New answers tagged power-supply
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Is a USB power adapter a more unstable source of power than a computer?
In short, and assuming a few things, the answer is that the computer is likely a better power supply, for your specific task.
My assumptions are:
The computer is a deskop computer and it has an ...
- 159k
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Is this circuit safe to put in my ceiling? What improvements could I make?
Finding a 600mA (or more) 5V supply with battery backup that can be safely and legally placed elsewhere in the ceiling or walls should be easy from generally trusted suppliers like Eaton or GE. Then ...
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Is this circuit safe to put in my ceiling? What improvements could I make?
Definitely not safe by any metric.
There is no fuse or other manufacturer suggested mains voltage protection circuits befoe the mains supplies.
The outputs of the supplies are shorted together without ...
- 159k
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Coupling/decoupling power supplies: how?
Not sure what this "Hi-Z" adapter device is...Maybe point to a datasheet? But in general if you are worried about multiple DC power supplies in the same circuit not having the same ground, ...
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How to correctly indicate reponse time of a power supply
Well, no idea, you don't describe your system at all -- but there are a few typical cases, and one might argue anything else is pathological and would indicate bad design of the system, anyway.
...
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How to correctly indicate reponse time of a power supply
Does the voltage drop happen exactly at the time that the current draw
is being increased?
Yes, but capacitance and inductance can make slight delays from the source to the load. In most power ...
- 84.8k
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Constant output voltage in buck-boost converters
I've tried to understand why the voltage across the inductor is constant. I think it is thanks to the generator to which the inductor is connected in parallel, and which provides constant voltage, so ...
- 17k
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Accumulate load time and retain through a power cut?
You could solve this as a programming exercise, if that’s easiest for you. If you have an Arduino (for example) that stores its runtime in non-volatile memory then it will keep track of runtime over ...
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Decoupling capacitor for drone power supply
The capacitor does not "handle rapid voltage changes". What it does do is handle rapid current changes and prevent them from becoming voltage changes. In order to pick a value, you need to ...
- 175k
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Power supply delivering more voltage than indicated even when loaded
It depends on the type of power supply. For example, an unregulated full-wave bridge supply with capacitor filtering,such as this, will charge the capacitor to 1.414 times the root-mean-square (RMS) ...
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Power supply delivering more voltage than indicated even when loaded
The most unexciting answer is that it's perfectly normal for a good old unregulated transformer supply. None of this fancy regulated linear supply or newfangled switch mode supply stuff we have these ...
- 159k
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Power Integrations Spice Model
Power Integrations website Q/A:
Spice files of ICs Posted by: atulp16 on 07/07/2020
Hi, As their is no
spice files available of ICs online. How can we get the spice files of
ICs so we can simulate ...
- 407k
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Does a power supply wear out?
Essentially all electronics have a limited lifetime. The manufacturer specifies conditions for use of the electronics – for power supplies, these are, for example, input voltage (and frequency of AC ...
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Matching power supply to a four pin connector
You’ve got a supply with positive and negative and remote voltage sense capability. The connector has four pins, so you could either connect two pins to positive and two to negative to double the ...
- 25.1k
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Does a power supply wear out?
Yes, power supplies do wear out. For example LED lamps may start blinking or don't light up because their power supply is not working any more.
Components such as electrolytic caps will degrade over ...
- 159k
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Usage of two PSU in parallel for WiFi router using Schottky diodes
What you measure is perfectly normal.
While Schottky diodes have less forward voltage drop than a standard diode, they leak current in reverse much more than a standard diode, which is what you ...
- 159k
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Do you know this circuit?
The 2 PNPs form a simple comparator; comparing the emitter voltages.
When the 3V3 level is higher than ext_3V3, the right-hand PNP will have a higher VBE than the left-hand one (since the bases are ...
- 19.4k
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Maximum power transfer with constant source power
Is this correct?
No, the only time you can get maximum power transfer is when Rm=Rl (with AC you also need to include Lm which will change the current phasor)
An infinite resistance (which would mean ...
- 84.8k
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Distribute power from one battery to multiple devices
All these components on that system, works in certain amount (range) of voltage, right?
Right.
how can I create a system - above the main system - to distribute power correctly
Do not power the ...
- 22.8k
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What are these resistors used in this flyback converter?
The resistors power the IC initially, before switching start. (After switching starts, the IC is powered by the third winding, the one at the bottom.)
Spec sheet
- 22.8k
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How to isolate RS485 (A and B) from existing transceiver? Check attached circuit diagram, is it correct?
This will be hard. You cannot know when either side has enabled transmitter and will soon transmit something on bus, you only see when something gets transmitted.
Perhaps if you know about the ...
- 159k
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How to isolate RS485 (A and B) from existing transceiver? Check attached circuit diagram, is it correct?
If I've understood your goal, you have a controller device which is half-duplex RS-485 (on the left), and a slave device, similar, on the right. The controller is not isolated, and you want it to be.
...
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Please help me identify this IC - top marking "APKZ LS23"?
It's an Intel EP53F8QI step-down converter.
(Source: aliexpress.com)
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3
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Power supply gives at most 20 millivolts
The PAB 250-0.25A has an input and an output fuse. Check the output fuse, it's a normal 1/4" x 1-1/4" type rated at 300mA.
If it is open, replace it with the same type and rating.
- 407k
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error in stlink utility
You are not supposed to use pin 19, it is not a standard to have 3.3V output.
And you need to use pin 1 to MCU VDD, or the ST-Link cannot communicate with the MCU.
