Hello, For weeks I'm bussy with my project and made very good progress. Currently I'm tweaking everything to perfection but I ran into a problem. I tried to switch two of my NRF24L01 boards for two NRF24L01+PA+LNA+SMA to get longer range. This did not work although they are wired exactly the same. My project runs on two Arduino Nano's So I decided to see if the NRF24L01+PA+LNA+SMA were actually working and not broken. I took a arduino UNO and uploaded a scan sketch which scans the whole 2.4 GHz band. Conclusion, bot NRF24L01+PA+LNA+SMA boards are working because they gave output. Then, I replaced one of my Arduino Nano's from my project with a Arduino UNO and used it with a NRF24L01+PA+LNA+SMA. Now my project worked! So, basically I debugged to a point where I don't understand it anymore. I thought
Nevermind, while writing I figured it could be a power problem.
I wired the NANO and NRF24L01+PA+LNA+SMA onto an external power supply and got it to work.
Quick conclusion: 3.3V power out from NANO is not powerful enough to power NRF24L01+PA+LNA+SMA.
I figured I still post this message because someone else might run into the same problem.
I was not able to find this problem on google so now it maybe is.
I have been working a board layout for a data logger and from what I have found, the NANO does not have a 3.3v regulator on board. visual inspection of my NANO confirms that as well.
only when power is fed into the USB port and then into the USB chip, does the USB chip output 3.3v power.
I wound up using a separate 3.3v regulator and went with a 3.3v mini for my project.
dave-in-nj:
I have been working a board layout for a data logger and from what I have found, the NANO does not have a 3.3v regulator on board. visual inspection of my NANO confirms that as well.
only when power is fed into the USB port and then into the USB chip, does the USB chip output 3.3v power.
I wound up using a separate 3.3v regulator and went with a 3.3v mini for my project.
That is incorrect. The Nano (version 3.0 anyway) does have a regulated 3.3vdc output available. However it's an internal 3.3vdc regulator built into the FTDI USB chip and has a maximum output current capacity of like 40 mA. The FTDI chip has power applied to it even if not plugged into a PC. Both the FTDI and 328P chip are powered from the same board's Vcc source.
dave-in-nj:
I have been working a board layout for a data logger and from what I have found, the NANO does not have a 3.3v regulator on board. visual inspection of my NANO confirms that as well.
only when power is fed into the USB port and then into the USB chip, does the USB chip output 3.3v power.
I wound up using a separate 3.3v regulator and went with a 3.3v mini for my project.
That is incorrect. The Nano (version 3.0 anyway) does have a regulated 3.3vdc output available. However it's an internal 3.3vdc regulator built into the FTDI USB chip and has a maximum output current capacity of like 40 mA. The FTDI chip has power applied to it even if not plugged into a PC. Both the FTDI and 328P chip are powered from the same board's Vcc source. http://arduino.cc/en/uploads/Main/ArduinoNano30Schematic.pdf
This is correct although this page incorrectly states that 3,3v is only available when connected with USB
I think you are saying that only some specific versions of the nano being sold have 3,.3v available. the Official one uses the FTDI232 chip.
the real point is about available power. the official NANO board is made by gravitech and as I stated, it does not have a 3.3v voltage regulator. the FTDI does have an internal LDO voltage regulator shown on their data sheet block diagram and they list the available power as 50mA
The MicroSD card uses 20-100mA during data transfer,
bottom line : we know that only some version have 3.3v available, but that 3.3 v is useless for power, it is only there for signals. you cannot power too many LED's or many external devices such as sensors with 50mA.
The board I am working on has 3 LED indicator lights, an RTC with the DS3231 and AT24C32 memory chip and a data logging board with a microSD card. the LED's will draw about 10mA each, the DS3231 and AT23C32 both use nano amps, but the MicroSD could use twice the available power if it was the only device connected.
Forgot to mention that I am also powering a pair of TIP-120's to control some 12V relays. only one TIP on at a time, but each controls 2 relays (parallel) relays have latching coils. so 200ms is the expected time to energize the coil.
Hi
I am also running into the same problem that the OP stated in his first post and then striked out. I am using maniacbug RF24 library with ce=9 and csn=10. With the nano connected with usb power it delivers 4.6 v as 5v on digital pins and ~3.4 v on 3.3 v on board pin, however not sure about power (you say it is 40 ma) that may be inadequate for driving the nrf24l01. Now I agree that it would not work with the onboard 3.3v pin so i decided to use external power supply. I used LM2596s based buck regulator to convert a 5v 1A (mobile charger adapter) line to 3.3v output and used that to power up the nrf module. However I did not get any success. I lost an entire day debugging the problem. I tested the nrf modules with uno and all of them ran fine with uno's on board 3.3v line.
What would be your suggestion at this point?