The PN Labs FlexTrip is a highly capable unidirectional electronic fuse with ideal diode functionality, working from 3-22 V at currents of up to 5 A continuous. It can be used solely as an electronic fuse, to isolate multiple supplies in parallel, or to perform power multiplexing between multiple power sources using the Power Good (PG) and Reset (RST) signals.

Its features include:

• Adjustable current levels of 0.5, 1, 2, 3, 5, 5.5 A made by soldering an onboard jumper. The response time depends on the input voltage conditions and the amount of overcurrent. Typical response times are 0.1-1.5 seconds.
• Low on-state resistance of about 37 mOhm
• Wide 3-22 V operating voltage range
• Electrical Reset (3-15 V on RST pin) and Mechanical Reset (button) available.
• an open-drain Power Good (PG) signal which is pulled up to Vcc
• Thermal Shutdown feature and on-board SMD fuse: In the event that the steady state current draw is exceeded and the board overheats, the IC has a thermal shutdown feature that will kick in around 140-150 C. Rest assured that there is also an 8 A series fuse on the module as a last resort in case a rapid power surge destroys the IC before the shutdown can respond.
• Soft-start feature: The power output gets ramped at around 1 V/ms into your circuit, which helps reduce inrush current on start up and provides a smooth turn-on.

The module can be used to perform power multiplexing/power path control by sending a signal to the reset pin to turn the module on or off. It is possible to feed the Power Good signal from one board into the reset pin of another board to create a priority power path configuration that always favors a particular supply.

I made this module because electronic fuses offer a more reliable and convenient solution than conventional fuses, but there are surprisingly few electronic fuse boards available on the market today, and if they do exist, they are not rated for low voltages like 3 V and are very expensive.

This module is sold a pack of 2, and comes with all required header pins and terminal blocks.