Questions tagged [power-supply]
An electronic device that supplies electrical energy to a load. It can be AC or DC input. Typically DC output.
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How to properly calculate a power supply unit for multiple analog cameras
We have acquired four Intervision-xp-964ec analog cameras for a company. They were without power supply units, just devices.
The cases of cameras says: 12V (max 420mA).
We tested them with a ...
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Can I power multiple stepper motors from a bench power supply without issue?
I'm trying to create a CNC machine as a practical implementation of what I've been learning in electronics. I want to be able to power multiple stepper motors (Nema 17s via rasp pi and driver), some ...
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Is there any small and more efficient alternative to a resistor to bring voltage down?
I am trying to sense mains to detect if some LED bulbs are ON or OFF. For that I am using HCPL-3700 (datasheet) that requires (two) resistors to reduce the voltage.
This is my schematic:
If my ...
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What is the meaning of the rated output voltage of an unregulated linear power supply?
So far I thought that when an unregulated linear power supply is rated as, say, 12V 1A, it means that when there is no load, the output voltage is 12V and the maximum safe current is 1A. Now I'm in ...
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Parallel versus series capacitor bank
I DON'T WANT THE SOLUTION
I only want to know if the question said that the capacitor bank will be connected in SERIES with the motor. Will it have the same value of capacitive reactance?
Will a ...
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Is this capacitor graph safe to be constructed?
Above is the power vs time graph of a capacitor charging & discharging in a rectifier circuit. It spikes between 350 W and -140 W, which is extremely high. However, the average is only 2.7158 W.
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Active Clamp Forward Questions
I have some questions on TI active clamp forward,
Here are my questions:
On pages 4 and 5, the document describes if the output voltage is high enough, the MOSFET on the secondary side, the energy ...
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Continuing power during 50ms power interrupt
I have a system that is powered with 3-5 VDC but there are 50ms gaps where power is interrupted and I would like the system to continue running normally when that happens. At 3.3V, the current may ...
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Could an analog synthesiser be made to run on USB power 2.5W?
5V USB is now standard and very convenient.
But I see a lot of synths and audio projects working with higher voltages ... from 9V to 12V to 22V etc.
Are there physics reasons for this? In that ...
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Do boost converters change common ground?
I am working on a project which requires the use of a boost converter to power a sensor which is read by a microcontroller. Both are powered from a battery. I know that when reading signals from a ...
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Power pack USB problem
I have a power pack with 3 5V outputs, smart usb, 5V 2A usb and 5V 1A usb. My hearing aid charger is 5V 1A. My 250 watt hour power pack shuts off in seconds if I use any of the usb ports regardless of ...
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Replace a DC jack I messed up. Can I bypass the DC jack or run from the batteries? [Sampler SP-202]
I need help to fix/replace a DC jack.
I messed it up and the board I need to fix used batteries as well but now they wont work because I butchered the DC pads.
Is there a way to bypass the DC jack and ...
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Power supply is flashing and clicking
I tried connecting the output of my 12V 5A power supply to a Peltier module (TEC1-12710) which has a maximum voltage of 12V and max current of 10 amperes. Following this, the power supply LED started ...
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What is the maximum power for an 8-pin PC PSU cable?
I have a non-modular 600W PC PSU which has one 8-wire (3 yellow, 5 black) cable split and connected to two 6+2 connectors (see the image below). I've read that according to the ATX standard, an 8 pin ...
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Joining the output of 2 different power regulators
I'm going to use a Raspberry Pi and a Pico Pi plugged together. They are both powered by the same 5V power supply (thru the 5V pins for the Raspberry, and thru VSYS for the Pico).
So far, I've used a ...
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Flyback Current Sense Resistor
Just want to make sure that I understand how the current sense resistor works in this circuit:
Basically, we want to monitor the current through the primary side of the transformer, so we know when ...
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How to size overcurrent protection?
I'm a begginer in electronics so I have some very basic questions.
I would like to protect an OpAmp power supply rails from overcurrent. But I don't know at what value I should set this protection.
