Issue link: https://iconnect007.uberflip.com/i/1523825
JULY 2024 I DESIGN007 MAGAZINE 79 cision analog data from two ADCs (analog to digital converters), which take in a signal from external sensors. All these different signals— both analog and digital—are involved. It's dif- ficult to keep noise levels down and maintain accurate readings on the analog signal, in addi- tion to using the buzzer, which can also create electrical noise. On the power side, the digital microcon- troller and all the digital components use 3.3 volts, but all the analog components use 5 volts to achieve a higher dynamic range from the readings. Keeping the analog and digi- tal ground planes separate is important for eliminating digital noise in your analog signal, as that can mess with your readings. With all those considerations, it took a long time to develop the design, but it's paying off because it's working as expected. Alex, looking back on college, do you ever wish these things had been covered in school? I would say the class should cover not only learning the PCB design soware, but actu- ally getting the board back from the fabrica- tor, soldering your own components on it, and then debugging the board. at's as much as you could ask for in a basic PCB design course, which George Fox excelled at. Your board may not work like you expect it to, because it's the first design you ever do, so the debugging pro- cess is really important. Dr. Spivey emphasized that if something were to go wrong, we would need features in the design to make it physically fixable aer you get the board. He definitely wanted us to make sure the board was debuggable. at might include adding vias or debug points on the board, or bringing all your IO pins out to headers accessible to a logic ana- lyzer, allowing for soldering a wire from one place to another, or adding a resistor some- where. Otherwise, if you get that board back and it doesn't work, there are few options but to throw it in the trash. In my career now, that process taught me that cost is so important for boards expected to be mass-produced. Every component mat- ters, whether it's just one extra capacitor or one extra diode. It's not only the component that adds cost, but the addition to the layout and physical placement. For example, let's say speaker wires need to be connected to your board. In most applications, the wires can be soldered directly to the board. You don't need the modular functionality you get from having connectors, which comes with additional cost. Of course, as a debug feature, it would be great to have, but not needed in a mass-produced product. ose connectors could be 50 cents each, and that adds up quickly. How do you feel about your career choice at this point? I absolutely feel like this was a calling. From a young age, I was interested in electronics, computers, and soware. As far as being in this industry, these are things that I'd be doing no matter what. If I were to retire tomorrow, I'd still be doing this, even if I wasn't getting paid. Alex, what advice do you have for current college students? My advice is to at least dabble in those fields you might be interested in. You won't know if you don't try it. I've been doing this since mid- dle school, so I was fortunate, but if you don't know, then learn more about it. Do something hands-on in that field, whether it's job shad- owing, taking an introductory class, or talking with people in the field. It all helps, and it's all important. It's okay if you don't get it right the first time. It's okay if you need additional education and training. It's a lot better than working in an industry you don't like for the rest of your life. Alex, thank you. I wish you continued good luck in your next five years and beyond. ank you, Nolan. It's been a great opportu- nity to reflect. DESIGN007