Tester circuit

The circuit consists of an operational amplifier that polarises a MOSFET. The current is controlled by a voltage which is the positive input of the amplifier. This voltage is the voltage that is forced through the resistors, connected to the source terminal in the MOSFET, and therefore a current flows through the resistor, which polarises the transistor. Instead of 1 transistor, 2 transistors are placed in parallel to increase the current output.

The current has a maximum value of 1A (max discharge rate). The limiting elements are the MOSFET due to heat dissipation issues.

To measure the voltage in the battery a voltage divider is introduced so it can measure up to 10V. Also, a temperature sensor is set to be near the batteries or cells to monitor temperature during the test. If the temperature reaches a certain value the current flow is stopped.

User interface

The interface is a set of buttons that control the LCD through an interactive menu. This menu has been designed to be as intuitive as possible. The capabilities are optimized in the software in the Arduino so you can control the current flow. The Arduino is capable of saving data over the last 9 tests done.

The software can be updated to increase its functionalities if required. For example, integrating the PCB with Matlab for graph obtention or increasing the memory slots for the tests.

Ordering the PCBs at jlcpcb

This project is sponsored by jlcpcb. jlcpcb is a full feature Printed Circuit Board manufacturing service.

Turn your DIY breadboard circuits into professional PCBs – get 10 boards for approximately $5 + shipping (which will vary depending on your country).

Once you have your Gerber files, you can order the PCB. Follow the next steps.

1. Download the Gerber files – click here to download the .zip file

2. Go to jlcpcb website and Click on Quote Now button. 

3. Upload the gerber file you downloaded in the last step. Upload the.zip file or you can also drag and drop the gerber files.

After uploading the zip file, you’ll see a success message at the bottom if the file is successfully uploaded. You can review the PCB in the Gerber viewer to make sure everything is good.

jlcpcb can grab all the PCB details and automatically fills them for you. But you can also

To place the order, click on “SAVE TO CART” button

Before finalizing your order you can use the promotional code JLC-REBE to get a discount and then click pay.