A switch-mode power supply (SMPS) switches been fully-on and fully-off states quickly to maintain voltage regulation. They offer lower power dissipation and run cooler than linear regulators that continually dissipate power through a transistor.

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power consumption ; when DC motor run on battery

I have small doubt about power selection for running motor. I have small dc motor Which rated for 12v , 3A(rated ). when motor run with load 4000N the current consumed it shows as 1.5A. So i have ...
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1answer
28 views

Understanding of UC384n

Can you explain schematic of IC UC3842/5? First of all here general schematic: What I can't understand is lower left corner and pins number 2(VFB), 1(COMP) and 3(CURRENT SENSE). What I understand ...
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3answers
40 views

The role of reference voltage in buck converters?

I asked a question here which made it quite clear that it's probably not a good start to make something that I plug directly into the mains. Instead, I've decided to build a low-voltage buck ...
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1answer
26 views

Linear and Switched-Mode Supply Common Shared

We have a mixed mode PCB system with both digital and analogue systems. Due to high speed they all share the same ground on the PCB, but use logical spatial separation to control noise. SO PCB input ...
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1answer
26 views

Auto electricity power switcher for two different power sources [on hold]

I had two different power sources at home, one is national and the other is the private from a big Generator. I want to connect these power sources so that when both power available, one of them ...
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24 views

Thickness planer electrical problem [on hold]

Good morning The On/off switch thickness planer doesn't want to retain when i switch it on, i changed the switch but it still doesn't want to retain, in the line to the motor is a anti-jamming ...
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1answer
43 views

Noise filtering on switching power regulator(LT3690)

I have limited knowledge in hardware design, where i get caught in the following noise issue. We found out that 1 of a switching regulator we used is interfering our data waveforms as below: ...
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2answers
184 views

How do residential analog and smart meters meassure power?

Im building my own digital meter in order to upload the data to a sql database, up to now i know that there are several parameters being meassured into a digital wattmeter: volts, current, apparent ...
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1answer
61 views

Switching supply burning mosfets, what is happening?

I have been working on a SEPIC converter for an electronic cigarette power supply. This application involves using two 3.7v INR batteries in parallel, rated for an appropriately high current ...
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1answer
39 views

Where i can select and buy ferrite toroid core for SMPS? [closed]

I made push-pull smps working on 50 khz. It has up to 90-120w power (input voltage 12v and output 24v). For transformer i am using two ferrite toroids on top of each other, it's a old USSR toroids ...
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1answer
54 views

MC33063 heating problem

I'm using a MC33063 to generate a -9V supply to power 7 TL084's. I'm using a 7805 regulator to power the 33063 circuit. However, the IC and the regulator heats up a lot -- I burned one IC due to that. ...
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2answers
77 views

Dual rail switching PSU critique

I am looking for feed back on the following power supply design. This power supply is intended to have 2 outputs: 24V @ 500mA and 32V @ 850mA. When the power supply is in standby, J1 pin 1 is @ 0V, ...
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1answer
29 views

Power switchers copper fill / region

When is it considered that too much is too much when it comes to copper fills on DC-DC switchers. I am currently laying out a Buck, 3 Amp max output. Every literature that I have scanned before ...
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47 views

EMI filtering at end of a long copper wire transmitting high DC power

I have a long (20 - 50 m) copper wire for supplying DC power. One one end there is a AC-DC converter supplying 600W-1000W of power at 60V output. At the other end I have a switching type (100-140 kHz) ...
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1answer
47 views

What the output isn't correct when I use a switching power supply?

