I am using a controller that is looking for 3800Hz working frequency, the magnetic pickup that has a working frequency of 380Hz. Is there a way to reduce the frequency?

 

Sounds to me as though you would want a frequency multiplier not frequency divider.

A divide by ten logic module could be designed mindful this would give a pulsed output.

You need to ask why your controller 'needs' 3800Hz and is there a workaround.

 

Yes, it would be most helpful to understand the controller and the application/usage.

Is the frequency input to the controller not configurable so that you could define 380 Hz as 100%? In other words, can you change the input scaling to percent and define 380 Hz as being equal to 100%?

Or, vice versa? Say that 100% is equal to 380 Hz?

If you could provide more details about the controller and the application (how it's being used) we might be able to offer more assistance.