SparkFun LTE GNSS Breakout - SARA-R5 GPS-18031

Wireless & IoT Cellular
1

I just bought this board and want to use it with a ESP32 board and want to confirm the wiring connections. Your tutorial says:

Power Supply

The LTE GNSS Breakout is designed to accept power either over USB-C or the dedicated power pin, V EXT. The V EXT pin feeds into the 3.3V regulator which accepts a supply voltage between 3.7V to 6.0V.

Open the TXD_I, RXD_O, RTS_I and DTR/TXD2_I Solder Jumpers

LTE GNSS TXD I → RedBoard TX1 (if using Serial1) or D9 (if using SoftwareSerial)

LTE GNSS RXD O → RedBoard RX1 (if using Serial1) or D8 (if using SoftwareSerial)

LTE GNSS V_EXT → RedBoard VIN

LTE GNSS GND → RedBoard GND

q1 - usually I thought rx-tx ,tx-rx but the desc says tx-tx, rx-rx, is this correct ?

q2 - can I power the V_EXT pin with 5 V from the ESP32 USB supply? The power supply notes suggest 3.7V to 6.0V but a note I read said all inputs run at 3.3v do not connect directly yo 5v, I just wanted to make sure since this is a very expensive board.

thanks

2

q1 - I believe that’s a typo but start with those connections and if it doesn’t work, swap RX and TX.

q2 - 3.7 to 6 volts is the allowable range. Since 5 volts falls between those values, it’s OK.

1 Like
3

Thanks