Skip to main content

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.

Filter by
Sorted by
Tagged with
0 votes
0 answers
39 views

Uninterruptible power supply for wireless equipment using cheap modules and cheap batteries

I've built an uninterruptible power supply (UPS) to use in my house during power outages that last for 16-18 hours per day. The idea was to use previously bought cheap modules from Aliexpress and old ...
Zero Cool's user avatar
2 votes
2 answers
164 views

Output of a stand-alone full wave rectifier is different from the one in the circuit in which it is implemented

I'm trying to simulate an evening lamp using a NE555 timer and a relay. To do so, I'm stepping down the 230V AC household voltage to 16V by an RC circuit as shown. Now, when I take a stand-alone ...
rire's user avatar
  • 23
0 votes
1 answer
100 views

DC Voltage Step-down at High Current

I have a petrol mower with an electric-start engine. The electric start is powered by a small battery of similar size and design as you might find on an electric drill or other power tool, charged by ...
Lefty's user avatar
  • 311
0 votes
0 answers
21 views

Power distribution PCB and Li-po batteries

I am hoping to work on a project over the summer and it requires a decent bit of current. I ended up going with two 7.4 V, 5400 mAh batteries and I was planning on running them in parallel. With this ...
msalaz03's user avatar
2 votes
1 answer
56 views

Step-down, ultra-low current kVDC and boosting current [closed]

I have a constant current source that can only give a maximum of 1 μA DC but can maintain this current level from less than 1 V to a few thousand volts, depending on the resistive load. I calculated ...
nothingreh's user avatar
1 vote
1 answer
180 views

Noise during RS-485 operation

I have a switching step-down power supply SCM1301A, from which the entire circuit is powered, namely the microcontroller, op-amp, RS-485. I digitize the signal coming from the microwave module, having ...
red15530's user avatar
0 votes
1 answer
93 views

What is the "best" way to make a diy 7v rechargeable battery?

I have a device (the wii "sensor" bar, basically an IR LED array) that the literature says takes 7v. I can't find any battery offerings that come in 7v, but many that are 3.7v, so I am stuck ...
insaner's user avatar
  • 141
0 votes
1 answer
93 views

Stepping down a toroidal transformer from 35v AC dual to 24v AC single power supply

I want to use a toroidal transformer dual 35.5v AC currently inside an old power amp as an external power supply 24v AC single. There are no details on the trans but I include a pic and the voltage ...
Newager's user avatar
0 votes
1 answer
72 views

Powering a tablet from 5V, how to regulate current draw?

I'm making a circuit that controls a 24V led strip, but it has some extra peripherals too, mainly some buttons to interface with. However, I also want to attach a micro usb cable, so it will be able ...
Slalamander's user avatar
0 votes
0 answers
22 views

Combining a MP2307 (12 V to 5 V) & AMS1117-3.3 (5 V to 3.3 V)

Powersource is from a motorcycle battery (12 V) for powering my device (a ESP32 MCU) and I thought combining a MP2307 (12 V to 5 V) & AMS1117-3.3 (5 V to 3.3 V) would make my device last longer. ...
Dsydd's user avatar
  • 1
0 votes
1 answer
89 views

Circuit analysis to understand how this circuit works - PNP

I am trying to understand how to get values at midpoint_diode and also at OUT. I understand this circuit is to step-down the voltage from Vin to something that is lower and also it used to have a ...
mdabdillah's user avatar
4 votes
2 answers
255 views

TL494 step-down converter unable to run LTSpice

In previous question TL494 step-down converter high voltage LTSpice I have established that hacking around LTspice isn't going to work since in the end, schematic must be proper. However I was never ...
Kaminari's user avatar
  • 145
0 votes
1 answer
572 views

TL494 step-down converter high voltage LTSpice

I have tried to make LTSpice of step down DC-DC converter, however I cannot get it to work. I suspect the schematic is good however either LTSpice model is not correct or I made some critical mistake. ...
Kaminari's user avatar
  • 145
0 votes
0 answers
79 views

Stepping down 400v to 50v in DC

I have a 400V supply and I need to step it down to 50V, does anyone know a good way to do this? I need a solution that can work quickly (for the circuit) and doesn't catch anything on fire
jackk's user avatar
  • 1
1 vote
1 answer
125 views

Burning sound from the PSU

I am trying to make a bench power supply from an old 350W PC PSU that provides 4 lines 3.3V 8A 5V 9A 12V 11A -12V 1.5A Here is the connections diagram: I used this step down module to be able the ...
Mohamed Essam's user avatar
0 votes
1 answer
44 views

Combination of step up and step down feasible?

I have a model aircraft on which I am installing a LED kit of the same manufacturer. The EDF jet is powered by a 6s Lipo (22.2V nominal). The LED kit connects to the balancer plug of the battery and ...
dmy's user avatar
  • 1
0 votes
0 answers
130 views

Add PWM control to XL4015

I am using a circuit based on XL4015 to drive a series of high power leds. After that circuit I have a mosfet to dimmer the led. With this configuration everything woks fine. Now I want to unify both ...
Oscar Fernandez's user avatar
2 votes
2 answers
206 views

Could a device connected to one MCB/phase affect a device on another MCB/phase?