I have a circuit that it is a STM32F103RET6(Reference Manual) board and one LCD. everything work very well just one thing! PWM! when I use my J-Link debugger to supply the circuit(or USB connector), ...
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1answer
72 views

Remotely control power supply with adjustable voltage

I have a power supply unit with adjustable output voltage. The output voltage is adjusted using a potentiometer. However, I need to change output voltage remotely and dynamically. What kind of ...
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1answer
55 views

How to MOSFET to drive 12v relay from microcontroller (logic high is 3.3V) using ZXMS6004FF

The above is part of my project design. 'BRAKE_CTL_3' is output pin from uController. It sends 0 or 1 to drive Q4 to turn it on or off. 'BRAKE_LSD_3' connect to one end of Relay. Other end of relay ...
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3answers
541 views

Converting cordless to corded: Pulsing issue

So I am rather new at electronics and electrical engineering. But here is what I am trying to do and what I need help with. Some years ago I had bought a cheap set of cordless power tools. Naturally ...
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4answers
163 views

Cheap switch-mode regulator “comparable” to LM317 [closed]

I've always appreciated the LM317 linear power supply regulator for being a sturdy workhorse. In particular, it's easy to build a simple regulator circuit which "just works" using an handful of ...
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2answers
33 views

SG6841 based SMPS output droops on load

I am repairing an Elo Touch monitor ET1515L which, happily, has dual mains and 12V inputs. It works when powered from 12V supply but struggles on mains. I see sets of capacitors for the PSU board ...
2
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0answers
61 views

Why do adapters fail when run on inverters? [closed]

It may be specific to my scenario, but I have brought more than a dozen adapters of varying voltages from different companies and all of them fail when powered through an inverter, after power is shut ...
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0answers
23 views

SMPS 85-265 Vac to 32 Vdc doesn't work for a long time

I'm developing a SMPS and I'm having some problems with heating. Firstly here is all information about the SMPS: Input: 85-265Vac Output: 32Vdc - 48W Flyback design IC: UC3842 Inductor size: EE28 ...
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1answer
31 views

How to properly ground chassis containing AC/DC switching power supply?

I'm planning to build a Digital Audio Converter as a hobby device and I had some questions regarding safely grounding the chassis. I want to purchase a power supply like this one: MicroMall(TM) ...
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3answers
71 views

What should the switch pin output of an SMPS look like on a scope

I'm continuing to troubleshoot a broken SMPS. At this point, I'm just trying to understand what components are broken, working under the assumption that it saw a voltage spike as a result of input ...
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1answer
39 views

Can a battery powered circuit experience input voltage overshoot on turn-on?

I'm trying to track down why my SMPS stopped working. One thing that caught my attention is this paragraph in the datasheet for the regulator: I'm using a 2700mAh 3S LiPo (rated at 35C, 70C peak) ...
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31 views

troubleshooting an SMPS

I've got an SMPS circuit that I put together around a TI TPS62125, configured to take 12V (a 3S LiPo) in, and produce ~3.3V. It worked. Everything was fine. Today, I go to turn on the system, and see ...
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15 views

Reprogrammable Remote Power Supply Raspberry Pi Monitor and Control

I currently have a reprogrammable power supply (HCS-3400) hooked up to be controlled remotely from an control/monitor app provided by the power supply company, Manson. The supply is connected via USB ...
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1answer
55 views

What type/topology of SMPS is this?

I'm researching designs for a simple bipolar output switching power supply and came across the design below in a ST datasheet for the MC34063A. However, there isn't enough information in the ...
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1answer
132 views

Resistor between Line and Neutral in SMPS

In Below SMPS Circuit ( Credit to:- NXP SMPS Design Tool ), in Red mark what is function of this resistor and why mid point of register is connected to Aux biasing of transformer. Thanks in ...
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62 views

MC34063 issue. Switches off every cycle

I am using MC34063 in step down configuration but the converter switches off every cycle. Following are the calculations and specifications: Vin - 9 to 12V Vout - 5V Imax - 0.3A Rsc - 0.36 ohms L - ...
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1answer
87 views

Why do wall plug power supplies use audible switching frequencies?

Every plug-in power supply ("wall wart") I have ever used starts off silent, but eventually starts to emit high frequency switching noise. It usually happens only when the charger is on, but not ...
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1answer
43 views

Switching and protecting batteries from external power supplies

my device can work from external power source as well as from two AA batteries, so voltage in this case is 3V, but external supply is 5v. I need to protect my circuit and power supplies in case of ...
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2answers
283 views

AC Power loss of inductor in a buck converter

I have a custom piece of equipment that gives a value for AC power loss (Pac) for an inductor plugged into an internal buck converter circuit. The custom equipment has an oscilloscope which is ...
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1answer
399 views

Will it hurt a non-powered power supply to see 12/24V on the output?

