I plan to make a module for my motorbike to replace fuse by current limiters and overload detection system. I've heard nice things to do with J-FET. It should work up to 12V 30AMP. The detection should return the signal to a PIC Microcontroler.
I have found the explaination below in litterature. It says that when it is overload the current falls to 8mA. Is there any ways to measure it and send a return signal to microcontroler? Thanks in advance!
JFET current Limiter
JFET current limiting circuit is shown in figure. Almost all the supply voltage therefore appears across the load. When the load current tries to increase to an excessive level (may be due to short-circuit or any other reason), the excessive load current forces the JFET into active region, where it limits the current to 8 mA. The JFET now acts as a current source and prevents excessive load current.
A manufacturer can tie the gate to the source and package the JFET as a two terminal device. This is how constant-current diodes are made. Such diodes are also called current-regulator diodes.