external mosfet - why heavy current surges?

I built this circuit, which is supposed to deliver currents up to 20 amps (when everything else works...). The purpose is (eventually) to build a constant current source (as opposed to a constant voltage source) which will be used for anodizing…
jjstcool
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Simplest way to reduce voltage from ~48v to ~36v

(I'm very much a beginner with electronics, so I apologise in advance) I’m trying to use a 48v battery on my 36v ebike controller. The controller itself can deal with the higher voltage, but it has a hardcoded limit of 44v, which it reads from a…
Tpw
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Converting 8V AC to 8V DC - bridge rectifier gets very hot while idling

I am tinkering with an Arduino and recently had to convert 8V AC to 5V DC in order to run it. The project is a custom doorbell, which gets the power from the doorbell transformer (transformer is located in the basement). The doorbell transformer is…
Maximilian Wiens
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Drop voltage a bit

I have this ATtiny13a mcu led setup that uses total of 33mA when both leds are on and it works perfectly when powered through usb output. My problem is that now I want to power it using a 6V 500mA wall adapter, so I want to drop the 6V to below 5.5V…
Kokachi
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Double Bridge-Rectifier Circuit Question

I am up to building a NE555 controlled PWM circuit that will power a 220v heater. NE555 will use a typical configuration and will drive a 20N60 Mosfet. The mosfet Vgs(th) is 10v, so NE555 needs to be powered by a 12-15v power supply. Because…
Jimmy Falcon
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Is this power supply universal input voltage?

I have this Playstation 2 power supply which was originally run at 110V input. A fellow member of this forum suggested that there might be a good chance that it could a universal input voltage and might work at 220V AC. I have taken a look at the…
Kokachi
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Cause for failure after short circuit Step-Down Converter Input

I'm currently evaluating the Semtech TS30042 step-down converter. My input voltage is 24V, output voltage is 5V. I followed datasheet recommendation in my layout in most aspects. The problem is, as soon as I short circuit the 2 clamp input ports…
bkausbk
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Best approach to step down 220VAC to 160VAC?

Hey Electrical Engineers, I'm a newbie to electrical engineering (I am a software developer by trade and am starting to work with Raspberry Pis and want to learn about basic circuit design). My first project involves converting an LED traffic light…
andrewniesen
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Buck converter - Spikes on output at switching frequency

I've been using LT1158 to make a step down switching regulator. I have an input frequency of 50kHz and this is my circuit I put 22 Ohm 50 Watt resistor on CON1 as a load. I got this output measured from CON1 its 5us/div VIN = 24V input = 3.3V 50%…
Reaper1412
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Input voltage for feedback pin on LM2596 Voltage regulator

I am using LM2596 for a dc supply where I could alter the output voltage. Datasheet here. I have setup according to page 9 "Adjustable Output Voltage Versions". Everything worked fine. The output voltage alters as I changes the value of R2…
MW_hk
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Using resistor to drop voltage in circuit with changing current

I have no problem calculating and understanding how to drop voltage using resistor for circuits with purely resistive loads - for example look at much current will an LED draw, subtract source and LED voltage and just use Ohms law to find out the…
Lukáš Řádek
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Can this Raspberry Pi UPS circuit work?

I created following UPS circuit to shutdown my Raspberry Pi 3A+ properly: I would really appreciate if somebody can review my circuit. I know it's a little bit hard to read, but I'm sorry. I'm a beginner in creating circuits. The UPS is powered by…
Manuel Neff
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Step down converter LM2596 with voltage spike on output when powering up, destroys subsequent circuits

I use this step down converter with input 30V DC and output set to exactly 5V. At the output I connected an ESP8266 (WEMOS D1 mini, has 3.3v regulator on its board) and an MP3 player module (DY-SF5W.) One thing is, I experience sparking on the…
markus germany
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