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How can it be 12VDC and 1.2A 30W?
I came across a device at home which has the specs bellow written on it:
Rated Power: 30 W
Rated Voltage: DC 12 V
Current: 1200 mA
Since P = V × I, P = 12 × 1.2 = 14.4 W
Why on the specs it says 30 ...
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selecting the footprint size of ceramic capacitor for MCUs
I have noticed there are different sized(SMT foot print size) ceramics capacitor with same voltage and capacitance ratings. I have been told that smaller the footprint, smaller the parasitic ...
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Stepper motor driver TMC2209 is powered from microcontroller logic pins
I am doing my first steps with a TMC2209 V1.2 stepper motor driver and a NodeMCU.
This is my circuit:
I power the motor side via 12 V supply (12 V on the lower rails). In the circuit, this is ...
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DIY power supply [duplicate]
I am trying to build a variable power supply to replace my batteries.
The power supply should have a constant DC voltage just like batteries
maximum current will be 10mili Amps
Max voltage should be ...
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Polarity Question for Powered Home Subwoofer
I picked up a powered home subwoofer at a garage sale. It did not have its power adaptor. All it shows is 12V DC (by the symbol) 2.5A. But it does not show the polarity anywhere on the subwoofer. ...
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Problem switching boost converter using 2N2222, which turns on an RF transmitter
I am using a 2N2222 transistor to switch on and off the input supply of boost converter. The output of boost converter is powering my RF transmitter and voltage regulator which is used to provide 5V ...
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Voltage drop, current increase when two servos connected
I'm trying two design a bionic prosthetic hand adding control and movement to an open-source Thingiverse mechanical hand.
The main is to move two MG995 when a muscular contraction is performed (...
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Why the power supply of a CPU needs to have fast transient response? When the current loading of a CPU changes?
In my understanding, a CPU power supply is usually implemented by of a Point-of-load (POL) converter which is usually a buck converter. And this POL converter is required to have a fast transient ...
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Is HP 6623A Linear or Switching power supply?
I have an HP 6623A DC power supply and i wonder if its Linear or Switching power supply.
I see in the manual it says linear, but i still wonder.
Why i am asking:
I am asking this, becouse after ...
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How to create a high power buck converter power supply? [closed]
I am building a device that requires a lot of energy at its peak, about 30W.
The kind of supply I want to build looks like this:
I understand that this is made of a controller which switches a ...
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Decoupling capacitors necessary on bench power supply input on PCB?
I'm planning to power my PCB directly from a 5V and 12V bench power supply. The 5V rail will power 10+ ICs (various AND/OR logic gates, high speed comparators, and a uC). I'm estimating a max of a few ...
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Can a board like Arduino charge a Li-ion 3.7 V battery?
Some people have made Li-ion 3.7 V chargers with MCP73831 and LM358n.
The first link mentions that charging such a battery is sensitive to voltage and current:
Li-ion
batteries need to be charged ...
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Currently using two car batteries in series as filter for 24v power supply. Is it possible to connect 12v power supply to one of those batteries?
I am currently using two 12V car batteries connected in series connected to a 24V power supply (SMPS), so they act as a filter.
I need to do the same with a 12V power supply and I am not sure if to:
...
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LM338 is getting hot and stop working when we try to flow current more then 1A
I try to make a 30 V, 5 A power supply using LM338 (without heatsink) voltage regulator IC.
In my case the value of R1 is 100 Ω and R2 is 2.2 kΩ. then it gives 29.6 V as output.
when we connect a 10 ...
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Choosing the right DC-DC converter for a computer
I am looking at converting a computer to run off of a 12V battery, which means replacing its PSU with a DC-DC converter.
So, assuming that the computer is currently using 600 Watt PSU, then I assume ...
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What is the average energy loss if a booster connected to power source but without a load?
I have lipo battery 4.2V 3000mAh,
booster simulation ti power bench TPS55340QRTERQ1 ‑ 2.8V-4.2V to 8.00V @ 1.5A
Vin 2.8V - 4.2V
Vout 8v
Iout 1.5A
simulation details
efficiency 84%
1.43Mhz
duty 65%...
