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Coin Cell Challenge Entries

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97 projects
468
464
1
A keychain sized gamer based on the attiny85 and a single coin cell battery.
Project Owner Contributor

TinyPong

saulSaul

17.2k
10.6k
69
A smart sensor Node to trigger an action on a smartphone each time a physical change is detected (temperature, displacement, click...)
Project Owner Contributor

Triggy - Sensor Node for Life Automation

vinchVinch

407
4
4
Small and cheap LED lights that turn on when its dark. Powered by a coin cell battery.
Project Owner Contributor

Tiny moon lights

timonskutimonsku

24k
235
216
A handheld game console programmable with (Micro/Circuit)Python.
Project Owner Contributor

µGame

dehipudeʃhipu

7.6k
95
110
Ever since I have my own company I wanted to have a PCB business card. What not add an OLED display to it?
Project Owner Contributor

Electrocard

michael-teeuwMichael Teeuw

10.7k
60
57
If you have a lot of time, you can decide your position on Earth just using watches and eyes. Or RTC and LDR.
Project Owner Contributor

Light level geolocator

jaromirsukubajaromir.sukuba

9.5k
100
85
A little UHF transmitter can be located with a directional antenna.
Project Owner Contributor

Tiny Low-Tech tracking transmitter

tomTom

9.7k
57
55
A small, cheap ($2 BOM), open source charger for LIR2032 and 20mm rechargeable coin cells built from an MCP73831.
Project Owner Contributor

LIR2032 Coin Cell Charger

jon-thomassonJon Thomasson

7.2k
5.6k
57
A charlieplexed 20 LED blinker with ATTiny45. Space efficient daisychained LED placing with shared anode/cathode soldering pads.
Project Owner Contributor

LED ring

jens-haukeJens Hauke

70k
428
416
Low power Arduino based (smart)watch
Project Owner Contributor

Chronio

maxkMax.K

324
6
12
Here I have a Maker Gummi Bear that can be worn as an electronic badge. It contains LEDs and is powered by a single coin cell battery.
Project Owner Contributor

Maker Gummi Bear

rachelRachel

29.5k
92
116
If you like happy, easy to build projects, this is not for you. This project is only for people who like to be miserable and frustrated.
Project Owner Contributor

An Unfortunate SMD Project

makersboxMakersBox

918
7
4
ESP8266 + Coin Cell + Match Box = Dash Button
Project Owner Contributor

Match Box ESP Dash Button

hagen-fritschHagen Fritsch

43.9k
199
137
Mesh of sensors, zigbee, custom RF, BT, wifi, all to MQTT Gateways on Raspberry Pi with database, dashboard and webapps.
Project Owner Contributor

Home Smart Mesh

wassimWassim

879
4
7
The business card of a common singing bird.
Project Owner Contributor

Chiffchaff Card

adam-antokAdam Antok

8.1k
97
115
An Arduino-based watch using 97 LEDs to show the time.
Project Owner Contributor

LiquidWatch

cfCF

2.3k
21
25
Atmel Attiny 85 + 6/4 RGB LEDs + analog sensor + battery 3v
Project Owner Contributor

Reactive Jeweleries

maxim-krentovskiyMaxim Krentovskiy

73
5
5
WatchMeter is a low power wrist multimeter. Very portable and intended for quick measurements and unexpected situations.
Project Owner Contributor

WatchMeter

carlos-reverbelCarlos Reverbel

760
753
6
The first digital watches had this red bubble display, you need to push a button to see the time.
Project Owner Contributor

Retro Wristwatch

saarbastlersaarbastler

1.3k
5
17
The Blinking Coin Cell Christmas Tree runs entirely off the power of a coin cell with a bit of a gravity assist.
Project Owner Contributor

Gravity Assisted Blinking Coin Cell Christmas Tree

frank-milburnFrank Milburn

5.4k
40
36
Arcade games on the Micro:bit
Project Owner Contributor

Micro:Boy

dehipudeʃhipu

950
2
3
Epaper display with Bluetooth LE connectivity
Project Owner Contributor

epaperle

pavel-sorejsPavel Sorejs

7.4k
62
53
A low cost ultra-low-power small-sized high accuracy temperature logger for use in scientific research.
Project Owner Contributor

Low-cost/power/size temperature logger

nikosNikos

2.9k
18
28
An annoying, tiny, rickrolling friend
Project Owner Contributor

ATtiny10 rickroller

shlonkinshlonkin

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