The Problem :

When working with robotics, reverse current is a common problem that can damage power supplies and control circuits. This happens when motors act like generators during sudden stops or changes in direction, pushing current back into the system.

The Solution :

To prevent this, a reverse current protection circuit is essential. The simplest method is placing a Schottky diode or a P-channel MOSFET in series with the power input. These components allow normal current flow but block harmful reverse current.

Practical Example :

Say you’ve built a small line-following robot. When it brakes suddenly, the motor generates reverse voltage. Without protection, this backflow can fry your microcontroller. By adding a P-channel MOSFET with proper orientation, you isolate your control board from damage.

Sample Calculation :

Assume your robot uses 12V and pulls 1.5A.

To prevent losses, choose a Schottky diode with low forward voltage (e.g., 0.3V):

Power loss = 0.3V × 1.5A = 0.45W (acceptable for small robots).

Recommended Products :

• P-Channel MOSFET

• Schottky Diode

Shop now at SmartXProKits.in
Support our work and India’s innovation—buy from our Make in India site!