Problems and Fixes of the first design.

After the PCB’s arrived, I tested them and found the following problems:

  • IR Receiver caused a short circuit
  • Transistor didn’t switched the LED’s
  • IR LED’s were too dim

And these are fixes:

  • IR Receiver had the wrong footprint (GND and VCC were switched)
  • Transistor only worked with 5V, replaced it with a MOSFET with 1.7V threshold
  • IR LED’s current is raised from 20mA to 80mA
  • Relocated the power input connector
  • added a solder pad for the spiral antennas
  • Enlarged the traces for the LED’s

Ordering the new revision soon, so hopefully the first fully working design will be published soon. I will make a proper release on Github with the all the working files, including gerber files.

First design of the OpenMQTTGatewayPCB

The goal of this project is to make a PCB for the OpenMQTTGateway firmware, which holds almost every module there is available for it. Currently these modules are on the design:

  • IR (Send and receive)
  • RF (Send and receive)
  • PIR
  • DHT
  • Bluetooth (Module is mounted on the backside of the PCB)

Right now the diameter of the PCB is 91mm, so the case will be 100mm or a bit bigger. But if it is possible I will try and shrink the size of the PCB as much as possible.

First PCB design
First iteration of the schematic