MEP EP#242: The Heartbeat of Cats and LEDs

<h4><a href="https://macrofab.com/blog/mep-ep242-the-heartbeat-of-cats-and-leds">MEP EP#242: The Heartbeat of Cats and LEDs</a><br></h4><h4>Parker</h4> <ul> <li>Battery charger and maintainer died <ul> <li>Took all my batteries with it</li> <li>Company is replacing the unit</li> <li>Nothing looks particularly wrong with the PCB Assembly besides it being gross</li> <li>SF1565SG <ul> <li>Current Mode PWM Controller</li> </ul> </li> <li>FQPF12N60C <ul> <li>Fet used in the PWM Controller</li> </ul> </li> <li>HT46R004 HolTek MCU <ul> <li>Cost Effective? </li> </ul> </li> </ul> </li> <li>Cat Feeder Unreminder <ul> <li>Ordered a <a href="https://www.tindie.com/products/jaspersikken/solar-harvesting-into-supercapacitors/" target="_blank" rel="noopener">breakout board</a> for the AEM10941</li> <li>Super Caps SCCS30B106PRB <ul> <li>10F @ 2.7VDC </li> </ul> </li> <li>Solar Panel AM-1816CA <ul> <li>84µA at peak power</li> <li>This is specced at 200lx</li> </ul> </li> <li>Will this be enough? <ul> <li>LTC2956 draws 0.8μA</li> <li>LEDs at 40μA a piece</li> <li>Total draw when Cat Feed Indicator is on is 40.8μA</li> <li>5F x (4.5V-3.6V) / 0.0000608 = 74,013 seconds -&gt; 20 and a half hours!</li> </ul> </li> </ul> </li> </ul> <h4>Stephen</h4> <ul> <li>Magnetics <ul> <li>Transformers arrived!</li> <li>Be specific with what you ask for and ask questions. I almost got bit with dimensional issues</li> </ul> </li> <li>Diy Tag connect <ul> <li>Made a pogo pin test connector</li> <li>Mill-Max 0955-0-15-20-71-14-11-0 Pogo pins with solder cup on back </li> <li>Using FR4 as mechanical supports</li> <li>Designing a Pawl system to clasp the pcb</li> <li>Next Revision <ul> <li>Make the landing pads bigger</li> <li>Add something for strain relief</li> <li>Move the pins slightly down for more spring</li> <li>Add more anti rotation pins</li> </ul> </li> </ul> </li> </ul>