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Does it make sense to look into the voltage and current of the power supply for my PLC controller?

While I have used B&R in the past, I'm not familiar with this system. Reading the features list I notice, Redundancy of the CPU / X2X Link power supply possible through parallel operation of ...
Transistor's user avatar
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Does it make sense to look into the voltage and current of the power supply for my PLC controller?

While I don't work with PLC programming specifically, MCUs work similarly. They nowadays implement a low voltage detect, LVD, aka brown-out detect, BOD as standard. Back in the days some >15 years ...
Lundin's user avatar
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0 votes

Why is my simulation not loading when V2 has no current?

I see a few things wrong with the simulation, the first is the gate is floating on AD6407, this will make it difficult for the solver to determine what the sim is because of the floating gate. Add in ...
Voltage Spike's user avatar
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1 vote
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ATX power supply's "Power Good" measurement using oscilloscope

Both your measurement and the tester may be correct. And actually your numbers for pass criteria are a bit wrong. T1 is specified less than 500ms. T2 is specified more than 100ms and less than 500ms. ...
Justme's user avatar
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0 votes

Which power source is good for my project?

There are two questions here, really: how to get 8 Watts out of a mains connection how to provide a battery backup The absolutely easiest way to get 8 Watts out of a mains connection is to use a ...
Jon Watte's user avatar
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1 vote

ATX power supply's "Power Good" measurement using oscilloscope

If you trust the scope, I would use that then a power supply tester which may not have good software especially if it is cheap. If you put in a known source into the scope (like 60 or 50Hz) you could ...
Voltage Spike's user avatar
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0 votes

Power supply make static/coil whine noise when the power supply is off and the PC is off

Many depends on coils quality and operating point (electrical and so magnetical) where is core hold. Whether core is glued, how tight are winding wounded. From electrical perspective whether core is ...
Michal Podmanický's user avatar
0 votes

Power supply make static/coil whine noise when the power supply is off and the PC is off

The power button on the PC doesn't toggle everything off. The VAC to VDC conversion part of the PSU is always active until you physically pull out the wire or flip the power switch at the back of the ...
Lundin's user avatar
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0 votes

Battery failing. Oscilloscope?

I disagree with the many comments suggesting voltage logging. Spot measurements every 30s or so are not very likely to detect dropout due to high current for short duration. A cheap DSO would go a ...
danmcb's user avatar
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1 vote

Should two different DC power supply GNDs be connected to each other on a PCB?

Yes the H bridge IC references signal inputs and motor drive to same ground pin, so you must connect the 5V and 12V grounds tohether. If you connect only the 5V of the 5V supply but not the 0V of the ...
Justme's user avatar
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2 votes
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Should two different DC power supply GNDs be connected to each other on a PCB?

You would usually connect all the supplies on a single board together back to one GND. Some would suggest you seperate digital and analog grounds in sensitive systems but I don't think this applies ...
LordTeddy's user avatar
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1 vote

Why are smoothing capacitors useful/why do they work

In addition to the responses, I would like to mention something, perhaps trivial but not obvious: As mentioned: You have your battery. You have your load (speakers). Ideally, the speakers consume the ...
Makketronix's user avatar
1 vote

Why are smoothing capacitors useful/why do they work

How to explain concepts The OP's question is conceptual and requires a conceptual answer. But how do we explain concepts? Concepts are basic ideas that are generally non-electrical. Therefore, the ...
Circuit fantasist's user avatar
21 votes
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Which power source is good for my project?

The first circuit - capacitive dropper - is totally unsafe, it has a direct connection to the mains. I'm not going to comment on that circuit further, except to note that several important component ...
Neil_UK's user avatar
  • 162k
1 vote

Non-contact powering of LED indicator from a high voltage cable

You don't provide details of voltage or frequency, but given that you say "high-voltage" let's assume we're talking in the 11 kV range at 50 Hz or 60 Hz. You also don't say if the plugs are ...
colintd's user avatar
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0 votes

DC-DC Isolated converter gets really hot

First of all, this topology is poor - using a linear regulator to feed a switcher and then back to a linear regulator is bad design for the unnecessary complexity, added heat generated, and reduced ...
MOSFET's user avatar
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0 votes
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DC-DC Isolated converter gets really hot

On page 6 of the datasheet you linked, it says the efficiency drops to 35% at 10 mA. For the "few mA" current that you are drawing, the efficiency would be even lower. I would say add a ...
paki eng's user avatar
  • 648
4 votes

