The Protect Nano is directed towards embedded applications that operate at fixed voltages of 3.3, 5 and 12 V, at continuous currents of up to 5 A. The over-voltage protection thresholds are set around 10% above the nominal amount, perfectly tailored for protecting ESP32 and Arduino modules from overvoltage conditions.

Fitting neatly within a standard breadboard, the Protect Nano module offers:

• Adjustable over/under voltage protection with auto-recovery (see figures for voltage levels)
• Reverse polarity (down to -12 V) and reverse current blocking
• Adjustable overcurrent circuit breaker protection (1, 3 and 6 A) that is electronically and mechanically resettable. The response time for the overcurrent protection depends on the input voltage conditions and the amount of overcurrent.
• An open-drain Power Good (PG) signal that is pulled high to Vcc if the module is allowing power through.
• Power path control by sending a 3-15 V signal to the RST pin when you want the module to be OFF, otherwise it will be on.
• Soft-start feature ramps the power input at around 1 V/ms into your circuit, turning off if the voltage input ever goes too high. This is also beneficial for reducing inrush current on start up in downstream circuits and providing a smooth turn on.
• 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.

Use individually as a protection module or several to parallel multiple supplies in a power ORing or priority power multiplexing configuration. Each module comes with terminal blocks and pin headers.

The module may be used with just pin headers, just terminal blocks, both, or soldered onto a larger PCB as a module. The KiCAD footprint for soldering onto a PCB can be sent to you upon request. Each purchase includes 2 modules.

I made this because I wanted something smaller than the original Protect module and more suited to lower voltages and lower currents. It has a lower unit cost, however you must buy 2 units in a pack.

It is a versatile unit that can be used for many different applications, and I know it will save a lot of circuits in the field from being destroyed by adjustable power supplies being used wrong or going haywire!