Nano RP2040 Connect cannot connect to WiFi when powered through VIN


My two Nano RP2040 Connects cannot connect to WiFi when I am powering them through VIN
with a Schottky diode for protection) and not through USB. Using a small USB charger also works
fine. No, it has nothing to do that it waits for the (USB) Serial to start. I used the ConnectWithWPA
example and replaced all Serial with Serial1 and hooked it up to my Raspberry Pi. I see the Serial outputs for both.

Nano RP2040 Connects are running the latest firmware 1.4.8.

One Nano outputs:

Attempting to connect to WPA SSID: <MY SSID>
Attempting to connect to WPA SSID: <MY SSID>
Attempting to connect to WPA SSID: <MY SSID>

The other one just tries once and hangs afterwards:
Attempting to connect to WPA SSID: <MY SSID>

As soon as I connect USB it works for both boards:

You're connected to the networkSSID: <MY SSID>
signal strength (RSSI):-56
Encryption Type:4

IP Address: x.x.x.x
MAC address: x:x:x:x:x:x

Not sure why the behavior is different depending on how I am powering the boards. Reading the documentation both power sources should go through the power regulator.

Another thing I noticed is that the current is different when powering through VIN. When powering through USB, the Nano RP2040 Connects draw about 50mA with 5.1V. When powering through VIN, one Connect draws ~67mA with 5.2V (minus 0.2V drop for the diode). The other around 45mA.

Welcome to the forum.

Maybe your 5V power source is unsuitable. I just powered my RP2040 trough Vin and it connects fine to my network.

Radio communication tends to require large currents for short amounts of time.
You could try to add a capacitor to your power supply (place it close to the Arduino not the power supply itself if you have longer wires).


Hi Klaus,

Thank you very much. That was it.
I limited the current to 100mA on my bench power supply. That was not enough to get radio working. Increasing the limit and adding a bigger capacitor fixed it.

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