I made a circuit that gets power from an external 12v power supply. Since the nrf works off of 3v3 i put a 3v3 voltage regulator (lm1117) and i feed the nrf its output. The + side of the 12v rail goes directly to the arduino. I usually have the 12v power off and have the usb power the arduino while i was programming it. Then i planned to connect the 12v supply and check the circuit out through the usb serial port. When i followed my steps ı saw that the nrf wasn't working (it wasn't a dud as i had used earlier) and the mosi and sck pins seemed to be shorted out to each other. Also the nrf was drawing around 100 mA at that dead state it was in. My guess is that either i had the supply connected bacwards at one point and since i had no backwards polarity protection i fried the chip (the arduino was fine though) or the arduino somehow backfed through the vin pin and fried the nrf (but there was a regulator in between). If anyone can help i'd be appreciated.
Please post the schematic of your circuit.
Can't open it, use jpeg
lm317 MABTG - data sheet does not specify it is 3.3V, measure voltage on pin #2, you may have oscillation, add 100uF on pon #2.
google - voltage regulator 3.3v
Before connecting regulator to any thing check that you have 3.3V
you can use 3.3V from arduino
Thanks for the help. The lm317 on the schematic is just a placeholder as i couldn't find an lm1117 with the to220 format on the program. As for the capacitors i tried this circuit out on a breadboard before it worked just fine. I checked the output of the regulator and it was 3.6v which should be fine. I hesitated to use the arduino's 3.3v regulator as i feared that it may exceed the maximum current rating of it. (The nrf on the schematic is also a placeholder. I use the one with the sma antenna)
It is not clear what you are actually doing, limit the current which is drawing by nrf , feed it through resistor, start with 100 ohm and go with lower resistance up to 10 ohm,
What current consumption is it by specificatin ?, also measure it.