Where power is a primary concern for the design under discussion. Use the "low-power" tag when that applies.

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0answers
38 views

Constant voltage Boost converter 12V to 26V? [on hold]

I need a DC-DC switch converter to bring a 12V input up to 26V DC output. the output will be constant Voltage if i change the load anny one have an idea ? best regards
1
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3answers
105 views

Can I increase the no of operating hours of a battery without increasing its capacity?

Setup Let's say I have a 12V / 1Ah battery pack. A device that consumes 0.1Ah will run for 10 hours. When the battery drops to 8V, the voltage will be insufficient and the device won't work anymore. ...
1
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1answer
49 views

Inverting buck-boost converter

I'm not really sure why an inverting buck-boost might be disadvantageous compared to a non-inverting converter. If the load has a particular polarity, then can't you just connect it backwards to ...
-1
votes
1answer
26 views

I have buyed a 750 rpm torque 3kg.cm motor but i am not able to calculate the amount of torque and rpm avilable on 7cm tyre

This is the motor i buyed http://www.snapdeal.com/product/core-dc-helical-geared-motor/719331155 I am working on project for science fair but it has become too much confusion that how much weight ...
2
votes
1answer
40 views

Thermocouple temperatures change drastically when my whole system is powered vs when just my arduino is powered

I apologize in advance if this should instead go in the Arduino stack exchange, but I feel it should be here. I'm using this thermocouple / amplifier pair with my Arduino Uno. I am trying to make my ...
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1answer
27 views

KiCad Multiple power inputs

I'm working on a project in KiCad. I have a connector that has multiple connections for GND, +5V, and +12V (all set to type: Power Output) in order to increase the maximum current. However, I don't ...
1
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3answers
70 views

Overpowering a peltier element

I have a peltier element rated at 15.4V, 6A, and 60 watts that I got from China and has no datasheet to be found. When I drive it with a 12 volt power supply, I can get up to about 5.5 amps giving a ...
-1
votes
1answer
28 views

access internal storage with phone shutdown (Sony Xperia S) [on hold]

I also posted this issue on Android Enthusiasts (link), and I think it could also fit in here... Long story short: (please have a look at my a more precise description in the link above) As the ...
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3answers
54 views

Power switch placement

When building a circuit, are there any conventions as to where the on/off switch should pe placed? As in between the negative pin of the battery and ground, or between the positive pin of the battery ...
-1
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0answers
37 views

switching power supply output terminal [on hold]

I have a packaged 12 volt switch-mode power supply that has 2 sets of output terminals: I wish to use it to power 5 led strips. Now, does it matter if I connect 2 led strips to one output and 3 to ...
-1
votes
2answers
29 views

Replacement power supply specs question

I have an old Philips clock radio/Bluetooth/android phone charger with a missing power supply. The device calls for 7v 2.5a with positive center tap. In my junk drawer I have a 7.5v 2.1a wall wart. ...
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0answers
27 views

Power Buffer Supply Splitter - Higher supply voltage

I'm trying to make a simple supply splitter using power buffer. See the image: But instead of LT1010 I plan to use much cheaper and more available L272 (datasheet link: ...
2
votes
2answers
71 views

DC non invasive power measurment

For one of my PhD project I have to measure power consumption from different electric wheelchairs during various tasks and recor these measurment for later studies. I have not much experience in ...
0
votes
4answers
107 views

earth as a voltage reference

Why is the neutral point of the alternator hooked up to the earth which makes all the voltages of the lines with reference to the earth. Doesn't this makes us more risky to the shocks? I think we use ...
0
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0answers
19 views

Qualcomm and phone power comsumptions

There are some links about qualcomm and phone power consumptions: http://www.notebookcheck.net/Qualcomm-Snapdragon-800-MSM8974-SoC.103706.0.html ...
2
votes
0answers
56 views

Why do adapters fail when run on inverters? [on hold]

It may be specific to my scenario, but I have brought more than a dozen adapters of varying voltages from different companies and all of them fail when powered through an inverter, after power is shut ...
1
vote
1answer
52 views