For an RC (mostly LiPo) battery charging setup I've got a 48V Meanwell AC->DC PSU supplying power to the charger. I'm considering simple ways to power the charger either by this PSU or directly by a ...
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3answers
129 views

Why does the MCP1650 datasheet give such a low value for the inductor in a boost converter?

I'm currently designing an SMPS around an MCP1650. In the datasheet (see page 4), the recommended value of inductor is 3.3uH. However, all the inductor size calculations I've come across (here and ...
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20 views

compare design discrete fet and pwm with FET integrated into PWM IC

Some new design of SMPS use the power FET integrated into PWM IC. Compared with discrete FET and PWM IC solution, what are the strong points and the weak points of the new design ? As your opinion, ...
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1answer
70 views

Why Some SMPS use Tiny Switch, Some use Top Switch and Some use Link Switch and Other use PWM IC. Please guide what is the criteria to select?

I saw many smps design , Some use Tiny Switch , Top Switch , Link Switch and other user PWM Control IC only. What is the difference and how to choose right one??
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1answer
36 views

low current buck converter

Just trying to find a suitable buck converter for my application, which is running off ~10-50V (12/24/48V battery banks) and supplying normally a very low load microcontroller (~1mA) but occasionally ...
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2answers
91 views

How to design a boost converter? And how to specify the inductor and capacitor values?

I want to design a boost converter with input of 48V and need to get to a voltage of 100V. How to select the inductor and capacitor values in it?
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43 views

Output Diode Snubber in Flyback Converter

I just completed making 48W flyback using TOP224. It is a fairly old Controller as well as its old design book. I looked at some of their modern ICs and design books and found out some significant ...
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3answers
38 views

Boost converter safety during debugging

When I was debugging my microcontroller-based boost SMPS I accidentally got 85V (instead of 15V as I intended) across the 1kΩ test load resistor. Does this spell a hazard for the one debugging the ...
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2answers
118 views

How to efficiently boost a low voltage high current input to a high voltage low current output

I have a 3.7V 6600 mAh lithium-ion battery that I'd like to use to power some small 6V motors that only require 500 mA. However, I need the battery supply to last as long as possible (which is why I'm ...
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2answers
204 views

What is dead time in DC-DC converters?

In a power management integrated circuit (PMIC) documentation I came across a programmable dead-time parameter for a DC-DC converter. What does ...
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0answers
55 views

How does temperature affect the performance of an SMPS?

I have an SMPS (laptop AC adapter) rated for 180 W that is presently operating at capacity. The output seems to be limited by internal resistance, but I can't really tell. I'm trying to get it ...
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1answer
77 views

Arduino UNO not working with L293D

I am creating a simple robot that is controlled by an Arduino UNO, and given instructions by a button matrix. One can press 4 buttons for Forward, Backward, Left and right on on the matrix array, ...
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0answers
78 views

Short circuit protection

I have built an AC/AC cuk converter for an assignment I am doing. It works as such, I provide 50V AC in and I get an adjustable voltage out from 0V to 50V AC, depending on the duty cycle of the PWM ...
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1answer
58 views

Switching between different batteries!

I Have got a project wherein I have to achieve this! Please neglect the charger set up for my block diagram. Since I am a newbie to electronics, I am unable to get any idea how I would switch ...
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1answer
37 views

isolated voltage

I am looking to add an isolated 10-12V supply capable of producing ~200mA to an existing circuit which has 5V and 12V rails available on the board. I would prefer to use the latter (12V) as it can ...
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60 views

Can a joule thief circuit be made to both boost or buck an input voltage?

In the normal run of things I would use a 555 or something similar to generate a PWM signal as the base for my power supply. The caveat is that for my application I need continuous operation from an ...
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108 views

Can I use a TVS diode to remove spikes in SMPS?

I have an almost working Half-Bridge SMPS that has some ringing in the output like this (not the real output, just and image I found): I have eliminated almost all the oscillation using a snubber ...