HI,
I have a Arduino Pro mini 5V and I am suppying the NRF24L01 VCC from the Arduino Vcc Pin , I have :
Raw:5V
VCC:~4.97V Supplying NRF24L01 VCC
GND
how it working PA_MAX when the spec say it should handle 1.9-3.6V ..
am I missing something ?
I am suppying the NRF24L01 VCC from the Arduino Vcc Pin
Then you have exceeded the maximum input voltage of 5.25V. Is it still working? The normal supply voltage should be 3V according to the data sheet.
yes it is , how possible.
I tought the voltage was from 1.9 - 3.6 per datasheet of nrf24L01
Examine your module - maybe they put a voltage regulator on it to provide the expected operating voltage, in order to make it easier to use with 5v uC's.
If not, you are using the part well outside of it's specified operating range. You should not expect the part to function correctly, though it may function correctly in some (or all) ways, or it may be unstable, or it may become permanently damaged, with or without warning. It is not surprising that the part has basic functionality intact though - many parts will function outside of their spec'ed operating range on some parameters - though potentially not within their full specified temperature range (consider the way that the '328p will usually run at 3.3v @ 16mhz, even though the data sheet says you need like 3.8 )
You really need to provide good clean 3.3V for the nRF24L01 to work reliably. An UNO does not have enough 3.3V current.
Many people have had problems running a typical nRF24L01 module on the end of jumper wires. See:
http://arduino-info.wikispaces.com/Nrf24L01-2.4GHz-HowTo
Easiest way is to use one of these neat little breakouts and plug the nRF24L01 into it. It has a good 3.3V regulator and good bypassing: See it HERE:
I've destroyed a nRF24L01 module by accidentally supplying it 5V. The SPI pins can take 5V, the VCC pin not. Like Terry says they also need a good stable 3.3V power supply. Lots of people have had problems with them because of bad power supplies.