How to Make a Circuit Diagram from Scratch in EasyEDA

Today, we are going to design a circuit from scratch, and I will show the whole process of designing a schematic. What precautions and design strategies can you follow in EasyEDA to make your PCB look professional good.  We are designing a battery charger board, which comes in moderate difficulty. In this design, we will first go through the datasheet and choose the components that are required, and then design the actual circuit with some logic. I’ll walk you through my own design process for a CN3058E-based LiFePO₄ battery charger with protection, from the initial idea to a finished schematic and PCB, all created in EasyEDA.

Introduction to EasyEDA

When it comes to designing electronic circuits, one of the most popular online tools is EasyEDA. This free, cloud-based platform allows engineers, hobbyists, and students to create circuit diagrams, run simulations, and even design printed circuit boards (PCBs) — all within a web browser.

Unlike traditional software that requires installation, EasyEDA works online, making collaboration and project sharing much simpler. Whether you’re a beginner experimenting with Arduino projects or a professional preparing for PCB production, EasyEDA provides an easy entry point.

What is EasyEDA and Why Use it?

EasyEDA is an integrated design environment that supports:

• Schematic Capture – draw your circuit diagram from scratch.
• Circuit Simulation – test your design virtually before building hardware.
• PCB Layout – turn your schematic into a PCB design.
• One-Click Manufacturing – directly order boards from JLCPCB.

Key benefits include:

• Free to use with paid advanced options.
• Accessible anywhere with an internet connection.
• Large component libraries.
• Seamless PCB ordering and assembly integration.

How to Make a Circuit Diagram from Scratch in EasyEDA - Using CN3058E as an Example

The CN3058E is a linear battery charger IC optimized for 3.6V/3.7V LiFePO₄ cells. From the datasheet, I have gathered information on the charging profile Constant-Current / Constant-Voltage (CC/CV). It comes in an 8-pin package, and through an external resistor, we can set the charging current. Because the package is small, so does not bear much heat, so we have to keep it below the maximum range of 1A. Moreover over we find some status indicators for charging and full charge, and battery temperature monitoring. The circuit diagram shown in the datasheet is given above for reference. I do make some changes in the final layout as per the configuration I required.

Setting Up EasyEDA for a New Project

Step 1: Create a New Project

• Log in to EasyEDA.
• Click New Project → Name it "CN3058E LiFePO4 Charger" → Add a short description.

Step 2: Gather Component Libraries

• Search for CN3058E in the EasyEDA library.
• Add supporting components: resistors, capacitors, LEDs, USB Type-C connector.
• If a part is missing, import its footprint from LCSC or create a custom symbol.

EasyEDA is seamlessly integrated with JLCPCB, so once your schematic and PCB are complete, you can order your boards directly with just one click. This saves time, reduces errors, and ensures your design flows smoothly from idea to a real product.

General Procedure to Make a Circuit:

1. Wire Connections
Use the “Wire” tool to connect pins according to the schematic.

2. Name Nets
Assign clear net labels like VIN, VBAT, and GND for easy tracking.

3. Add Power Flags
Place VCC and GND symbols to mark power rails.

4. Annotate Components
Click Annotate to assign R1, C1, etc.

5. Electrical Rule Check (ERC)
Run ERC to spot unconnected pins or missing connections.

Building the Circuit Diagram

Time to connect everything together, once everything is gathered at one place, I am using 4 sections here listed as:

1) Input Section:

This is also known as the power input section, for I am using a 5V supply. And to do this, I am using a USB Type-C port configured for 5V input. Two 5.1 kΩ resistors (R6, R7) are connected to CC1 and CC2 pins for proper Type-C identification. Some pins are added if an external supply is required.

2) Charging Controller (CN3058E):

It contains the charging section of the schematic. I redraw the diagram, you can use certain labels and nets to connect different sections with each other neatly. For example, VIN is connected to pin 4 of CN3058E. ISET resistor (R2) sets the charging current, currently valued to 1.5K to produce 600mA. BAT pin outputs a regulated charge voltage to the battery. The TEMP we omitted this time because it is a single-cell charger, and operating conditions are not the worst here. Additionally, we have some decoupling capacitors (C1, C4, C5) near VIN to suppress noise. And C5, C6, and C7 near the battery point. 10 µF output capacitor for battery stability. 100 nF and 1 µF capacitors for filtering and transient suppression.

3) Indicators:

They are the simple LEDs used to indicate the battery state of charge. (LED1 for charging, LED2 for full charge).

4) Output:

The VBAT is the output of the IC, which is connected to the headers, and is used to connect the external battery later on. And the full schematic is given here, which completes the project schematic section and we are ready to move to PCB design.

PCB Layout Considerations:

We are not focusing on PCB design in this blog, but I shared some tips to make an efficient PCB, and the PCB view is shared also:

• Place the CN3058E close to the input and output capacitors to minimize trace length.
• Keep differential signals short for USB Type-C data lines.
• Use wide traces for battery and VIN lines to handle charging current.
• Place indicator LEDs at the PCB edge for visibility.

Conclusion:

So we have seen a design procedure of CN3058E LiFePO₄ Battery Charger with Protection from scratch in EasyEDA. It was a straightforward process once the steps were clear. From setting up the schematic to ordering the PCB. The key is following the datasheet, using correct footprints, and validating with rule checks.