In the world of USB Power Delivery (PD), reverse protection is crucial to prevent damage when the power supply is connected incorrectly. Essentially, USB PD allows higher power transfer between devices, but if the connection is reversed—say, if a device gets powered from the wrong direction—it can cause serious damage. Fortunately, this can be fixed with a simple reverse polarity protection circuit.

The Problem :

Imagine you’re prototyping a USB-powered device, and by mistake, you reverse the connections—this could burn out sensitive components. To prevent this, you can use a diode-based circuit or MOSFET to allow current to flow only in the correct direction, ensuring protection against accidental reverse connections.

Practical Example :

Suppose you’re working on a custom USB PD charger. If the polarity is reversed, it can short-circuit and damage the power supply. By adding a Schottky diode or MOSFET to your power input, the circuit will block any reverse current, safeguarding your project.

Sample Calculation:

To calculate the size of the Schottky diode to use, choose one with a forward voltage drop of less than 0.4V to minimize power loss. For example, if you’re working with 5V and need a current of 1A, the power dissipation will be:

Power = Voltage × Current
Power = 0.4V × 1A = 0.4W.
Keep this in mind when choosing your diode.

Recommended Products :

If you’re working on your reverse protection circuit, you’ll need quality components. Try MOSFET or Schottky Diodes for superior performance and reliability. Shop now at SmartXProKits.in and SmartXProKits.in.
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