Updated Hardware

A project log for WorkoutAid

A Trinket powered wireless user interface for multimedia and workout tracking.

mikeneiderhausermikeneiderhauser 12/15/2014 at 22:230 Comments

I have decided that the 5V route was not the way to go. Instead, I have upgraded (downgraded?) my hardware to a 3.3V Trinket Pro @ 12MHz. This should not impact the serial communication to the RN42X. This also means that I'm changing the battery. I will now be using a 3.7V 2500mAh lipo that is much smaller (physically in size) than the USB battery pack. This should allow me to fit all of the components in and on an Altoids Tin. In addition to the battery change, I decided to add the Adafruit Trinket Pro LiPo Backpack. This backpack is a stack-able pack that adds a LiPo charger off of the bus voltage, a LiPo connector (JST?), and a header for a power switch. Why stop here! I'm also adding a Sparkfun LiPo Fuel Gauge based on the MAX17034.

Given the hardware change, I opted to rewire the entire circuit also taking into account that I had previously wired the MC14490 incorrectly in the first image. I plan to upload a schematic and updated photo of the board in the next day or so.

[EDIT 16-DEC-2014] Updated hardware (excluding the LiPo Fuel Gauge MAX17034).

To recap. Previously I was using the Trinket Pro 5V, and a 5V USB Battery pack. Now I will be using a Trinket Pro 3.3V, 3.7V LiPo, LiPo Charger, and a LiPo Fuel Gauge. NEAT!

The components list will reflect the updated hardware.