Why are smoothing capacitors useful/why do they work

One of the uses of capacitors is short term energy storage. For example single phase AC power goes away 100-120 times per second, so in order to make constant DC energy needs to be stored on the high ...
bobflux's user avatar
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8 votes
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Why are smoothing capacitors useful/why do they work

For your bass example, we can devise a following scenario. If you have a 1A power supply, it can't provide a peak current of 2A which an amplifier may need under heavy transient. But if you put a ...
Justme's user avatar
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2 votes
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Best way to go from 5V to .95V to power an FPGA at max 15A

Looking at the Renesas Rad Hard Switching Regulators which has been filtered to select regulators which can supply a maximum of 15 A there are the following which might meet the requirements: ...
Chester Gillon's user avatar
0 votes

AC and DC inputs to a Power Supply

to make sure that the AC source is the main primary input and the DC source is only used when the AC source is not available? The word "only" makes me consider using a relay: simulate this ...
Rohat Kılıç's user avatar
1 vote
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AC and DC inputs to a Power Supply

I suggest buying an off-the-shelf PSU to generate an isolated 420VDC from the AC supply (assuming the 12V PSU can handle 420V at its input). I suggest this because the power level is up to 1kW, which ...
Fabio Barone's user avatar
  • 1,683
2 votes

how to fix Heating issue of 7805?

Since you have an LM7805, and a 12V supply, and I assume you don't want to replace everything, I'll try to show you a fix with minimal changes. First understand that anything passing a current, with a ...
Simon Fitch's user avatar
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0 votes

How do I run four 1 watt 3.4 volt LEDs with a 5 volt 2 ampere power supply without overheating?

Put all 4 LED's in series and use a high voltage Joule Thief circuit, like this one: . The key part of this puzzle is that you don't have to run them at one Watt each. The resistor R2 takes the place ...
MicroservicesOnDDD's user avatar
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What type of connector is this - Barco/Philips TSM12PHC

I happened across this post, and don't know if you're still looking for this info, but I am working on one of these right now, and the plug is stamped 502351. I'll attach pics of the plug.
X-RAY GUY's user avatar
1 vote

Best way to go from 5V to .95V to power an FPGA at max 15A

A brief search on TI's website reveals a handful of space-rated buck controllers, several of which are capable of output voltages as low as 0.604 volts. In particular, the TPS7H4003-SEP and TPS7H4001-...
Hearth's user avatar
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0 votes

Best way to go from 5V to .95V to power an FPGA at max 15A

Develop your own buck with a rad-hard fpga as a controller. You could use an external fet that is rad hard and devleop just the spec you need and save power. At an aerospace company I used to work for ...
Voltage Spike's user avatar
  • 78k
2 votes

Best way to go from 5V to .95V to power an FPGA at max 15A

You didn't say what your 5 V current requirement is, apart from your notional concept of generating the 0.95 V 15 A supply from the 5 V supply. But I think you should generate both your 5 V and 0.95 V ...
SteveSh's user avatar
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0 votes

Charging lithium-ion battery of 3.7 V

If you manage to get your hands on some 5V relay, something like that could work, Pin6 of TP4056 gets pulled low when charging completes, you can use that to work out some load transfer logic (circuit ...
asim's user avatar
  • 568
0 votes
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Building a power supply for a Raspberry Pi 4 but having trouble with the output voltage of regulator

You are using a linear regulator (type of regulators, not the manufacturer). For a 3A output these require 3A input. And that means to have 15W output, it requires 36W in, and dissipate the remaining ...
Justme's user avatar
  • 137k
1 vote

Best way to go from 5V to .95V to power an FPGA at max 15A

I think you could coerce the PE99155 into making 0.95V by inserting a voltage divider between EAINP and VREF. Check with the Teledyne apps folks. (You did, they vetoed it.) It's also possible to ...
hacktastical's user avatar
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0 votes

Microcontroller VDD and VSS pins are shorted. Does that mean the MCU is fried?

This post is old so obviously this won't help the original poster, but I'm answering in case someone else has the same issue: You need to connect your ST-LINK VDD to the MCU's VDD. As you say, the ST-...
majegu's user avatar
  • 1
1 vote

What do I need to power a Christmas village with mains instead of batteries and in a single circuit?

If you use that circuit what will happen when you turn any of the potentiometers all the way down is the power supply will be shorted out and the pot will likely burn up. The wipers are connected to ...
GodJihyo's user avatar
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0 votes

Appropriate capacitor ratings / types for 5 V DC power supply?

