Hi Everyone!
I have been working on a new hardware revision (v2) of the MoPower UPS and prototypes are on their way! If you are not familiar, this will be a hardware upgrade of the original UPS which you can find here:
http://www.allspectrum.com/mopower/
Here is a sneak peak at the top side of the board, which is what is visable when mounted on a Pi.
http://www.allspectrum.com/mopower/MOPO ... D-view.jpg
Some highlights of the new board..
- INA219 current sensor is available as an option measuring the voltage and current going to the Pi.
- Most of the components on the board are on the side facing the Pi.. making it possible to mount the UPS into some (possibly most) cases on the market. The CPU and lan controller area are kept clear of tall components, so most heatsinks will still fit.
- There are two switches as before. They are side activated. An optional top mounted switch is available which can act as either the power or the auxiliary switch for those who prefer it.
- There is a 20 pin GPIO on the UPS which provides: 3.3v, 5v, Input power, 4 ADCs, power and status LEDs, all three switches, and a handful of grounds and digital IO pins.
- The 5v converter is from TI, has an efficiency rating of approx 90% and is designed and tests very well up to 3.5 amps.
- Since most of the components are on the bottom of the board, a 9v block cell fits and can be easily attached to the top of the board.
- The input is capable of approx 8-30v input WITHOUT removal of the TVS diode as before, making it suitable for most 'noisy' alternator/automotive systems, both 12/14v and 24/28v.
- The battery charging circuit has improved. There are 3 charge currents which can be selected using solder bridge pads.
- Charge current is now able to be turned off, giving us the ability to detect if a battery is present or not, and saving a small bit of power as well.
- The board is capable of placing a small test load on the battery (approx 30-50ma), giving us a general indication of battery health, this may be provided as an option.
The battery charging circuit is of a constant current type.. so the new board will be suitable for most NiMH batteries as before. Several of my industrial customers seem to prefer NiMH and worldwide availability and variety of cells available is very good. I will likely keep the current sensor and test load features optional, to keep costs down for those who don't need these features. A factory supercap version, with the supercaps on board, is being investigated. A lithium version may be in the works in the future, possibly a 2 x 18650 version, but the board will likely fork to a lithium version if that happens. I anticipate all software features of the prior version will continue with version 2.
If this is something you are interested in, I welcome your questions, comments and suggestions. You can influence the features and design of the board before production release, feedback from the Pi community is invaluable to me!
Thank you!
Regards,
-Moses