So you have basically swapped pin 19 ...
- 159k
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Is it possible to build consumer-ready, non-PC modular power supplies for generic external devices?
I'm not going to answer directly your question (I don't know such a product, but haven't searched for it either), but I will explain why, in my opinion, designing such a product seems complicated :
...
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Programmable pulsed current power supply
For currents of 100mA or so, at 1kHz or less, I don't think you need much more to make that Howland-like current source work well, using almost any op-amp:
simulate this circuit – Schematic ...
- 39k
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Adding Resistor to Match Power Draw for Fan Replacement
Your calculations are correct:
If you want to draw the difference in specified currents between the two fans (0.23 - 0.06 =) 0.17 A at 12 V then the resistor should be approximately 70 Ω. And it would ...
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Programmable pulsed current power supply
Search for 'opamp current booster circuit' or 'opamp current booster schematic' (without quotes) to get dozens of examples, tutorials, and app notes. National Semiconductor (now part of Texas ...
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Programmable pulsed current power supply
Made with microcap v12.
If you want a "little" output voltage, something like this could be used ...
Output transistors are allowed to ~ 10 W out.
And here, the behavior with TIP120/TIP125 ...
- 14.5k
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Connecting Two 24VDC Power Supplies
Having multiple supplies is possible, as long as you ensure common ground and avoid any cross-feed between the Supplies.
Different question: Why not use a stronger supply to feed the whole circuit in ...
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Connecting Two 24VDC Power Supplies
It is better for you to connect both GND and make one reference GND. So you can avoid any noise in data logging part.
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Power supply for microcontroller
Microcontrollers are not like OP amps. They have a single power supply of 3.3 or 5V and a GND. Some MCUs have a maximum power supply tolerance of about 10%. Its better to consult the documentation of ...
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Power supply for microcontroller
No, because the ATMega328P MCU is not rated for 5V to 7V supply to begin with.
It is rated for 5.5V max, and it does not have to work outside nominal range of 5.5V, and absolute max rating where it ...
- 159k
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Can you help me understand W=I*V - house load
It says it's 150w, with 240v ac input and 2.5a. 2.5A * 240v = 600w - am I missing something?
Several somethings, but the big one is that the ratings you find on the labels or nameplates of most ...
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Does it matter if a fuse is on a positive or negative voltage?
One more try. Fuses will not work, but a TVS Diode will. A PSU will not generate enough fault current to operate a fuse promptly, if ever. The goal is to protect your device from overvoltages or ...
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PCB inverter design
But how to design a PCB for an inverter or power converter without
using separate power supplies for microcontrollers and gate drivers...
designing only by using input supply
Use is made of isolated ...
- 465k
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How to protect a motherboard from an old power supply?
Use one of the TVS Diodes across each rail. Once it turns on, it will clamp the voltage or die trying. Select one large enough, like 5KVA, to blow up any PSU. It costs a buck or two on Mouser.
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How to protect a motherboard from an old power supply?
A fuse at the output of a power supply, protects it from damage that could be caused by over-current or short-circuit. It definitely cannot protect the load (motherboard in this case).
'Crowbar ...
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Does it matter if a fuse is on a positive or negative voltage?
Can I use a fuse 5V 0.5A for this -5V rail as if it was 5V 0.5A?
Yes.
- 18.9k
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Does it matter if a fuse is on a positive or negative voltage?
The fuse does not care if it has + at one end or - (and the
opposite). They do care about AC vs. DC because AC has less tendency
to arc, but that is unimportant at 5V and not much more at 12V.
You ...
- 407k
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Does it matter if a fuse is on a positive or negative voltage?
A glass fuse is a passive device; it is AC/DC and swings both ways. The question is, why would you do this? You are not protecting anything. An over-current protection device (OCPD) like a fuse can ...
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Does it matter if a fuse is on a positive or negative voltage?
I have a power supply with +5 and -5 volts output. Can I use the same fuse for both of them rated 5v 2a?
Is this a bipolar power supply with +5, 0, -5 V outputs? If so, you can use the same type of ...
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Does it matter if a fuse is on a positive or negative voltage?
Yes. Fuses are non-polar.
The fuse is a thermal device.
It contains a material that melts at a relatively low temperature. The heat for the melting process comes from the current (energy) passing ...
- 12.7k
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Does it matter if a fuse is on a positive or negative voltage?
Fuses do not care about conventional agreements of people regarding positive or negative voltage.
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Is a smoothing capacitor only useful when the trace has impedance
Smoothing capacitors are only useful if the trace has enough impedance to cause a voltage drop at the load, and only really for switching loads.
If there is too much inductance in the trace/conductor ...
- 84.8k
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does rf remote transmitter power affect solenoid strength
No. The RF receiver portion of the device will simply supply a logic 1 or 0 to the circuitry controlling the solenoid. Increasing the transmitter power will only increase its range (and is illegal in ...
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Help me to identify SMD diodes marked '1DN'
The markings and package seem to match with a CITC B1DWGL-SN rectifier diode. The package is SOD-123S which seems about right from the picture.
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Help me to identify an SMD component marked 'NM' in an SOT-89 package
I think @Tony is correct, the photos match lcsc's listing for the 2SCR533P5T100 and 2SCR533PT100. The latter is NRND and the difference between the two appears to be grade related- the electrical and ...
- 407k
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Does it improve safety to make a capacitative dropper symmetric?
I'd say it makes even more unsafe for variety of reasons.
First of all, let's assume you live in a country where mains sockets and plugs are polarized and always wired correctly and there is never any ...
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