12
votes
Accepted
Two batteries sharing ground?
Not only can you share the grounds - sharing the grounds is required for there to be any form of meaningful circuit for signals to get around the place.
To copy-and-paste a blog post I wrote some time ...
- 105k
7
votes
Accepted
powering the arduino uno
The Arduino Uno is not really designed for that. Simply keeping the power indicator LED, regulators and extra circuits on for a week will require in the order of 1500-2000 mAh (10*24*7=1680mAh). That ...
- 7,959
7
votes
Accepted
No power from Breadboard Power Supply Module
I'm not surprised you can smell burning. You have the power supply connected backwards.
You see that little + and - symbol next to the ON/OFF jumper? That's the polarity of the two runs of pins. You ...
- 105k
7
votes
Accepted
Battery solution Nano 33 iOT
You can either use the 3.3V pin to supply power to the board, or use the Vin pin.
By using the VIN pin to power goes through a (step down) voltage regulator, that provides a nice stable 3.3V to the ...
- 11.3k
6
votes
Accepted
Powering from 3V coin cell to VCC, using I/O pin as supply GND
Can I use a I/O as (input/supply) GND?
You can use an I/O pin as a supply for another (low power) device, but
you should power the Arduino itself from its Vcc and GND pins.
I could use the reset ...
- 42.2k
6
votes
How to power an Arduino using automated mains/rechargeable battery switching?
Yes, charging a battery and supplying an Arduino at the same time is possible as long as we manage the caveats (see below) of in-circuit charging.
This is what I use:
a 3.3V Arduino (a Pro Mini in ...
- 399
5
votes
Controlling a DC motor with an external power source
Seeing as you want to use a 12V battery, you should try an external motor controller. You would essentially connect the Arduino to the controller, then the external battery and motor to the controller....
- 240
5
votes
Accepted
NodeMCU power consumption measurement and DeepSleep
An ammeter is basically a small resistor in series over which the voltage drop is measured. That resistance will play a part in the effective output impedance of your power source (battery).
This ...
- 105k
5
votes
Accepted
How to read high voltage (40-65v) from a Solar Battery bank
You need a voltage divider with resistors that have large values.
...but with all values I have tried one resistor almost melts as soon as you connect to battery.
This suggests that you have been ...
- 3,188
4
votes
powering the arduino uno
You will definitely not get a week out of a 9V cell - they have very small capacities (and are expensive relative to other types of cell).
Your Uno already has a regulator in it and this regulator ...
- 304
4
votes
Accepted
ESP8266 Battery Monitor
There are two things you need to measure the battery of the system that is doing the measuring of the battery:
An analog-to-digital converter
Some form of fixed voltage reference to compare the ...
- 105k
4
votes
Accepted
Can I power my Arduino Uno with a 9V / 990mAh battery?
While this answer addresses the specific question it should also prove useful as a link to resources relating to current reduction in other microcontroller projects.
Short:
The "C" rate for a cell ...
- 2,421
4
votes
Accepted
How do you figure out an efficient battery setup for a project?
Our beloved admin Nick Gammon has made a very neat articile on this subject, I suggest you read it and apply as many of the methods he described.
Also, it can be worth to check the requirements of ...
- 2,695
4
votes
Are any Arduino boards especially suited for low-power operation?
Technically you can use any arduino for that purpose with some modifications. I recommend to go with an arduino Pro Mini and remove the LED and the voltage regulator.
But if you don't need so much I/...
- 678
4
votes
How can I calculate remaining battery life time with arduino
you may use ADC(analogRead) to measure Li-Ion Cell voltage. unlike Ni-Cd or Ni-Mh batteries, a Li-Ion Cell Voltage is a good measure for battery status. the discharge cycle of an usual Li-Ion cell ...
4
votes
Why does using ESP8266 in deep sleep mode still drain the battery quickly?
The example shows a Sparkfun Thing, which the article notes doesn't have extra peripherals. What you show is something different, like a NodeMCU dev board, which typically has a linear regulator, ...
- 6,974
4
votes
Accepted
Powering Uno with 9v battery makes it "freak out"
Not enough current available from the battery, relays take quite a lot. As soon as the relay tries to switch the voltage drops and the Uno resets due to brownout (low voltage)
- 988
4
votes
power consumption of esp32
There's a number of things to consider when choosing batteries.
First is the capacity. In broad terms, the capacity is, mAh, means "This battery can supply X mA for one hour". So a battery of 1000mAh ...
- 105k
4
votes
Accepted
Measuring Battery level with ADC already in use
As @dandavis rightly says in the comments, you can't measure the battery voltage from a power bank. This is because the power bank typically includes a step-up converter to turn the batter voltage (3....
- 105k
4
votes
Accepted
Can I use LiFe PO4 batteries in a 18650 battery shield?
In my opinion it is NOT SAFE, if your 18650 Battery Shield also charges the battery.
Anyhow some pages state that it is possible to charge LiFePo4 batteries with 4.2V instead of the recommended 3.65V. ...
- 1,513
4
votes
Accepted
Slow WiFi reconnection after deep sleep (6 to 10 seconds)
It is in general take around 6s for the ESP to scan all the 2.4GHz Wi-Fi channels to find the SSID and the associated BSSID (i.e. Mac Address), you can eliminate the scanning time by connecting using ...
- 1,277
3
votes
How to power an Arduino using automated mains/rechargeable battery switching?
There are many ways you can do this, as you mention there are ready made shields that do this.
You need to take a few thing into consideration:
Power - how much power will your cirquit be drawing, ...
- 466
3
votes
powering the arduino uno
Three main things to do to decrease the Uno's power consumption:
Remove the power LED (you can Google for instructions if you're not sure how to do it)
Bypass the voltage regulator by providing ~5V ...
- 285
3
votes
Accepted
Barebones 328p, 2xAA vs 3xAA, which will last longer?
Yes, running at a higher voltage will consume more current. In the datasheet you have this nice graph:
I have highlighted the two voltages at 8MHz for you. At 4.5V you would typically be using about ...
- 105k
3
votes
Power Arduino from 230v with battery fallback
This kind of setup lasts around 2-3 days off a single battery.
I measured 15.8 mA consumption on my Pro Mini, running from 9V. A typical 9V battery may have a capacity of 500 mAh, so that is 500 / ...
- 37.9k
3
votes
can homemade arduino be powered up with battery?
First, of course, you'll need a battery with enough capacity, and voltage enough greater than 5v (assuming you want to run your home-built at 5v - typical, but you could run it lower, say 3.3v) to ...
- 15.1k
3
votes
Accepted
How do I power my Arduino Micro directly?
According to this schematic, VIN goes to the on arduino-micro's 5 and 3 volt regulators. So you should not need a resistor.
The 5 volt regulator needs a bit more than 5 volts at it's input to do a ...
- 7,270
3
votes
Accepted
Is it possible to charge a battery using a water flow sensor?
Is it possible to charge a battery using a water flow sensor?
No, it is basically a hall-effect sensor that requires power and generates a low effect pulse.
Look for a generator. Something like this;...
- 7,959
3
votes
Get Battery voltage on raw
No. Not directly. You can use voltage divider and measure the result with using internal reference. But it's another current consumption and you can't reduce it by (for example) entering one of the ...
- 4,742
3
votes
How do you figure out an efficient battery setup for a project?
Agreed, the DC motors would drain the 9V in no time.
Consider the other way around. The 9V powers the Arduino and the 4 AA batteries power the motor.
Then again, you probably don't need the 9V at ...
- 3,188
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