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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What is the difference between Switching Mode Supply and Switching Regulator?

If they are not the same thing which is used where and when?
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53 views

Trying to determine if transformer is safe

I am building a switching power supply with an isolating step-down transformer. Part numbers: Controller: LT3798 (http://cds.linear.com/docs/en/datasheet/3798fa.pdf) Transformer: 750312872 ...
9
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2answers
1k views

Are typical computer power supply units leading or lagging power?

Computer power supplies often have "power factor correction" features which raise the power factor in use to levels close to resistive loads (1). I'm curious what, in the absence of power factor ...
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0answers
34 views

Why is harder to get power in the 12v rail in a smps? [closed]

A cheap power supply has the major part of his current in the 5V rail, while a certificate one has the power in the 12V rail, I get that in the 12V rail the same current will be a bigger amount of ...
0
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2answers
128 views

Noise resistant microcontroller used in high power inverters for PWM generating [closed]

In order to generate PWM pulses for driving switches of a high power(80 kW) three-phase inverter,which microcontroller family(and which member) is suitable? ,taking into account the noise effects on ...
3
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34 views

Increasing 12V Rail current on power supply for mobile computing

I am building a miro-itx slimline pc for my mobile home that is powered by solar. I have selected a GPU with a rated TDP of 120 Watts and a CPU with a TDP of 53 Watts.I purchased a DC-DC buck ...
0
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0answers
40 views

Can I use a 100-240V AC 5A Time Delay Relay to spread out startup of drives?

My storage enclosure has dual power supplies for failover. Specs for each PSU:100-240VAC 5AMax continuous output power: 250WTotal power on +3.4V & 5.V is 128W mx I need to delay initialization on ...
0
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0answers
39 views

Switching regulator discontinuous mode

I designed a step down converter for my circuit using the following converter: http://www.ti.com/lit/ds/symlink/lm1575.pdf It converts 16V to 3.3V. As I summed up the current consumption of my ...
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28 views

Computer power supply fault [migrated]

This is my first post to the site; it's been a great resource to me in both my professional and personal lives. It's about time I registered! So I went to boot up my desktop this morning and nothing ...
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1answer
44 views

What is the circuit for the PMOS driver found in synchronous buck regulator ICs?

Some synchronous buck regulator ICs sport a NMOS lowside switch and a PMOS high side switch. I understand why these use a PMOS/NMOS pair instead of a NMOS/NMOS pair, but I can't seem to make sense of ...
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1answer
52 views

Power inductor maximum DC current rating

I am selecting a power inductor for my power supply. The only significant source of current draw is a servo motor that draws about 200mA - 1A for 500 ms for less than 10 times a day. Consider the ...
0
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2answers
65 views

Switching regulator (TI LM2678) not working on load > 100mA

I am a (joung) programmeer and I recently began studying some electronics&AVR programming. I am trying to use a step down voltage regulator (LM2678-5.0) to transform battery voltage (9/12V) into ...
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1answer
39 views

switch mode power supply frequency change

I am relatively new in the field of Switch Mode Power Supplies but I was looking at the Flyback converter with an input voltage of between 30V to 88V DC and an output that would charge a 24V lead acid ...
3
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1answer
52 views

Switching Supply Noise Filter for Audio Circuit

I want to make an external power supply for various pieces of "vintage" audio gear that run on +-18V, +48V, -9V and so on. So the plan is to put several off-the-shelf AC/DC switchers (like Meanwell ...
0
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0answers
34 views

AVR decoupling capacitors in 64kHz switching power supply

I am working on a compact variable switching power supply (sepic topology) that is controlled by an Atmega328p microcontroller. The unit is powered by li batteries at 3.7 volts. Everything works ...
2
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0answers
26 views

Continuous gate drive for high side mosfet using ir2110

I plan to provide continuous gate drive for high side mosfet using ir2110. According to ir2110 application note, a 555 timer is used as charge pump for continuous gate drive but the schematic is hard ...
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1answer
20 views

Using a SMPS converter IC as a controller

I'm building an LED driver using the LM3410. The internal switch supports a current of about 2A which should be adequate for my needs, but if I need more, can I use an external MOSFET to act as a ...
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2answers
77 views

5V 5A rail controlled by 3.3v microcontroller - dual switching or power mosfet?

I think this is a common situation so hopefully an answer helps more than just me. I have a 3.3v low power MCU which will be controlling a 5v 5A run of LEDs. When the LEDs are off the system will go ...
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1answer
57 views

are sensing power supplies and switching power supplies the same thing? [closed]

What is the difference between sensing power supplies and switching power supplies? Are they the same thing?
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2answers
54 views

Current sense in SMPS, how does it work

I've read a couple of application notes where it is stated that measuring current to use that value in the feedback loop helps stability because sensing before the RC net takes a pole away (see ...
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2answers
101 views

does half bridges ICs exit?

i can't find any half bridge ic (with integrated fets) for low power (2w around 12V), all i find is full bridges for the same power magnitude. and i don't even find them under the name of full bridges ...
2
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1answer
96 views

