How to keep the backlight on on the keyboard?

[beto53]

Hello! Could you help me, please?

My notebook is a Dell Latitude 3540.
I'm using Linux Mint 21.3 XFCE
Kernel 6.5.0-26

When I type, the keyboard backlight turns on, but turns off after 10 seconds of inactivity.

I've already tried using the Fn + F5 keys. They "work", alternating between "off", "low light" and "high light". However, whatever the setting, the keyboard light turns off after 10 seconds.

How do I keep the keyboard backlight active?

Thanks!