Questions tagged [battery-operated]
Involving or pertaining to a circuit or device that is intended to be operated with cells or batteries (as opposed to mains power, for example).
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Charging a LiPo using Battery Protection Circuit
I have an application where I power an ESP32 from a LiPo battery. Between the LiPo and the ESP32, I have a DW01A battery protection circuit (data sheet is here: https://hmsemi.com/downfile/DW01A.PDF).
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Alkaline vs lithium vs other battery for specific use [closed]
I would like to know which type of battery would be better for a device with the following specifications:
Bluetooth access system control (BLE)
Device will have a low duty cycle, being most of the ...
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Charging two 18650 batteries separately but using them in parallel in one circuit
I want to build an external charger for 18650 batteries. I want to use the TP4056 module in order to do that. I just want to charge one single battery with that. So this charger will have a single ...
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Easiest way to combine the current from 2-3 USB-C PD ports
I'm working on a project that has about a ~100W power requirement (5v, on average 20A, which needs to run for 10 hours off of the battery); and which needs to be portable and lightweight.
I'm ...
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Selecting series resistor for a Zener diode
I am currently designing a device that will be powered by eight AA disposable batteries. For reverse polarity protection I am looking to use a P-channel MOSFET in the following configuration:
...
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Connecting sets of pc fans to a 12v battery
I am very new to electronics so please understand. I have researched but need clarity.
Basically I need to create a mock intake/outake exhaust system using recycled pc fans. Now I have to power it ...
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2
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Calculating reduction in electric car range with an additional load
I'm trying to estimate the average range reduction in mileage per hour of use of a constant electrical load within an electric car:
Assumptions (Vehicle):
$$ Usable \ vehicle \ battery \ capacity \ (...
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Feeding 12V into a powered down power supply
I have a solar battery backup system that I use when there is no power to run my transceivers. Currently, the process of switching over from the power supply's 12V power rails to the 12V output of the ...
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Two battery control
I have two Li-ion batteries in my system. (7.4 V 12000 mAh and 7.4 V 2200 mAh; also they have BMS). The larger one of the batteries can be easily removed and installed from my system, so I can charge ...
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Non-rechargeable 9V battery with diode between 12V car battery
I have a microcontroller which is powered by a car battery, voltage is stepped down to 3.3V using a voltage regulator. However if someone cuts the cord to the car battery the microcontroller has a ...
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Wire resistivity / heat generation
How to calculate the volts/amps of a battery which is connected to a simple wire for heat generation?
That is, how to use:
known wire length, diameter/area, resistivity
to calculate the required volts/...
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How do I calculate the maximum amount of current a battery can supply?
I have a few of these rechargeable batteries: http://w3.cebeo.eu/pdf_nl/4045126.pdf
I'm wondering what the maximum current this can supply is as I'm looking to connect 4 of these to power 3 servos ...
user270727
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How do I calculate required voltage and current for multiple servos?
I'm looking to power 3 servos and control them with an Arduino Uno.
Could someone please explain to me, not just specifically for this, how I can work out how much voltage and current I need to power ...
user270727
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Split current in a circuit?
I am looking to power an Arduino from a 12 V, 5 Ah lead acid battery, hooked up to a solar charge controller. (Max output: 12 V, 20 amps). I am also looking to power a Peltier Device, in order to cool ...
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Circuit Design for Peltier Cooler and Microcontroller
I Currently have a 100 Watt Solar Panel, Charging a 12v, 6Ah Lead Acid Battery using a generic solar charge controller. I am looking to connect a 12v. 6amp peltier unit, as well as a raspberry pi, to ...
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How to limit power to LED, efficiently
I am looking to use a 12V, 5 ampere car battery on a small 5V, 2A LED. Typical applications online use a resistor or voltage regulator, but since I am using a battery I would like to conserve power, ...
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Lithium Ion Cell Precharge
The IC I am using is: STNS01.
