Easy arduino with 5v sensors and 3.3v radio?
I need to build a node which uses 5v sensors only (Ultrasonic and PIR) and want to know what the easiest way to connect a radio is.
I know that there is a adapter for the "old" through hole NRF2401+ which can be powered using 5v. But I would like to use RFM69 or smd version of NRF2401+. Is there any existing shields or adapters that could be used with a mini pro 5v or a arduino nano.
Or maybe any premade arduinos with the same features?
pir can be adapted to work at lower voltage, and there are also pir sensors working below 3 volts.
Also for ultrasonic there are some work around to make it work https://sheldondwill.wordpress.com/2014/02/04/using-an-ultrasonic-sensor-hc-sr04-with-a-3-3v-micro-controller-tiva-c-series/
If you can make it to work at 3.3 volts there are some boards in openhardware you can use with pro mini 3.3v
I use the Easy Newbie boards for most of my projects. It is designed for the nRF24L01+, and it has space for the needed 3.3v regulator if you are running it at 5V. I don't know if he has a way of using it with the RFM69 radios, but you could check. Plus it has a small proto-board area for wiring your sensors. Kudos to @sundberg84 for the design.