I have a 3-phase 230V residential supply. It's divided among 3 groups of MCBs all powering single phase devices. The problem I'm having is that whenever the air conditioning (single phase) turns on ...
Pavin Joseph's user avatar
1 vote
0 answers
129 views

Constant current LED driver temperature issue

I am using a DC-DC step-down constant current LED driver to power up four high power LEDs in a series connection. The LEDs are drawing a 2 A current at 100% power and they have forward voltage about ...
Lime7's user avatar
  • 33
1 vote
1 answer
233 views

What are the consequences of small bootstrap resistor (in DC-DC buck/step down specifically)?

If I understand it correctly, a bootstrap capacitor (CB) is used to store energy to turn on the high-side MOSFET (P-channel MOSFET). In DC-DC buck converters (which I use now) this happens several ...
Christianidis Vasilis's user avatar
0 votes
0 answers
33 views

Check of PDN for RF Amplifier - Revised

This is an update to my previous post. I was recommended to post it again. For optimal working conditions, HMC863ALC4TR needs Vdd = 5.5 V and Vgg = -0.75 V. I have tried to design such a network to ...
Humphrey Appleby's user avatar
1 vote
0 answers
105 views

The best way to step down 12V to 5V with at least 10A current from a PS3 power supply for a WS2812B LED strip

I am new to electronics. I had a PS3 Super Slim power supply lying around, which outputs 12V up to 13 amps. Recently, I bought a 5-meter strip of WS2812B LED strip, which needs 5V, and the recommended ...
Fahis thayyil's user avatar
0 votes
0 answers
36 views

Calculation of Power Transformers

I'm calculating transformers very roughly, with some approximate equations that I found on the internet, they are working perfectly but I'm supposing that they are oversized... They are power ...
samuel mattio's user avatar
1 vote
3 answers
112 views

Unable to start and run 12 V DC pump, only jolts

I have a 12V 19 watt DC water pump (800LPH), A 12 V DC step down converter, and two Dewalt batteries. One at 18 V 5 Ah, other 18-54 V 9 Ah. I've connected pump to step down to battery correctly, but ...
David jones's user avatar
2 votes
2 answers
73 views

How does a starter transformer work?

I am searching about chargers that are specifically for starting forklifts and other things that require, say, 12V-24V and 20A-80A. They have lead-acid batteries. These starters have a switch for 12V ...
samuel mattio's user avatar
0 votes
1 answer
33 views

5 V behaviour of Mikroe Feather click shield when powered from Feather only

The Mikroe Feather click shield supports a mode where the power comes from the Feather: In this mode the Feather board will provide 5 V and 3.3 V labeled as P5V ...
Francois's user avatar
  • 577
0 votes
1 answer
63 views

Are heating elements multi voltage? [closed]

I have a 110 volt crock pot but I live in a 220 volt country. It says it uses 270 watts. Can I just use it anyways without modification or should I try to find the interal wiring and make the heating ...
David Hofmann's user avatar
0 votes
1 answer
110 views

What is the range of the most powerful step down DC/DC converters nowadays?

The team in my lab's company, we want to start using high voltage DC to perform some tests. The electric company can supply us a line of 25kV DC but in reality we would need to chop it to get voltages ...
Santi Ospina's user avatar
1 vote
2 answers
203 views

How to calculate bootstrap Resistor in MC34163 Buck configuration

I am designing a DC-DC buck converter with MC34163DWG. I try to understand what value of resistor RB must I use at the buck/step down configuration and I also have questions about the CB capacitor. ...
Christianidis Vasilis's user avatar
0 votes
5 answers
397 views

Shielding Buck Converter

I have a simple question, and I want to ensure that nothing unexpected happens. I'm currently working on a Raspberry Pi-based robot project with a Pi camera, and I plan to power it with a battery, ...
M-125's user avatar
  • 53
0 votes
2 answers
263 views

How to decrease DC Voltage and Increase Current [closed]

I am using a buck converter to reduce source DC 12 V 1 A to 5 V. It does reduces the voltage but the problem is that it also reduces current i.e; less than 1 A. I want to keep the POWER same at all ...
Gold Fish's user avatar
0 votes
1 answer
50 views

Variable Vout of Buck Converter [duplicate]

I have been trying to understand the working of buck converter (without the use of a dedicated IC). So, I used LTspice to test a circuit on the parameters: Vin: 100 V Vout: 50 V Freq.: 10 kHz I: 5 A ...
Momobear's user avatar
  • 117
0 votes
1 answer
115 views

Check of PDN for RF Amplifier

I would like to ask you for help with the power delivery network (PDN) design. For optimal working conditions, HMC863ALC4TR needs Vdd = 5.5 V and Vgg = -0.75 V. I have tried to design such a network ...
Humphrey Appleby's user avatar
2 votes
2 answers
318 views

How can I replace a potentiometer with a fixed resistor on a buck converter?

