I am working on a project which requires three different voltage levels - Motor that can run at 7-12 V. Hall sensor that can run at 5-25 V. nRF24L01+ that can run at 2-3.6 V and AVR (arduino) which can run at 2-5 V.
Since battery life is a major concern, I think voltage regulators (specially the linear ones) will be a bad idea. For motor, I am planning to use a LiPo battery - 11.1 V rated. It'd be great if remaining circuit can be run on 3V. This way I can use AA cells for them. The only blocker is Hall sensor. I saw one which can run at 2.5-25 V but most of them run at 4.8-25V so I am not sure whether I'd be able to get low power version in local market.
As such, I am left with two choices:
- Use AA cells to get 3V which will take care of Arduino and nRF. Use boost converter to power Hall sensors.
- Use 2xAA cells to power up Arduino and nRF and another 2xAA cells added in series with the previous ones to get 6 V and use it for Hall sensor.
Which one would be a better idea?
Also, it'd be great if you can suggest me some non-latching type Hall sensors in 3 pin sil package, if possible with working voltage range starting from 1.5 or 2 volts.