SparkFun GPS Breakout NEO-M9N U.FL, Antenna, additional power source need ?

GPS/GNSS Development Boards
1

Hello,

I use the “SparkFun GPS Breakout NEO-M9N U.FL” with converter TTL to USB, with a RaspberryPi4.

So, I connect the Sparkfun on pins TX,RX,GND & 3V3.

I connect an active antenna “GPS/GNSS Magnetic Mount Antenna” (https://www.robotshop.com/uk/gps-gnss-m … m-sma.html), and it works.

Do I need to add additional power source somewhere (5V pin, or else) to benefit of this active antenna ? Or does my actual pinout be enough powerfull ?

Best regards.

2

3.3V is all you need. Supply the GPS with that and the GPS will supply power to the antenna. Your 3.3 volt power supply should be able to supply at least 100mA just to be safe.

3

Thank you.

So If I interface the SparkFun GPS Breakout NEO-M9N U.FL board with USB to TTL converter, the provided current is specified by the RaspberryPi4 USB device.

I have read, in https://www.eeweb.com/the-power-supply- … erry-pi-4/ : “Maximum total absorption of USB peripherals: 1.2 A”

Do you have some idea about ?

Best regards.

4

I don’t know anything about your adapter but the GPS needs 3.3 volt power and I/O.

The Pi should be able to supply this directly from it’s GPIO header without any issues, no need for an USB to TTL adapter.

You could still use a USB to TTL adapter but make sure it can supply 3.3 volts at 100mA and also uses 3.3 volt I/O. If you give the GPS 5 volt I/O you might destroy it.