Portenta C33 + Pro 4G Module disconnects when switching 5V fan via MOSFET

Official Hardware Portenta Family Portenta CAT.M1/NB IoT GNSS Shield
1

Hello everyone,

I’m working on an IoT project and I’m facing a stability issue with the cellular connection when switching a fan load.

Hardware Setup

Board: Arduino Portenta C33
Carrier: Portenta Mid Carrier
Cellular Modem: Arduino Pro 4G Module (Global)
Actuator: Two 5V , 0.3 A DC fans
Switch: DC MOSFET switch module
Power supply:5V 2A battery

The fan is controlled using Arduino IoT Cloud .

Problem Description:

When I turn the fan ON from the cloud dashboard , the following happens:

  1. The fan turns ON correctly
  2. After turning the fan on for few seconds ,the 4G connection disconnects
  3. After a few seconds the 4G reconnects automatically

If I connect the USB cable to the computer along with the battery , everything works perfectly:

  • 4G connection remains stable
  • Fan turns ON and OFF normally
  • No disconnection occurs

But if the system runs only from the 5V 2A battery , the behavior is:

  • Device connects to 4G normally
  • When the fan is turned ON , fan runs for a few seconds
  • Then the 4G connection goes offline
  • After some time it reconnects again

Fan Switching Circuit

I replaced a relay with a MOSFET switch module .

MOSFET connections

MOSFET Pin Connection
IN PWM 5 On Portenta mid carrier
GND GND
LOAD + Both the fans red wire(+)
LOAD− Both the fans black wire (-)
Power + 5V Supply

Power- GND

I have also added 1000uF capacitor across the load, but the issue is not rectified. I would like if anyone would tell what is the issue and how to rectify it to get the required output

Thank You

2

One of these?

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Start by removing the 1000uf capacitor.
Then place a diode (1N4007) across the load.

See if the problem goes away.

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3

Without a real schematic I can only take a SWAG but to me it appears the battery impedance is not low enough. Those motors probably will draw about 3A each (10 x ) starting. Try with one fan and see if it improves. Also posting links to technical information on hardware devices helps all of us help you.

4

Still need help?

5

What is that 5V2A battery exactly?