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What happens if a 12 V, 7 Ah battery is installed instead of a 12 V, 4 Ah battery in the Schneider APC PRO550?
I have UPS APC Pro 550 and need to change its battery. Its battery has a capacity of 21W @ 15 min-rate to 1.67 V per cell @ 25°C (77F), and what I found in local market is 7 Ah and 9 Ah.
First, I need ...
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Switching between power sources- when getting to current threshold
I would like to switch between the two power sources- solar panel and battery.
In order to avoid the Raspberry Pi restarting \ damaging (when fed from solar panel), ...
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How can I make a power system efficient and safe? [closed]
I am currently designing a power system and so far I have been using fuses before relays to protect against high current. Those relays lead to multiple loads to power. I was thinking of adding a ...
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Do data centers use single phase or 3 phase to power their infrastructure?
3 phase is more efficient than single phase for converting AC to DC; since after rectification stage the signal requires less regulation. Do some data centers use 3 phase power to take advantage of ...
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5v to 12 Power Supply
I have really no idea about electronics.
I am trying to provide IR lighting for my night camera that I use with the raspberry Pi.
The Pi is powered by a 5v usb power bank. The IR requires 12v.
I ...
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Automotive filter against voltage spikes
I am building a electric vehicle relay controller. Which controls the High voltage relays among other things. I have built an automotive power supply circuit with strong inspiration from this article: ...
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Switched power supply capacitors
Lots of electronic hardware gets problems its psu and more specificly: with the electrolytic capacitors.
How do old capacitors usually affect the capacitance of that electrolytic capacitor?
What ...
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How to make two independent voltage source from single 12V 2Amps power supply
Well, I am cranking my head around this one. I have a 5V microcontroller (AtTiny2313a-pu) which drives a 12V(max) DC motor(ampere rating unknown).
I have programmed my uC correctly and caused the ...
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How to intentionally overload almost any value resistor with a DC power supply?
When attaching a resistor to my power supply (which is a Extech 80W 3-in-1 Switching DC Power Supply, capable of 36V 5A) and the amps are set to let’s say 5A at 16V the voltage stays the same but the ...
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Isolated Power Supply Modules
I originally planned to use ISOW7841 digital isolator with Isolated power to interface part of my circuit. But Having the power and signals on one IC, is causing me problems. This is because I need to ...
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Powering my 5 volt project with AA batteries
I am thinking about using 1 AA Battery with these battery holders and this boost converter to power my 5 Volt arduino project, My project will pull about 100mA. Is there any problem with doing this? I ...
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What is this electronic component, in series (I think) with the fuse just on the input of a computer PSU?
Is similar tu a capacitor but is in series, the neutral cable of the phase is conected direct to this.. or I think is maybe after it passes the fuse...
On the board it is writen THR and on another ...
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How can I tell if power supply output is DC or AC? [closed]
I am using a Koheron SPS100 power supply and wondering wether it outputs DC or AC voltage. I also have a Klein Tools MM400 multimeter but I am fairly new to electrical engineering. How can I tell ...
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Can I switch an L78L05 with a transistor?
I need some help. I have the following circuit.
simulate this circuit – Schematic created using CircuitLab
The highlighted area is what I am having trouble with. I understand that I cannot use ...
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Adding to the output of a DC/DC Boost Converter using the same power supply as the input?
I've got a project that requires a variable output between 24-48V. This needs to be continuous-current, not PWM.
Items that I have handy from my 'box of bits', and ready to work with are: an 0.6-36V ...
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Can I still use this power supply if I clean off the rust from the transformer?
I have power supply for a vintage Timex Sinclair. The unit was sealed but the cable felt loose so I pried it open to inspect the connections. There was a knot on the other side so it was just the ...
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Two devices from a common power supply
I would like to supply two devices from a single power supply. The devices are connected to the power supply in parallel. Device1 uses a much higher current than device2. The power supply can safely ...
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