As I read, charging Lithium ion cells consists of three phases:
Precharge ("conditioning" on other articles) phase
-> Approximately 10% or 20% of fast charge ...
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2
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How does this LED last this long?
Before the end of last year, dad asked me for some small red light for his cabin, to pretend there is an alarm activated. He wanted it battery powered, so it can glow when electricity is turned off.
I ...
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Why is switching off GND instead of VCC a bad idea in battery powered application
I'm currently tasked with designing a battery-powered device (i.e. it will be connected to two four-cell LiPo batteries, each with a voltage of 14.4V to 16.8V) and am having quite a hard time finding ...
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Buck-boost converter (LTC3442) not producing output until excited
EDIT: Added datasheet for the inductor and some oscilloscope measurements.
I'm using a LTC3442 buck-boost converter from Linear Technology / Analog Devices (datasheet) in my design to produce a 3.3V ...
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Switching off an LDO to avoid damages?
Say I'm using an LDO to power an MCU such as the ATmega328p with 3.3V from 3 NiMH AA batteries.
What it isn't clear to me how to deal with brown-out situations.
I can think of 2 possible risks (i.e. ...
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LiPo cell as RTC backup battery
I am wondering what is the sensible way of using the LiPo cell that powers a handheld device to also act as the RTC backup battery for the MCU. There is charging circuitry for the LiPo cell on-board ...
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How can I get a stable 12V output from a motorcycle battery?
How can I get a stable 12VDC output from my motorcycle battery that is 12V but also connected to the alternator. When riding the bike the voltage changes anywhere between 12V and 14.5V depending on ...
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Dropping voltage from battery supply for low current application
My battery might supply 3.7 V, while absolute maximum for an IC it is supplying is 3.55 V and lowest operating voltage is 2.65 V. The IC is at sleep most of the time, consuming 10 nA. Every now and ...
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Is it possible to get 5 V at 8 A from a battery pack?
Let me first start by saying I know very little about electric circuits, so please do pardon my ignorance.
I have a Raspberry Pi project that I want to run with a battery. Ideally it would provide two ...
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Chip for power management [closed]
I am working on a project which is powered by a 24VDC power supply. My plan is to replace the 24VDC power with a battery. To make the battery last long, I am planning to auto shutdown when ...
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Help understanding audio interference from laptop when using UPS device
I have no Electrical engineering experience and would appreciate a layman's explanation on what my issue is (if possible).
My laptop battery became swollen a few months back so I removed it and have ...
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Achieving low power with Seeeduino Cortex-M0+ powered from 12V battery
I hope it's OK to cross-post this question: https://arduino.stackexchange.com/questions/88618/achieving-low-power-with-arduino-zero-clone-seeeduino-cortex-m0. I'm getting a bit desperate.
I have ...
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Calculating battery run-time to power a DC motor
I am working on designing a lithium-ion battery pack that will power a solar car that runs on a brushless DC motor. There are several pack configurations I am trying to choose between, and to do so, I ...
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Turning 24V battery to 6V battery help
I have an old RC car I'm trying to get running again. It takes a 6V 600mAh NiCd battery that has a discharge rate of 150mA but doesn't work any more. I wish to replace it with a 24V dewalt battery I ...
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How to regulate battery voltage
I am using a LiFePo4 battery 26.5 V, 18 Ah in my project where I am using three DC motors
I need a constant voltage for my motors but as the load on one of the motors increases it affects the speed of ...
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Implementing low-power variable resistance measurement
I am looking to implement a small coin cell operated circuit that uses a microcontroller, a current source and an op-amp to measure a variable resistance between 10 Ω and 1 MΩ. In order to implement ...
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Do lithium batteries regain capacity after heating up?
Every lithium battery can lose up to half of its capacity at -20C and colder temperature. My question is - will that capacity return after the battery is heated back to room temperature? Where the ...
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Grounding buck converter in a vehicle
For my test project I need to use this isolated DC converter in a vehicle, activated by relay and routed to a 6 circuit fuse block.
