Questions tagged [low-battery]
The low-battery tag has no usage guidance.
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Embedded device with Hardware issues consisting atmega 328p, RFM96 and ADXL345
I have a device that works on 3V battery (2 D size cells) now I want to debug it so that all the devices work correctly. My device consist of atmega 328p, running on 08 MHz Crystal which gets readings ...
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3
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Simple circuit to bypass preamp when battery fails
A guitar has an on-board battery powered pre-amp between the pickups and the output jack. This is great until the battery fails, when it goes dead until the battery is replaced.
I would like to have a ...
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Best way to halve 12V battery voltage for 6V device, while still being able to measure the battery level?
I have a device that is powered by 4 AA (4x1.5V=6V) batteries, but I want to power it with a 12V battery.
The device measures its input voltage to determine the battery level. I only need to know if ...
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Troubleshooting a Low Voltage Cutoff (LVC) Circuit for Overdraining Prevention
I am attempting to design a Low Voltage Cutoff (LVC) circuit to safeguard against overdraining my 12V rechargeable battery. The objective is to halt circuit power once the battery voltage drops below ...
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2
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Unpowered LM393 Comparators
I'm working on a battery powered device and would like an LED to come on when the battery is getting low. In the given schematic, the LED is a red LED having a forward voltage of 2V, Lite-On product ...
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MSP430FR4133 Low Battery Voltage Periodic Monitoring
Here is the code I used to configure and monitor my voltage that when it becomes 1.2V, BATTERY_ON symbol on my LCD is ON. The checking of voltage is every 10 seconds. This code below works using ...
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Why would a battery pack read as a lower voltage before being disconnected from device, then read as a higher voltage after [duplicate]
I'm working on a device that uses a proximity sensor to count the number of times something passes through its field of view at a certain distance. It is connected to an Arduino Nano and a battery ...
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Electric guitar with active electronics and a DIY battery gauge
There is a primitive DIY battery charge monitor which blinks a LED after input voltage drops lower a certain level. Let's call it battery gauge. Also, there is an electric guitar with active ...
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RTC UPS power cycle on low battery
My RTC UPS switches on and off the whole time when the battery is low.
I think it could be with the voltage monitor circuit as with the led indicator on the ups it shows the ups's battery voltage is ...
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Are there any substitutions for depletion PMOS transistors?
I am currently building a low-voltage cut-off circuit. When the battery is under 10 V, the microcontroller should pull the battery power to ground which will blow the fuse with high current and cut ...
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When is it time to change out batteries in multimeters?
On my multimeter, the D.C. voltage readings get inaccurate over time due to battery discharge.
How can I tell when to change out the batteries?
By consulting the manuals, I found what is displayed ...
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Ultra-low power low battery disconnect circuit
I am trying to design a circuit to replicate the behavior of the LTC4071 battery charger/protector IC (see datasheet here). In particular I want to replicate the low battery disconnect function which ...
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Single-cell lithium battery powered comparator circuit with hysteresis
I recently was reviewing a circuit I made and began to question its feasibility. The circuit cuts off a battery's connection to a load after the voltage has fallen below a certain threshold.
To ...
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Trinket M0 - Using USB serial out when running on battery
I am using a Trinket M0 for navigation lights on an electric R/C plane. I thought it would be useful to also use it to monitor my LiPo voltage so I know if it is safe for another flight. For debugging,...
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Voltage of 3 V batteries [closed]
I ordered 3 V CR2 batteries. Actually they are 2.92 V and 2.93 V.
Should I consider them faulty, or is this difference from the nominal voltage acceptable?
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Low-voltage shut-down compatible with deep sleep in a battery-operated ESP32
I'm designing a battery-operated device driven by an S2 mini board, which is based on an ESP32-S2 microcontroller. In order to save battery the board wakes up every 15 mn, does its thing, and then ...
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What would prevent a new AGM battery from fully charging?
What can prevent a new out-of-the-box AGM battery from fully charging, given that neither age nor sulphation are factors?
Specifically, one of the six cells in my brand new Parts Unlimited battery is ...
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Cheapest way to detect low voltage of a battery
I have 29V battery which drops to 24V at about 30% capacity.
I want to detect when the battery goes lower than 24V and generate a 12V signal. (I have 12V auxiliary supply for lights etc)
Since I'm ...
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Dual cell protection using DW01
I am using GS7001B-84 dual cell charger to charge battery. Now I want to protect these two cells. I have DW01 battery protection IC and AP2302B N channel mosfet. How can I protect battery using these ...
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Relay Buzzer Circuit
I'm trying to set up a circuit to protect a battery in a battery box, using some parts I had lying around. Its job is to open the primary relay (load/charging) and sound a buzzer when the supply drops ...
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Can we use Zener diode as battery low voltage cut off?
Suppose we have 150 watt and 300 watts portable photovoltaic system with 13.5V battery (50Ah) and we want the low voltage cut off point to be set at 10V.
Can we achieve this simply by using zener ...
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568
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Wake up MCU with radio signal using a battery
Currently I have a project that runs with the chip from Arduino (Atmega328p).
This is what it does:
It wakes up.
Powers the NRF24L01 module. And it configures it to only send one packet
...
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Under what conditions does a p-FET gate have to be at a higher voltage (or more negative) than its source?
Is there a general rule for p-FET's that explains when Vg can can be higher (or more negative) than Vs? I had posted a while back and a helpful person explained I needed to keep Vgs higher than Vds, ...
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12 V, 7 Ah SLA battery reads 0 (zero) volts
I have a new 12 V, 7 Ah battery which reads 0 (zero) vokts. Let me explain the situation. I have a 800W UPS (for pc) whose battery wasn't giving enough backup. So I decided to replace the battery. I ...
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Battery Charger Cut off
I need to confirm that this circuit will protect battery against over charging or not.
https://bestengineeringprojects.com/12v-7ah-smart-battery-charger-with-pcb-diagram/
Which is better circuit for ...
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3
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2
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390
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Why does this lithium battery have such a flat discharge curve?
I'm trying to understand some apparently anomalous observations of the discharge profile of a 1S lithium battery. I'm using this battery to run a Raspberry Pi Zero W, back-powering the Pi via the +5V ...
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How to estimate Li-ion battery health for an unused smartphone? [closed]
I am considering purchasing a new smartphone that is several years old and could use a little electrical engineering help from the EE geniuses here.
I've performed quite a bit of research, and found ...
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Questions about Li-Ion batteries
I am working on integrating single 4.2V Lithium battery(400mAh capacity), charger IC, and battery fuel gauge for an embedded project.
I have watched several TI training videos about battery management,...
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Li-ion vs Li-Po batteries cut-off protection
I am confused with the differences between Li-ion batteries (like 18650) and Li-Po (the flat ones).
I know that basically they are both lithium ion, but when I want to buy I see that LiPos have always ...
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Running a 12v fridge and protecting the battery from low voltage
I want to run a 12V (65W) fridge from a battery circuit on a boat. However, I want to protect the battery from being drained and potentially damaged by the fridge if the voltage drops too low so I ...
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