Discrete LED Driver Topology

I have drawn the above schematic by reverse engineering a locally available LED Bulb. I was expecting to find an IC in the driver board but instead found this discrete circuit. Googling "Discrete ...
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1answer
63 views

Boost converter with 2A load

I'm trying to put together a boost converter to take a 11-14.4v input and boost it to ~17v with a max current of 2A. Most of my designs (made either by calculations done by me or a calculator tool ...
0
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0answers
37 views

Buck Converter power supply based on astable oscillator and zener diode feedback?

simulate this circuit – Schematic created using CircuitLab I've asked several theoretical questions about this before, but I've assigned values and changed my circuit quite a bit. The ...
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1answer
63 views

Step-down converter and ceramic minimum ESR capacitor

I'm building a step-down converter, based on the TI TPS5450, which provides a reference design and various considerations on the capacitor. Even on the minimum ESR required. But when states "The ...
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1answer
58 views

SMPS control components and technologies

Preface: the switch-mode power supply is a flyback power-factor corrected AC-DC converter. I'm currently using a combination of AVR microcontroller (ATmega64A) with some analog (such as DACs) and ...
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1answer
33 views

Do I need to place any additional component(s) getween isolated grounds?

Initially I bothered with this question regarding isolated flyback switch mode power supplies. However I'd be happy to investigate this question dipper. So as the output of the power supply is ...
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2answers
96 views

TPS61240 Boost converter IC is not working at all?

I am currently using TPS61240 as a boost converter for my project. As i did not have any sample previously so there was no way I could test it. I ordered the IC and placed it on my final PCB directly. ...
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1answer
55 views

What for is L1 coil?

I can't understand why L1 has four windings? And how we get -12 V if there are two diodes connected towards each other. How will current of -12 V flow? And do thos fours windings work as ...
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3answers
86 views

Feasibility of very high temperature ac-dc switching power supply

I'm involved in a product design (on the mechanical side, to be clear that I'm not an EE) where we need a very compact ac-dc switching power supply that will take 90-300vac, 50-60hz and output 5 watts ...
0
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3answers
119 views

Converting 12-220V to 12V?

Are there any Analog/Maxim (I couldn't find a switching regulator with these characteristics on their websites) ICs that can step-down a voltage between 12 and 220 V (coming from a generator) to a ...
2
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1answer
119 views

wiring AC switch with DC led

This is a follow up to a previous question I had answered. I'd like to show the following diagram. Here, I have laid out (crudely) a diagram that has 120v-110vAC from the wall going to a push ...
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1answer
76 views

What does Boost Converter With 2-A Switch mean?

I am new to boost converter technology. All i want to know is what does switch current indicate.
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1answer
63 views

Programming undervoltage lockout in Boost(Step up) converter

Requirement is to convert 3 V (1.5 x 2 alkaline batteries) dc voltage to 5 V Dc voltage. I know battery voltage decrease with the use and i am required to set a threshold voltage so that if battery ...
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3answers
160 views

Variable voltage supply (0V , 5V, 7V, 10V, 16V) rotary switch

I need to build a variable voltage supply that can generate 0V,5V,7V,10V,16V. My idea is to use a rotary switch and zener diodes. So far I got all the outputs correct with little difference from my ...
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1answer
60 views

Dimming LED using Transistor as a Switch or as an Amplifier?

I want to try out controlling LED strip brightness/colour (via Arduino that can't supply enough power) and I understand this can be done either with using Transistor as a Switch or as an Amplifier. ...
2
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1answer
52 views

Buck regulator to match an analog voltage

In desktop computers, it's common to have headers that control fans with a 0-12V analog output, capable of up to 1A. This works fine for one or two fans, but with more than three fans, you can exceed ...
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1answer
72 views

Variable vin AC to fixed DC power supply design.. Simplest And Small

Okay, so bare with me on this one please... First post on this stack and still refreshing my memory on electronics in general. So basically i'm working on a project which generates a varying AC ...
0
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1answer
89 views

Buck converter controlled by a BJT based astable multi-vibrator with zener-based feedback?

simulate this circuit – Schematic created using CircuitLab This is my rough sketch for a buck converter controlled by a BJT based astable multi-vibrator with zener-based feedback. Before ...
0
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1answer
28 views

Why should I bother with Frequency Response calculations in a Spilt-rail buck regulator design?

I'm looking at an existing implementation a split rail step-down power supply (application report). I would like to know what's the big deal with frequency response in the reference design? I think ...
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1answer
241 views

Understanding SMPS with UC3845

Based on my previous question about IC UC3845 I want to ask about feedback in these schematic: Pin 2 on schematic above is VFB, Pin 1 is COMP, Pin3 is CURRENT SENSE. I can't define negative ...
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1answer
100 views

Power consumption when DC motor runs on battery

I have small doubt about power supply selection for a running motor. I have a small dc motor, which is rated for 12V , 3A(rated ). When the motor runs with a load 4000N, the current consumption is ...
0
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1answer
35 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
56 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 ...
0
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1answer
34 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 ...
0
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1answer
35 views

Auto electricity power switcher for two different power sources [closed]

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 ...
0
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1answer
47 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
290 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 ...
2
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1answer
81 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
61 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 ...