I want to use a buck converter which steps down 12 V DC to 5 V constant DV output to power my custom PCB. I came across a buck converter in market which can do it but there is potentiometer on it ...
Ashish1313's user avatar
0 votes
0 answers
59 views

Reduce voltage ripple in wall power supply and buck converters

For my project I choose a wall AC/DC power supply (AEJ160PS12) with output voltage at 12V and intend to use some buck converters to step down from 12V to 6V and 3.3V. The chosed buck converters is ...
stefyanna's user avatar
0 votes
1 answer
97 views

Calculation of step-up / step-down output voltage

I am trying to build a step-up and step-down circuit from a DC-DC converter IC. This is from the datasheet: I have two questions in relation to this: The value of the resistor in the red box. It ...
user1584421's user avatar
  • 1,369
0 votes
1 answer
215 views

Separating 5v and 12v circuits using diodes, converters, and switches

I have drawn out a project with multiple power options. I am wondering if any of these reverse current protection diodes can be left out. If the double pole double throw switch can be replaced by a ...
Audo Voice's user avatar
1 vote
1 answer
429 views

High to Low logic level converter with MOSFET

I'm designing a sniffer circuit to tap input signals from various machines. The type of signal varies from input pulses and UART communication, the voltage varies from 5V to 12V. These are the ...
Max's user avatar
  • 557
1 vote
2 answers
513 views

Reducing a constant voltage source from 24 V to 12 V [closed]

I currently have a constant voltage source powering a PLC which outputs 24 V DC. I need to drop the voltage from 24 V to 12 V. Is there a way to do this without buying a $100+ DC-DC converter? The ...
Michael Chaput's user avatar
1 vote
0 answers
72 views

Desigining a 3S battery charger step-down buck converter

I'm a hobbyist, so my electrical engineering skills are not top notch. I'm service tech and I'm working on modifying portable coolers (thermoelectric and compressor based) where we add batteries to ...
Oxmaster's user avatar
  • 157
1 vote
1 answer
168 views

AP64501 problem

I have a big problem with the AP64501. I used the reference layout from the datasheet for my own PCB (5V output (without C4 and C6)). As soon as I put 24V on the input, the AP64501 burns out ...
nordsektor's user avatar
4 votes
3 answers
2k views

Using resistor to drop voltage in circuit with changing current [duplicate]

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 ...
Lukáš Řádek's user avatar
0 votes
2 answers
556 views

Can I use a buck converter and a 12 V adaptor to create a 5 V and a 12 V circuit?

I have a microcontroller that is powered by 5 V and some solenoids that need 12 V. At the moment I power the solenoids using a 12 V adapter and switch them on and off through MOSFETs which are in turn ...
Luuk256's user avatar
  • 35
1 vote
3 answers
148 views

How is this stepping down 12 V? [closed]

I'm positive that the microcontroller (U3) in the picture can only receive a 5 V input. I just want to know how those components (the two resistors and the capacitor by In1) are stepping down the 12 V ...
ErFiodena's user avatar
0 votes
2 answers
121 views

Are there any step-down regulators without capacitors for a vacuum environment?

I'm trying to find step-down DC-DC regulators that would take input voltages of ~30V and convert it to 5V and ~24V. I was originally looking at linear regulators such as the 7805T, but the specific ...
Runsva's user avatar
  • 177
0 votes
1 answer
95 views

MOSFET + voltage regulator usage, pull downs, common ground, schematics

As a continuation of my previous question about what type of part I'd need to control a circuit with a higher voltage, I put together schematics for what I hope would achieve what I am looking for ...
klaasbob's user avatar
1 vote
2 answers
217 views

Step-down chopper with RL load

I am studying a step-down chopper with RL load. I see that the output current waveform starts at a non-zero value (say Imin). Shouldn't it start from zero? When the switch is closed, how does the ...
Rajesh Raskoti's user avatar
3 votes
3 answers
306 views

Why is my circuit powered by a 24 VAC -> 5 VDC stepdown module releasing the magic smoke?

I have a Carrier HVAC system in which device controls are all powered by a 24 VAC pair and communicate via an RS485 differential pair. In the past I've communicated with the bus by using USB to RS485 ...
nebulous's user avatar
  • 133
2 votes
2 answers
209 views

Calculating of the maximum output current of a 12 V to 3.3 V step-down converter

I am planning to use the AP3211 step-down converter to go from 12 V to 3.3 V. The maximum current at 12 V that I can supply to the input of the step-down converter is 0.3 A. Assuming the efficiency of ...
user14665305's user avatar
0 votes
0 answers
26 views

Disabling Two Step-Down Converters Together

I have a circuit using two step-down converters (RT8299) which take in 24V and output 12V to power a 12V, up to 6A resistive load. Each converter is rated for 3A, testing has shown the current circuit ...
InBedded16's user avatar

1
2 3 4 5
7