Transmit 12v power wirelessly

Is it in any way feasible, in a small form, to power a 12v light with a power source or transition source 3" away without any physical connection? ...
0
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0answers
17 views

Using (AVR) auto voltage regulator safely [on hold]

May I know if I can safely use my auto voltage regulator rated at 220 volts ac 500 watts to run an electric stove rated at 100 volts ac 650 watts?
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votes
0answers
10 views

Step load estimation/measurement in a complex circuit

Let's say you have input buck regulator that provides a system rail which is loaded by various other regulators (LDOs, switchers) which power CPU/Memory/RF systems etc, and direct loads (speaker ...
0
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0answers
47 views

PCB Power grid trace

I am currently working on my PCB layout and having trouble laying the power traces. I am trying to avoid running any tracks under signal traces and keeping power somewhat separate. I tried doing ...
0
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0answers
37 views

Compressor capacity vs input power, Kelvins law

Have got a silly confusion regarding efficiency calculation of AC & Ref. compressors. Here is a sample of specs of an Aspen miniature compressor. ...
1
vote
2answers
299 views

Designing a high-power PCB

I'm trying to build a Raspberry Pi cluster (at least 32 Pi's) and I need a convenient way to power them all. So I'd like to design a power distribution board. The distribution board will have USB ...
0
votes
1answer
25 views

Power Isolation generating error in KiCAD

I've created a ferrite bead part with two passive pins. When I insert it in a power line, it causes an error "ErrType(3): Pin connected to some others pins but no pin to drive it" Changing the pins to ...
0
votes
1answer
41 views

How to measure resource hog? [closed]

I found that bluetooth is a resource hog and that equipment drastically reduces the time between I must recharge. Can we measure how much bluetooth take? And why does it take so much resources? It is ...
-3
votes
0answers
36 views

Fixing a 600W smps/psu [closed]

I have this smps for quite some time now, it seems to be failing. It used to run my pc on full load with my gpu and now giving me random shutdowns all the time. I am pretty sure its my smps that is ...
1
vote
2answers
73 views

LM7805 followed by LD1117-3.3

The LM7805 datasheet recommends a 0.33uF cap on the input and a 0.1uF cap on the output. The LD1117-3.3 datasheet recommends a 0.1uF cap on the input and a 10uF cap on the output. I am building a ...
-1
votes
1answer
57 views

instantaneous travel

Problem 9.7 of Basic Engineering Circuit Analysis asks one to "Find the instantaneous travel supplied by the source [...]" The word "travel" does not appear anywhere else in chapter 9. I suspect it ...
0
votes
3answers
147 views

electrolytic capacitor [closed]

if i changed a 63v 1000uf electrolytic capacitor for a 35v 1000uf what would happen its a main smoothing cap on a power regulator board thats running @ 67v dc 8amp and i want to reduce the voltage ...
1
vote
1answer
41 views

How can I make an uninterrupted switch from battery to fixed power for a mobile computer?

I have a computer being powered off a Lipo battery, and I would like the ability to transfer the power supply from the Lipo to a fixed DC source (eg. power supply) without having to turn it off and ...
1
vote
1answer
59 views

bypass a low voltage shut off [closed]

Is there a way to disconnect or bypass a low voltage shutdown operation? I have a factory made electronic shooting gallery (toy) that runs on 4 AA batteries. I want to run it to a steady 6VDC supply ...
0
votes
2answers
106 views

Amps and voltage [duplicate]

I am learning about electronics and micro controllers. I started with the basics and have came to the chapter in my book about currents etc. Now, I am a little confused with voltage and amperage. Am I ...
1
vote
0answers
22 views

Cadence encounter power analysis

I have written a verilog code for a circuit (test.v) and a testbench (testd_tb.v).I use these commands for generating the power using cadence encounter RTL compiler. I have made 3 folders. ...
1
vote
1answer
84 views

Is it Possible to Produce Any Color Temperature?

I see it is possible to purchase many different color temperatures in light bulbs from 3500K (in the red spectrum) to 6500K (in blue spectrum) all the way to 10,000K and even 20,000K or higher. All ...
1
vote
1answer
65 views

How does one measure the power factor?

