⚠️ The Problem

In many battery-powered or solar-powered systems, power sources fluctuate. When input voltage dips close to the SMPS output voltage, traditional designs fail or shut down. This issue is called low-voltage dropout, and it can crash your circuit unexpectedly.

✅ The Solution

To fix this, design your SMPS with components that support low dropout operation. This includes using high-efficiency synchronous rectifier MOSFETs instead of diodes, and selecting controllers that operate down to 0.8V difference between input and output.

🧰 Practical Example

Say you’re powering a 5V microcontroller system using a 6V battery. If the battery drops to 5.3V under load, a poorly designed SMPS will shut down. Using low Rds(on) MOSFETs helps maintain output even at minimal voltage gaps.

📐 Sample Calculation

Let’s say your MOSFET has Rds(on) = 25mΩ and current draw is 2A:

Voltage drop = I² × R = (2)² × 0.025 = 0.1V

So with 5.3V input, you still get ~5.2V output—enough to keep your system running!

🛒 Product Recommendation

Upgrade your SMPS with reliable, Made in India parts:

• Synchronous MOSFETs

• [Switching Controllers]

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