DIY Isolated UART to RS-232 Communication Module

Hello my name is Arda I'm a student also a electronics hobbyist.

The project currently I'm working on a modular test equipment (you can check updates about it from my twitter link down below) that has RS-232 pc connection for custom software controls. But because there is going to be something around 100V max. on the test equipment I don't want to fry my pc if any faults happen in the euipment.

So I designed this Isolated UART to RS-232 Communication Module. At the end the module we have is a 53.3mm x 40.6mm breadboard friendly isolated UART to RS-232 converter module that can be used to control things like DIN rail mounted industrial equipment some kind of truck scales. It isolates UART with 3 DIP-8 package 6N165 high speed opto-isolators. Then it converts already isolated UART to RS-232. Based on my calculations I can confirm that this module can work on least 9600 baud rate.

Assembly Tip

Solder SMD components before the THT components!

Schematic

Bill Of Materials

C1,C2,C3,C4 1uF 0805 capacitor

C5 10uF 0805 capacitor

R1,R2 10K 0805 resistor

R3,R4 1K 0805 resistor

U1 B0505S-1W isolated DC-DC converter

U2,U3 6N135 Opto-isolator

U4 SOIC-16 MAX3232 RS-232 Converter Chip

U5(3.3V) SOT-223 3.3V AMS1117 Voltage Regulator

Thanks to PCBWAY and their employees for great customer service and support for students like me to get sponsored pcb's.

You can contact and follow me from;

E-mail: arbildikda@gmail.com

Youtube: https://www.youtube.com/channel/UCI88RenozSfDrH9fCR6Azvg

Twitter: @arda_bildik link to profile: https://twitter.com/arda_bildik