The engineering interview – interesting and challenging questions, Part I
It is absolutely true that the most successful engineering companies hire the very best and very brightest talent. It’s even more so true in startup firms such as Touchstone. As a result, my colleagues and I have interviewed a great many candidates for openings in design, test, product, and applications engineering in our past and today.
When I stared at the keyboard (again!) to write this next blog, I was thinking about the tons of thought-provoking and interesting test questions I myself have had to endure and the ones I have meted out to nervous and not-so-nervous candidates.
So, while rummaging around the garage one evening - lo-and-behold in a dusty file cabinet behind the bikes, the little-used/long-forgotten pair of skis, and the shop vac - I managed to extricate from a 3” hanging folder hundreds of engineering test questions collected over 30 years – many contributed from engineering colleagues with whom I worked at Hughes, ADI, LTC, and elsewhere. As you can tell from the title, I’ll be returning to this topic from time-to-time.
One of the more interesting take-aways is that you never know how a candidate will react to the questions regardless of his or her experience – that’s why I rotate through a short-list of about 20 primo questions queued up in increasing difficulty to challenge the real brainiacs.
Here’s one of my favorites: Let’s say an analog multiplier is used inside the feedback loop of an op amp as shown in Figure 1. If the analog multiplier exhibits a transfer function as shown in the figure, how would you answer the following (3) questions?
Figure 1: An analog multiplier inside the feedback loop of an op amp. What's the circuit's function?
Question #1: What is the overall circuit’s function?
Question #2: What is an expression for the circuit’s VOUT if R1 = R2 = R?
Question #3: What limits should be placed upon VIN, if any?
Share some of your favorite candidate interview questions or an interesting technical question asked of you in an engineering interview – I think the results will be really interesting and I just might add novel ones to my catalog.