Questions tagged [power]
Electric power is the rate at which electrical energy is transferred by an electric circuit. The SI unit of power is the watt (one joule per second). Use this tag where power is a primary concern for the design under discussion. Use the "low-power" tag when that applies.
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How to get load capacitances from an FPGA design for third-party dynamic power analysis?
I would like to perform dynamic power analysis of an FPGA design outside the design tool environment. For this, I need the equivalent load capacitance of every net in the design. How can I get the ...
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More voltage for radio carrier frequency, is that all? [closed]
I soldered one radio circuit for a wave transmission with ~107 MHz frequency and I got good results. I simulated this circuit in LTSpice, too. What I have seen was that the wave got AM modulated and ...
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Can I route PWR signals under RFIC?
I am designing an RF amplifier (< 13 GHz) and want to use a board with two layers. However, the RFIC footprint (16-VFQFN Exposed Pad) has RFIN on the left, VDD on top, RFOUT on the right, and VGG ...
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Help with secondary breaker for fridge compressor [closed]
I have regular refrigerant compressor that has the standard electromechanical relay. I plan on controlling the compressor/electro relay with an ac to ac SSR. The SSR will be triggered by a 110v ...
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I am wondering if magnets can be safely used to connect power from one to the other? [closed]
I am thinking of trying to create a extension cord that can be taken apart or separated as needed. And rejoined at any length of cord but connected only through magnetic connections. So I'm wondering ...
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100 kHz Class D Amplifier with out Transfomer
I have to design a class D power amplifier, able to deliver 200 W on 50 ohm load at 100 kHz.
Power supply should be 14 or 24V, I don't know at the moment so I need an output trasformer.
I did few ...
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Low-noise/Stable power source options
This is a theoretical question. I know two sources of power as of now: SMPS (Buck/Boost Convertor) and Linear Regulator. Of these two, a linear regulator is the one with the least noise.
I would like ...
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How do I calculate or estimate how long a battery operated circuit will power an audio exciter?
I understand that this question has a lot of moving parts to it and I am quite a noob.
I have a battery operated circuit which in turn powers a planar audio exciter (such as this one: https://www....
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Asymmetric charging with (symmetric) USB C
I'm wondering if asymmetric charging behavior (does it differently depending on which orientation is used on the cable connector) is a feasible failure mode with USB C, which is supposed to be an ...
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EMI emission of the classical smartphone charger
I would like to ask you about the significance and quantity of electromagnetic interference (EMI) that produce classical mobile phone charger (transformer).
I would like to install one in a turntable ...
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How is power taken drawn from a home battery/inverter in preference to mains/grid power [closed]
I have a home battery energy storage system with some solar panels, the solar panels don't provide enough energy for me to be completely off grid (especially as I'm in the UK where the weather is ...
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How can you calculate Peak Pulse Power for a Non-Rectangular Power Pulse
I was reading this Vishay document on how Peak Pulse Power can affect resistors.
There is a flow which is attached in the document describing the process of calculating the Peak Pulse Power for a Non-...
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How does dB apply for non-linear components?
I understand that decibels are used to express power and we can use 20log(V1/V2) and 10log(P1/P2) to find the voltage and power ratios. But what are we meant to do when it comes to non-linear ...
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Max Power for a square wave on a breadboard
I am aware the max continuous power for a breadboard is 5 Watts. I am creating an amplifier circuit for a 1.7 MHz square wave using a mosfet. I would like to test it using a breadboard before I go ...
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Detect if the device is connected to a USB 2.0 or a USB 3.0 port
Is there a way for a USB 2.0 Device to detect if it is connected to a USB 2.0 or USB 3.X host port? I need this to figure out the maximum current the device can safely take.
Some more details about ...
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Japan's Maglev Train propulsion and guidance system
Above image is taken from Japan's Maglev Train youtube video by Lesics at here.
If the electromagnets along the two walls used for guidance of the train (So that it does not hit the walls) is made up ...
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How do I select the correct motors for my drone project? Suggestions? [closed]
I am currently working with my team of 3 on an autonomous quadrocopter, which can fly to an address selected by a user on a mobile using Deep Learning, GPS and sensors (LIDAR, Ultrasonic, ....).
The ...
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LED strip cable and connector sizing
I'm trying to power a LED strip. It contains 140 WS2812B with 60 LEDs/m so it is around 2.3 m. According to the datasheet, the LEDs has a 60 mA current consumption. Based on the pure math its 140*60 = ...
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PWM circuit that switches MOSFET with soft edges [closed]
I've recently bought a soldering iron from China that buzzes audibly as it heats up the tip. I'm trying to understand the reason it makes the buzzing sound and mitigate it. What I observe is that as ...
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What is this U-shaped device that seems to be connected to one leg of an overhead power line?
Seen recently in Boulder, Colorado.
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What's the meaning of RF power consumption given in mA, not in mAh?
I'm trying to understand the power consumption of an esp32 with BLE enabled and transmitting. Its datasheet provides the following table:
As you can see, it provides the power consumtions in mA. I ...
user222967
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Proper layout of GND
When designing my PCB, I noticed that all the Ground to the whole board, was passing only from a single point, which was also through a capacitor.
Is this considered bad designed, or is it negligible?...
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Soft latching power circuit stops working after heating
I implemented the below latching power circuit (can be found here https://circuitcellar.com/resources/quickbits/soft-latching-power-circuits/) that has 1 button to turn the circuit on and is turned ...
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Can this way verify whether the earth pin is grounded or floating?
I want to check whether the earth pin of the electric AC wall socket is really connected to earth. But I only have access to the socket’s phase, neutral and earth inputs.
I have no access to any known ...
