iCufflinks improved battery life code hacking…

Scott writes

Testing is done for now. Quick synopsis (TL;DR), don’t get rid of the resistor if you want batteries to last. I tested with the full PWM values from 1-255 and then halved them to range from 1-128 (see chart 1). I quartered them as well but ended up not using it because the half ended up disappointing.

6012048606 29B575Eb88

Chart 2 shows the average current versus the resistor value for the different PWM values.

6011680363 1C71E2599C

Lastly in Chart 3, I measured the light output of the LED. If anyone cares, using a Sekonic L-508 spot meter.

6011680541 6946D32129

What this is showing is that no matter which resistor value (or no resistor) you pick when using a lower output PWM, it will never match the light output of the full range PWM values with the existing 220 ohm resistor.

Bottom line, if you want to keep the same quality of light output, you can’t change the PWM to a lower duty cycle.

Oh man this is the best post ever. LOOK AT THOSE GRAPHS! CHECK OUT THAT DATA!


8-6-2021 (August 6, 2021) is the Snakiest day of the year and it’s also this year’s CircuitPython Day! The day highlights all things CircuitPython and Python on Hardware. See you there!

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.

Join 30,000+ makers on Adafruit’s Discord channels and be part of the community! http://adafru.it/discord

Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7pm ET! To join, head over to YouTube and check out the show’s live chat – we’ll post the link there.

Join us every Wednesday night at 8pm ET for Ask an Engineer!

Follow Adafruit on Instagram for top secret new products, behinds the scenes and more https://www.instagram.com/adafruit/

CircuitPython – The easiest way to program microcontrollers – CircuitPython.org


Maker Business — Over 500,000 manufacturing jobs are going unfilled

Wearables — Stop the sweat

Electronics — Hummm… 60Hz noise in your amplifier driving you nuts?

Python for Microcontrollers — Python on Microcontrollers Newsletter: EuroPython 2021, CircuitPython 7.0.0 alpha 5 and more! #Python #Adafruit #CircuitPython @micropython @ThePSF

Adafruit IoT Monthly — Smart Agriculture, an E-Ink Newspaper, and more!

Microsoft MakeCode — MakeCode for the micro:bit - 2021 Release!

EYE on NPI — Maxim’s Himalaya uSLIC Step-Down Power Module #EyeOnNPI @maximintegrated @digikey

New Products – Adafruit Industries – Makers, hackers, artists, designers and engineers! — NEW PRODUCTS – Silicone Keycap Molds – MX Compatible Switches

Get the only spam-free daily newsletter about wearables, running a "maker business", electronic tips and more! Subscribe at AdafruitDaily.com !



1 Comment

  1. Fun investigation, cool. 🙂

Sorry, the comment form is closed at this time.