Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [low-power]

Low-power refers to electronics that are designed to use less power than their common counterparts. This is often a requirement because of limited available power, as in battery operated devices, or in cases with limited cooling capabilities, as in notebooks.

See also low-power electronics.

For the voltage in the ranges of 50–1000 V AC and 120–1500 V DC see .

931 questions
57
votes
7 answers

How can I get my atmega328 to run for a year on batteries?

Scenario I have created a nice electronic door lock for my dorm room. It is currently an Arduino Diecimila with a servo [un]locking the door. It has a numerical keypad with 3x4 buttons and 5 LED's (2 serie pairs and one single LED). It also…
Pangolin
  • 1,045
  • 4
  • 13
  • 19
39
votes
5 answers

Why does a faster clock require more power?

If you overclock a microcontroller, it gets hot. If you overclock a microcontroller, it needs more voltage. In some abstract way it makes sense: it is doing more computation, so it needs more energy (and being less than perfect, some of that energy…
Jack Schmidt
  • 2,025
  • 2
  • 18
  • 24
31
votes
7 answers

Smart ways to detect a button (less power consuming)

During a meeting for a particular project I was asked to think about the way to detect a push on a button with a MCU. The detection should consume as little power as possible. At the first glance, I thought the typical circuit with a pull-up or a…
vionyst
  • 846
  • 8
  • 16
26
votes
5 answers

Making a battery last a long time in a microcontroller circuit

I'm hoping to power an ATtiny85V for a nice long time on some small battery, probably a coin cell. I've looked into the software side, and my code is watchdog timer driven, has unused analog and digital converters turned off, the chip is running at…
Jack Schmidt
  • 2,025
  • 2
  • 18
  • 24
24
votes
5 answers

How could have Banksy kept an RF receiver running for 12 years?

I'm talking about Banksy's "Girl with balloon" painting that shredded itself at auction. I think the general consensus is that he didn't, and that it was set up before the auction (or a couple years ago, not 12 years). But lets say he did, how could…
Daffy
  • 1,151
  • 1
  • 10
  • 20
22
votes
2 answers

Some advice on charging circuit used in simple UPS

I have looked around for some way of having a 5 volt power supply that acts like a UPS. Basically want to use a micro usb connector for +5 have a battery and li-ion or other charging circuit that will maintain uninterrupted power on the output. I…
Piotr Kula
  • 2,134
  • 4
  • 21
  • 44
19
votes
4 answers

Low power micro-SD card storage

We are building a low-power data logger based upon the ATmega328P, in order to make use of the Arduino boot loader and IDE, etc. Ideally power consumption should be less than 0.3mA @ 3.3V to get around 4 months life on a single AA battery. Sensor…
geometrikal
  • 4,921
  • 2
  • 23
  • 41
19
votes
3 answers

Efficient low power regulation? i.e. 9 -> 5 Volts

For the sake providing as much current as possible to a small circuit, regulated down from ~9V to 5V (or 5V->1.5V), I have looked at some possible options. What I was originally going to do (maybe a regulator for a solar cell, or 9v battery) is the…
Hobbyist
  • 697
  • 2
  • 9
  • 16
19
votes
4 answers

Why are vias bad?

I am designing a PCB with EAGLE and saw that it was trying to limit the amount of vias through the PCB. Why do you want less vias? Why are they bad? Do they bring extra manufacturing cost or is it OK for low-frequency and low-power solutions?
rhbvkleef
  • 341
  • 2
  • 10
15
votes
1 answer

How does a smart phone measure battery percentage?

A smartphone (assume it to be an Android) usually displays the battery percentage from 0 to 100%. I am assuming that this is the usable capacity of the battery. I have several questions: How exactly does it measure the remaining capacity? Assuming…
navigator
  • 395
  • 2
  • 3
  • 7
14
votes
2 answers

Why does modulo operation consume more power?

I mainly use Cortex-M4F or Cortex-M0/0+ devices such as: STM32L4, G4 STM32L0, G0 I sometimes see blogs like this one saying "Avoid Modulo" for lower power consumption. Comparing these two programs, is this a proper way to avoid the modulo…
David Badger
  • 395
  • 3
  • 9
14
votes
7 answers

LEDs on a (battery) budget! – How can I lower the current through a LED without using up the battery?

EDIT: Here is a much brief version, the meandering motivated version is probably subsumed in the parent question on general battery life optimizations. How can I lower the current into a LED without wasting battery? I think using a resistor to…
Jack Schmidt
  • 2,025
  • 2
  • 18
  • 24
14
votes
5 answers

How to Measure Power Consumption on Extremely Low Power Devices?

This might be old news in a half a decade or two but by today's means, I am referring to electronic prototypes and designs which would draw in a μA (uA) and even nA range of current. Some recent MCUs, such as SAMD21 that I am using atm are armed…
Mehrad
  • 656
  • 2
  • 7
  • 20
14
votes
12 answers

Avoiding DC voltage drop over long distances

I am trying to power my IP camera over a long distance from the power socket (about 10m). The included power adapter, rated for 5V 2A is about 1.5m long. I cut the cable and extended it using a thicker wire (to prevent voltage drop) but despite that…
navigator
  • 395
  • 2
  • 3
  • 7
13
votes
11 answers

Low power radio + microcontroller recommendation?

I'm searching for a low power system-on-chip that combines: A processor (any achitecture) A radio (any frequency/bitrate/tx power) 2 or more I/O pins (ADC would be a bonus) Can anyone recommend a device? Which chip companies should I be looking…
Toby Jaffey
  • 28,796
  • 19
  • 96
  • 150
1
2 3
…
62 63