New lower price for Axon II ($78) and Axon Mote ($58).
0 Members and 1 Guest are viewing this topic.
When building this boosting regulator, I was just following the schematic on this website http://www.zen22142.zen.co.uk/Circuits/Power/boosti.htm
Other than the transistor, is the schematic correct?
And do not, I repeat do not, use a Darlington for this, it has too high a voltage drop!
Question you need to ask yoursefl... What voltage does your two batteries span over their discharge?
Quote10..33 OhmI'm confused on what this means? Switch to 33 ohm resistor?
Luckily I'm using a tip2955. This has a drop of 0.6v
You know that is a good question. I bought the batteries off Ebay from a Chinese dealer [...]
OK, they're 6 cells each, 12 cells total of the NiMH variety.NiMH cells are 1.40 to 1.45 fresh out of the charger and, with a large drain, around 0.9V when flatSo, freshly charged they're around 17V down to approx. 11V when flat.Since you need minimum 12V+2.5+0.7V=15.2V (and more likely around 1.0..1.5V more) at the input of the regulator and the fact is, that this isn't going to work for more than a tiny fraction of the available discharge, I'd recommend you to look into switching regulators, either a SEPIC or a Buck/Boost, to get a steady 12V over the full discharge.Dimension Engineering has got a couple that may work, depending on your current demand.