TPL5110 & P-Channel MOSFET on @sparkfun SOIC to DIP 8-Pin Adapter = DIY Timer | via @PublicLab
This is a neat challenge from Public Lab user cfastie who made this cute low-power timer for data-logging projects, mounting a DIP6 IC on a DIP8 adapter, using the other adapter pads for additional connections – neat! They even mention our own TPL5110 breakout for comparison; the adapter used is already quite smaller than our own breakout size (with a few fewer features sacrificed) and they conclude they could further minify their own design using smaller resistor/s than those shown above.
Adding a low power timer to a data logger has great promise as an easy way to extend the time the logger can operate on small batteries. Rough calculations suggest that a few AA batteries can power an Arduino-based logger for a year or more when a TLP5110 timer controls the current flowing to the logger.
The Adafruit Low Power Logger costs $4.95 (plus shipping) which adds a substantial proportion to the cost of a DIY Arduino-based data logger. So I investigated making my own timer using the same components. The only components needed are the TPL5110 timer IC, a mosfet, and a resistor. Not including shipping, these cost $1.25 per set if you buy 10 of each. So I did.
One of my DIY timers was controlling a Mini Pearl Logger in my freezer the other day. A 61.9kΩ resistor set the logging interval at 12 minutes. The graph includes 10 hours of data. My freezer temperature varies a lot more than I thought it would.
Adafruit has had paid day off for voting for our team for years, if you need help getting that going for your organization, let us know – we can share how and why we did this as well as the good results. Here are some resources for voting by mail, voting in person, and some NY resources for our NY based teams as well. If there are additional resources to add, please let us know – adafruit.com/vote
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.