Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [coin-cell]

A coin cell (also known as a button cell) is a small round cylindrical battery. They consist of a single cell and are typically 5-20mm in diameter but often only a few millimetres thick therefore having a similar profile to a coin or button.

86 questions
42
votes
3 answers

How is wristwatch with 10 years battery life possible?

Turns out Casio offers a handful of wristwatches with "10 year battery life". The claim is that thanks to "an advanced technology" the battery life in those watches is extended to ten years. Now if you look at different models you see that they are…
sharptooth
  • 12,374
  • 26
  • 83
  • 144
19
votes
4 answers

Pulse-powering heavy loads with a coin cell

Lithium coin cells are rated for fairly low standard current draws, on the order of 1 to 5 mA. Also, while they allow greater pulsed current draws (i.e., periodic bursts), this appears to be detrimental to cell capacity (and also can cause a drop in…
boardbite
  • 4,892
  • 11
  • 47
  • 73
18
votes
9 answers

Is it safe for a CR2032 coin cell to be in an oven?

I'm designing a portable temperature logger that I would like to be able to measure temperature within my home oven. I plan on designing a mechanical enclosure to hopefully protect the design from 'frying'. Essentially I will be insulating it and I…
CongressManStan
  • 189
  • 1
  • 1
  • 3
12
votes
1 answer

How long will a DS1307 RTC run on a CR2032 coin cell battery?

I have a homemade clock based on an atmega328 and a DS1307 Real Time Clock. When off, the DS1307 is powered by a 3V CR2032 coin cell, as usual. If I leave the clock off most of the time, how long should I expect the coin cell to last? I'm aware of…
Ricardo
  • 6,134
  • 19
  • 52
  • 85
12
votes
3 answers

Low power, seven segment display

I want to display a 4 digit number on a small device that fits in a hand. I have a CR2032 3V battery at around 230mA, my microprocessor is a 8051 (in a BLE112) usually uses about 0.9µA and I want the device to last as long as possible. I've looked…
Hink
  • 123
  • 1
  • 5
7
votes
1 answer

Boosting a Lithium Coin Cell

I made a board recently and just started checking it out yesterday. I used a typical lithium coin cell and a boost converter (Microchip MCP1640). With a battery plugged in I get no voltage out of the boost converter (i.e. 5V to GND measures 0V).…
vicatcu
  • 22,499
  • 13
  • 79
  • 155
6
votes
1 answer

Coin cell battery recharging circuit for RTC backup power

I am designing a system that contains an RTC to for displaying the date and time on a user interface, as well as log events with time stamps. In this particular case, the system gets powered-on at intervals ranging from once a day to once every two…
wave.jaco
  • 655
  • 6
  • 19
6
votes
2 answers

Lithium coin cell battery showing randomness in voltage

I have a CR2032 coin cell battery and using that I am operating a BLE 4.1 module. When I connect a fresh battery in to the module the voltage shows 3.3 V, and after continuous communication with the mobile application after a few days the battery…
Viral Embedded
  • 671
  • 2
  • 7
  • 14
6
votes
4 answers

Coin cell battery retainer, problems and best practices

I use Memory Protection Devices BK-913 CR2032 Through hole battery retainer. I use Adafruit's CR2032 PCB footprint, which is almost identical to the recommended footprint in the datasheet for the retainer. It is has a square 4x4 mm center pad…
sakitten
  • 71
  • 1
  • 6
6
votes
3 answers

Lithium Button Cell Characteristics

I am working on a small wireless sensor platform and trying to figure out power supply options. My power budget is approximately: .2mA constant, ~15mA for .1s every 2-3s, and 60mA for 10s very intermittently (once or twice per hour). This works…
John Laxson
  • 63
  • 1
  • 4
5
votes
1 answer

Reliability of battery retainers for coin cells

I'm thinking of using a coin cell battery retainer on an upcoming project. The target application will be in a medium-to-high vibration environment with around 1-2 years between battery changes. Unit will be in a dust-tight enclosure. The retainer…
TimH - Codidact
  • 717
  • 1
  • 6
  • 12
5
votes
3 answers

How do I power a ATmega328 with a coin cell battery

Ok, so i am really keen to try replicate this project here I'm still a noob and my knowledge of electronics stretch as far as making a light blink using an Arduino (Maybe a bit more). I was thinking of using a ATmega328 instead of the ATtiny24A,…
Donderbos
  • 53
  • 1
  • 3
5
votes
1 answer

Protecting a coin cell from high current spikes - using a capacitor or not?

I've built some prototypes and try to gather some data from them. Skip below the two horizontal lines to read more about it. Original Question Brief summary I would like to know whether it is beneficial to add a capacitor in parallel to a CR2032…
Lightly Toasted Bun
  • 51
  • 3
4
votes
3 answers

Smallest lithium battery backup?

I'm considering putting a small lithium battery on my Super OSD Pro boards. The battery would provide power to the RTC. I am wondering how small can you get a battery? I don't really care about capacity, I expect current draw to be less than 1µA, so…
Thomas O
  • 31,546
  • 57
  • 182
  • 320
4
votes
1 answer

Is a battery's internal resistance a function of integrated current over time?

I've got a question regarding the internal resistance of a CR2032 coin cell. Here's some background info on the project I'm working on: I'm working on an electronics project in which I hope to have battery powered, more specifically I would like it…
Izzo
  • 1,984
  • 2
  • 18
  • 37
1
2 3 4 5 6