As discussed in my previous posts I put together a simple AND gate circuit to combine the outputs of 4 IR receivers, to give my robot a full 360° coverage. Rather than etch a small PCB just for this circuit, I just bought some 7cm x 5cm prototype boards (dot matrix type) off eBay. Here are some pictures of the completed unit, including schematic and PCB design.
Here’s the design for the enclosure: http://www.thingiverse.com/thing:235106
Here you see the circuit, including a printout of the PCB that I drew up in ExpressPCB. I put the printout underneath the components to save me having to constantly refer back to the schematic.
The blank PCB that I used
Pictures of the module working on my LCD test board.
Below are the PCB layout that I printed (as seen in photos above) to help with layout and connections. The red and green colouring of the traces isn’t significant, it was just to help me distinguish between the different lines (+5v, GND, IR Module Outputs, AND gate output)
Bill of materials:
4 x IR receivers – TSOP4838
1 x dual 4 input AND gate – cd74hc21e