No Need Adapter 🤔 WiFi Router UPS Making with Transformer | Complete Circuit Diagram

Are you tired of internet disconnection every time the electricity goes off? Don’t worry! Today I will show you how to make a WiFi Router UPS (Uninterrupted Power Supply) using a Transformer, and the best part is – No Extra Adapter Needed! 🚀

This DIY UPS will automatically switch between AC mains and battery backup, ensuring your WiFi Router, ONU, or Modem keeps running smoothly during power cuts. Let’s dive into the details step by step.

🔋 Why Do You Need a WiFi Router UPS?

1. Keeps your internet running 24/7, even during load-shedding.
2. Protects sensitive devices from sudden power loss.
3. Cost-effective DIY project (under low budget).
4. No need to purchase expensive branded router UPS.

⚡ Working Principle of Transformer-Based WiFi Router UPS

1. This circuit uses a Step-Down Transformer, Rectifier, Battery, and Automatic Changeover System.
2. The transformer converts AC 220V into DC supply.
3. Diodes and capacitors filter the voltage.
4. A battery stores backup power.
5. MOSFET + Diode arrangement automatically switches between mains and battery without interruption.
6. A DC-DC regulator provides a stable 5V/9V output for your WiFi Router.

👉 That means, when electricity is present, the router runs on AC supply and charges the battery. But when the power goes off, the battery instantly takes over – ensuring Zero Downtime Internet.

🛠 Components List (Step by Step)

1. To build this project, you will need:
2. Transformer (AC to 12V DC)
3. Bridge Rectifier (6A10 diodes x4)
4. Filter Capacitors (1000µF, 220µF, 470µF)
5. MOSFET IRF9540
6. Schottky Diodes (1N5822)
7. Voltage Regulators (LM2596, XL6009)
8. Inductors (470µH)
9. Resistors (10kΩ, 330Ω, 220Ω, 1kΩ)
10. Switches (SW1, SW2, SW3)
11. LED Indicator
12. Rechargeable Battery (Li-ion or LiFePO4 recommended)

📐 Circuit Diagram Explanation

The circuit has three main sections:

1️⃣ Power Input & Rectifier

AC mains enter through the transformer.

4x 6A10 diodes form a bridge rectifier.

Capacitors smooth the DC supply.

2️⃣ Battery Charging & Auto Changeover

MOSFET IRF9540 works as an automatic switch.

Diodes (1N5822) prevent reverse current.

When mains are present → Router runs on AC and battery charges.

When mains fail → Battery power flows instantly.

3️⃣ Voltage Regulation

LM2596 & XL6009 DC-DC converters provide stable 5V / 9V / 12V outputs.

Suitable for different WiFi Router and ONU models.

LED indicator shows UPS activity.

🖥 Output & Testing

1. Connect your WiFi Router/ONU to the output terminals.
2. Test with mains ON → Router runs normally, battery charging.
3. Test with mains OFF → Router instantly runs on battery.
4. No adapter needed, no internet disconnection! 🎉

✅ Advantages of This WiFi Router UPS

1. Zero Switching Delay → Internet never drops.
2. No Adapter Required → Transformer powers everything.
3. Cost-Effective → Cheap DIY solution.
4. Expandable → Can run multiple devices with higher battery capacity.

📌 Video Reference:

🎯 Final Words

This DIY WiFi Router UPS with Transformer is a perfect project for those who face frequent power cuts but don’t want to lose internet connectivity. With simple components and an easy circuit, you can keep your router alive without any external adapter.