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Automatic shutoff circuit without a switch
Looking at the simple automatic shutoff circuit from here
I was wondering if it is possible to modify this circuit so that instead of using a push switch, the circuit will just power off (say 250ms).
...
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X-ray power input and power output Confusion
I was looking at the power calculations of the X-ray machines and found something a bit unusual. As we know the input power must be equal to the output power. Considering an x-ray machine giving an ...
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Toroidal/cylinder single turn transformer to circular waveguide coupling
The questions is mostly in the title. Is it possible to effectively couple a toroidal/cylinder shaped ferrite core with thick spread out single turn of wire to a circular waveguide?
The idea is that ...
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What is the general rule for LDO thermal considerations at various voltages?
This question isn't so much about my specific case, but rather, I'm looking for a general rule for estimating the max current that can be pulled from heatsink-less LDOs at some voltage difference.
I ...
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Power traces in a 2 layer PCB
I have a two layer PCB, with signal traces and power traces on the top layer and a ground plane on the bottom layer. The top layer also has a ground plane extending over the space where there are no ...
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Half-Bridge inverter with IR2110, high side control signal diverges
I am designing a single-phase half-bridge inverter with SPWM modulation on LTSpice, the SPWM control signal is 10 kHz and the reference sine wave is 50 Hz.
Initially the simulation seems to work, but ...
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I tried TL431 undervoltage protection for EV battery 48V
My purpose is to make cutoff circuit that will cut battery voltage before 40 V else after 40 V it will be in working.
Above circuit I tried and it’s working fine but I'm confused because as per the ...
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Power dissipation formula
Is the below formula, present on page 26 of this buck converter correct to use?
Or should I use the formula mentioned in the 3 paragraph of this accepted answer?
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Is there any disadvantage in making a ground plane and a power plane in a 4 layer PCB?
I have read a lot of posts, forums, and application notes about why it's a bad idea to separate ground or power in mixed analog and digital circuits, so I've made a 4 layer PCB with full GND and VCC ...
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Odd bootstrap design for high-side gate drive
The above circuit utilizes a bootstrap design similar to this next illustration,
Image source: Toshiba - MOSFET Gate Driver Circuit - Application Note
I understand quite well how the capacitor C2 is ...
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What is the best way to get 5V from USB?
If we need to make a board that use two voltage levels (3.3V and 5.0V) and the board can be powered both from the USB or from an external 5V power bus, then good practice is setting a diode on the USB ...
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Smoothing Capacitor value?
I am trying to incorporate a smoothing capacitor into a power supply for a model train set. The power supply puts out 18V pulsating DC with a max of 10 amps. The train set draws an average of 5amps ...
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Why is a reverse-biased diode needed when connecting power supplies in series?
When reading application notes, I've came with the suggestion of adding reverse-based diodes across each of power supplies connected in series.
A diode in reverse bias must be added across output ...
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Parasitic Oscillations
I'm designing an LLC converter circuit. I've conducted simulations, but I have an issue. When I perform switching below the resonance frequency in the LTspice simulation, I observe parasitic ...
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Can I use the concentric conductor of NYCW 95/50 as a ground wire?
Must one buy a separate ground cable in a TN-S network for earthing or can the concentric conductor be used for earthing purposes?
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MOSFET class AB power amplifier
I'm trying to design a class AB power amplifier circuit using mosfets by biasing mosfets using current mirror and resistor (R10)
I think output voltage is correct, but the problem is that the power ...
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Brushless DC Motor -> Generator Power
I would like to know the approximate Voltage I could produce if I used this motor as a generator... If anyone could help me out with this I would greatly appreciate it!
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Why would this circuit have a "maximum" output power?
For the circuit above, in addition to what's labeled, the Zener voltage is given as Vz = 4.7V, and we have that 11.5V < Vin < 13.5V. Now, as long as the op amp is not saturated, and the Zener ...
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Is the RF/DC power on/off sequence for my simple radio beacon design good enough?
I'm using a RFPA5542 PA module. Does the power on/off sequence have to be followed exactly? Do I risk damage to the IC? I am delaying PA_EN by 2ms by an RC circuit of R13 and C5 and that is all. The ...
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What does "Power consumption max. 100 mA" mean?
I have found a lot of electronic devices with this technical specification:
"Power consumption max. 100 mA" (You can search on the net with this string and you will see a lot of matches.)
...
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What is an efficient way for distributing equal power to multiple audio amps?
I'm working on an audio system prototype that requires cables passing through active speakers in series. As cables will have different lengths, I'm counting on voltage drops along the way. Is there an ...
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Reducing power in idle loop
I'm controlling an ST32 ARM Cortex M4 via interrupts. While waiting for an interrupt, I spin in idle loop for(;;){}.
Is there a way to tell the CPU "Don't ...
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Simultaneously usage and effect on electric cost [closed]
Will using 2 watt devices simultaneously result in a higher electric bill than the same 2 if used at different times but for the same length of time (ie, 2 water fountain pumps together for 12 hours ...
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Derating of C0G DC block capacitors with applied DC voltage
I was having a discussion with a colleague at work regarding derating of MLCC capacitors when used as a DC block capacitor. My colleague mentioned that it is standard practice to derate MLCCs with the ...
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Does turn-on and turn-off delay cause MOSFET switching loss?
I know during rise time and fall time, there are MOSFET switching losses.
Is same the case with turn on and turn off delay?
I don't see any relevant pics in internet with the IDS waveform included. ...
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What does \$\mathrm{I_{D25}}\$ imply in this MOSFET datasheet?
Can someone help me in understanding the notation \$\mathrm{I_{D25}}\$ in the MOSFET datasheet?
Why is it getting multiplied by 0.5 factor?
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