The reasoning is faulty, because in reality you do not want to make a linear regulator capable of providing 2.5A. So the capacitors are irrelevant. That's because for 2.5A output at 5V which is 12.5 ...
Justme's user avatar
  • 137k
0 votes
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How to ensure a simple power sequence of a processor without a PMIC?

You can use an RC circuit as you suggested and use a comparator to release the reset once the cap reaches a crrtain voltage. You can use something like an 555 circuit for this. If you have a way of ...
DELTA12's user avatar
  • 680
1 vote

Electromagnet design and powering it up? (Fault prevention of DC supply for a small coiled Electromagnet)

This has started somewhere from the middle. You have already nailed how much space you can have per a coil. Ok, but then you should test what number of ampere turns creates the needed force effect to ...
Genwill's user avatar
1 vote
Accepted

Electromagnet design and powering it up? (Fault prevention of DC supply for a small coiled Electromagnet)

With your poor magnetic circuit - the iron core only halves the length of air that your H-field has to push flux through - you are going to need all the Ampere.Turns you can get, as it only doubles ...
Neil_UK's user avatar
  • 162k
-1 votes

Why is a capacitor connected across the power MOSFET in the DC-DC stage of most SMPSs?

The capacitor catches and changes the harmful Instantaneous Fleeting voltage by slowing it down in a controlled manner, also bringing it more closer in phase with the slower amps released from the ...
Jan Kent's user avatar
2 votes

USB C - USB A cable connection for power source

In order to get 5v out of USB-C — with no data negotiation — you have to pull the cc1 and cc2 leads low, through 5.1k resistors iirc. I just did a PCB like this, and it worked.
GaryTennyson's user avatar
4 votes
Accepted

Exploding/superhot capacitor in XT AC-DC PSU

The power supply schematic indicates this is a flyback converter, total output power rating = 80W (sum of output power rating of all rails), which is quite modest by today's standards. Your load, ...
Fabio Barone's user avatar
  • 1,683
2 votes

Exploding/superhot capacitor in XT AC-DC PSU

The circuits are unrelated in a sense, but also coupled through the flyback transformer. Both of these caps were 1000uF 16V, maybe there is a design error or manufacturing error, and cap model not ...
Justme's user avatar
  • 137k
0 votes

Does the RCD go before or after the MCB?

Typically you want to protect multiple MCB circuits with a single RCD. (For economic reasons) This dictates the RCD comes first, then the MCB and finally the cabling the MCB protects to the loads. ...
Jeroen3's user avatar
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0 votes

Philips 9 W luminaire quotes 7 A for 300 ms inrush!

All contacts in installation of LED drivers without transducer will be damaged. There are inrush current limiters to fit after the RCD-MCB device where these drivers has been installed. Inrush current ...
Bob Dok's user avatar
1 vote
Accepted

Speaker and buzzer sound levels issues

You are using a button cell battery as 3V supply for driving an 8 ohm speaker, and the CR2450 battery is not up to the task in any way. A speaker is basically 8 ohm resistance. The speaker amplifier ...
Justme's user avatar
  • 137k
0 votes

How to power servo motors?

Your current 3.7 V batteries might be inadequate in terms of voltage and capacity. Consider switching to a higher-capacity battery, like a 2S or 3S Li-ion, which can provide higher voltage and more ...
StablePSU's user avatar
11 votes
Accepted

What happens if an MCU boosts its own supply voltage while running?

I've done that with an ATtiny84 with no problems. When in sleep mode parts of the circuit (such as the analog section) are powered down and the supply voltage is dropped from 5V to 1.8V with only the ...
Kevin White's user avatar
  • 32.6k
1 vote

Need cheap variable positive/negative switching bench power supply with CC

To provide a formal answer, here is my take. For hobby use where noise and minor inconsistencies don't matter, your design will do exactly what you need it to do. I would suggest connecting a dual-...
Pxl's user avatar
  • 326
2 votes

Clock Driver - What's wrong with my H-bridge design?

Q1 dies because its gate-source voltage goes outside its limits. As you can see from the datasheet, its maximum allowed gate-source voltage is ±12V. But once you enable it, the gate-source sees -24V (...
Rohat Kılıç's user avatar
1 vote
Accepted

Using two supply rails (on supply and output pins) with 74HC595

That's not a good way of doing it. This is even said in the data sheet; outputs should not be pulled above VCC, and 70mA total current should not be exceeded, and you are doing both. If 5V supply ...
Justme's user avatar
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