Can I route just the positive from relay to converter input and ...
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Best practices for low power consumption (battery operated) I2C pullups
I'm working on a battery powered device and am trying to extend battery life by using a lot of interrupt and timer driven code on the microcontroller (keeping it sleeping most of the time) and putting ...
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Better battery system
I am currently designing a battery system to support some low level electronics. The system will have both 12v and 24v electronics. I am wondering which setup would be better to get the most use out ...
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new battery, full charged capacity less than designed capacity and wear level at least 7% after drain empty
I just installed a new OEM battery to my Surface Pro 4.
The 1st-round test result is like this:
The 2nd-round test result:
The 3rd-round test result:
The 4th-round test result:
If I charge it to ...
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Adding a DC Power Adapter Socket to Sony AM/FM Radio
A friend has asked me to do a mod on their basic Sony AM/FM Radio (Model ICF306). It's 3V based but only accepts batteries. I thought about opening it up and soldering a 5.5mm Socket across the +/- ...
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Do laptops use different batteries than powerbanks [closed]
So I was researching about laptop batteries and I got confused on whether laptop batteries and other batteries like power banks are the same. To clarify I was looking at the new MacBook Pro battery ...
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2
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E-Matches ignition circuit
I am currently working on a circuit in order to ignite E-Matches such as these in order to light up the engine of an amateur rocket. In order to have control over when to actually ignite the E-Matches ...
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Why does increasing torque on DC motor in circuit affect the speed and functioning of another DC motor in the circuit?
I am working on a project in which there are system components listed below as module:
8 ultrasonic sensors 12-30 V (Sensor module)
3 DC motors (Drive module)
35 V to 5 V buck converter and a 35 V - ...
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Having battery cells in parallel does increase autonomy ? (My load is a constant power load. DC/DC)
I have 4 AA alkaline cells and I'm trying to figure out which is the best cell configuration to achieve maximum autonomy with constant power load.
I understand that if your load is a constant current ...
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2
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Measure battery voltage from a device that powers up/down periodically [duplicate]
I have a MCU that powers up periodically to log some data and then powers down (full power off -- not sleep). When powered on, it runs off a battery and I want to connect the battery to an analog pin ...
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Can battery levels ever be reliably read while it is powering an embedded system
I have an AVR microcontroller (atmega168pa) powered through two AA battery cells. When I read the battery voltage while it is not hooked up to the bread board, the voltage might read as 3.14 on a DMM. ...
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How can I connect ( and if required isolate a single module ) multiple LI-ion battery modules(with different SOCs) in parallel sharing common load
1.Need to connect two or more Li ion battery modules(having different SOC levels) in parallel with the help of bidirectional dc-dc converters sharing a common load(say 48V).
2.Isolating individual ...
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Would this LiPo 3.7v -> 3.3v schematic be feasible?
I'm basing part of my design off of another schematic. It powers an ESP32, which can pull up to around 300mA at WiFi spikes.
I am planning on using a LDO regulator to bring 3.7v LiPo voltage (then ...
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Bad capacitive touch screen sensitivity when running on battery, without earth
In short:
I´m working on a battery driven handheld device with capacitive-touch screen. The capacitive-touch works perfect when the PCB connected via USB, but it loses sensitivity when driven by ...
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Powering MCU with both battery and USB-C
I am attempting to create something resembling this. I am a total novice so I have some questions.
My questions are:
I am confused about Battery Protection IC's +5V and BAT+ parts. Is having more ...
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Li-ion battery load sharing
I'm designing a backup battery for some portable sim800 project.
In this application note, page 5 it counts problems of connecting load to battery directly.
but for example in this schematic of ...
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5
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Would retro-fitting a DC motor as the blower motor in a residential furnace be more efficient than existing 1/2 hp AC motor?
There exists DC motors of various voltages (12, 24, 48, etc) and various powers (1/2 hp, 1 hp, etc). They seem to have the necessary power and RPM to operate the blower in a conventional residential ...
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