How does one measure the power factor? $$\text{power factor}\equiv\frac{\text{power}}{|V||I|}=\frac{R}{\sqrt{R^2+(1/\omega^2C^2)}}$$ for an RC circuit driven with \$V(t)=V_0\cos{(\omega t)}\$.
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1answer
67 views

Trace vs Plane on Multi-Layer Board

Designing a 4-layer board (signal+pwr, gnd, signal+pwr, gnd), and I have some newbie doubts about the best option to connect different connector's pin or IC's pad to power lines, or sometimes to ...
-2
votes
1answer
65 views

What circuit is used to power up a 3W LED light

What circuit should I use to power up a 3W common anode RGB LED direct from mains (220V)? I am working on a 3W rgb led which has 3 diodes connected in parallel with their + terminal as common anode. ...
0
votes
2answers
46 views

Metal Halide Bulb with Instant On?

Is it possible to produce/obtain a metal halide (MH) bulb with the possibility to turn it off and on instantly - again and again? Most MH products require 30+ minutes to restrike.. Why is this? ...
0
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0answers
18 views

How to implement a modem turn off when not in use?

Imagine a modem such as gsm-modem. I want to design a simple one just sending or receiving 1 byte of data and turn off when not in use(for power consumption). Any ideas?
0
votes
1answer
35 views

Power failure/resumption circuit

My senior colleagues and I designed a circuit to sound an alarm when mains goes off and sound another alarm when main resumes. I found two different circuits online: one for power failure detection ...
0
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2answers
46 views

Calculating Active power in 3 Phase

When calculating the active power in the 3 phase Star, and Delta formations, there are two different currents used depending on the layout. I have shown my working below, with what I have been taught. ...
0
votes
1answer
48 views

Difference between a series circuit or parallel circuit in power generation?

I wanted to know the difference between the induced-EMF and current, in a series circuit layout, vs a parallel circuit layout. In a series the current would stay the same,however, the induced-EMF ...
0
votes
0answers
12 views

Extract dynamic power Xilinx XPower

As i see in text books, Power trace of a design can be extracted using Xilinx Design Suit which show dynamic power vs. time. However trying to use Xilinx XPower and Power Estimator, it only shows ...
0
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0answers
32 views

RF-to-DC results / simulations

Can anybody point me towards simulations of, or results to the different types of RF-to-DC implementations? As in, there are different circuits such as a basic voltage doubler, etc. to achieve this. I ...
0
votes
2answers
64 views

Driving proportional valves from microcontroller

I am looking to drive a current regulated proportional (solenoid) valve that needs up to 85mA @ 24V from a microcontroller. So far I found this circuit that looks pretty straightforward: What are ...
0
votes
1answer
23 views

2600mAh Battery Charging Time

I've spent a very long time trying to work this out, but some websites seem to conflict the information - or I'm completely missing the point. I have a rechargeable battery: 2600mAh 4.2V max charge ...
3
votes
2answers
111 views

Could you submerge any electronic device (with no applied power) and see no ill effects?

In theory, could you completely submerge an electronic device in water, let it fully dry out, apply power, and see no ill effects? My logic: I can't see how how you wouldn't be able to do this. I ...
0
votes
1answer
72 views

Help with building a 3 Phase DC Motor Controller

I'm looking to design the power stage of a 3 Phase DC Motor Controller for use with the Emrax 268 motor. The maximum input battery voltage would be no higher than 300VDC and the maximum continuous ...
0
votes
1answer
56 views

Power consumption / voltage regulation

Ok so I am looking to regulate a 6v power supply down to 3v Constraints are: Extremely limited board space (no room for any IC) Must be power efficient as the module is powered by 2x button cell ...
-1
votes
1answer
60 views

AC-DC Adaptor flashes on & off

i have bought an ac-dc adaptor to power my mini-water pump. When i give power to the pump it start & goes off immediately and it's repeating like that till i plug it off. Adaptors LED is also ...
1
vote
1answer
31 views

estimating battery discharge current approximately from ac load current

I would like to know that if we have a data logger installed at a site and the logger measured the constant load current of 10 A from the Grid(Single phase@ 230 v) during a certain time say 10 am. ...