On Jul 2, 2014, at 17:56, David Reeves <[email protected]> wrote: > That's pretty. I'll be at the space tomorrow, and happy to lend a hand with > any assembly and testing. > > Would you plan to stick to this power for the most part, or crank it higher > later?
I plan to have higher power later, or figure something else out. The issue is that we're dealing with a Chinese module that's not fully documented (no block diagram for example). The transceiver IC itself is powered at 1.8V and various low voltages, fed by a series of LDOs. I don't know the voltage of the external power amplifier. The datasheet says they recommend powering at 5V. My guess would be that the PA operates directly at 5V. 5V should be easy with USB power, but since the microcontroller is at 3.3V, we would need annoying level shifters. When we start powering things from a battery, this implies two switching regulators, one to boost to 5V, and another to buck/boost to 3.3V. Or operate everything at 3.6V, a little above the module's minimum. Or just an LDO for the 3.3V. All of these take up valuable space on the board. Konstantin is working on his own RF design using a Silicon Labs chip that's similar to the one on the module. It might be cheaper. These modules are about $10 apiece. _______________________________________________ Radio mailing list [email protected] https://list.hackmanhattan.com/listinfo/radio
