HW Interview
SD-04 · Chapter 12 · System Design (Open-Ended)

Smart pet-collar tag

Design a smart pet-collar tag that tracks activity, shows the pet's status with a small LED, and runs six months on a coin cell.

Level●●● onsite design / senior
TrackSenior system
Really testingUltra-low-power wearable design.
Full worked answer: in the book, page 290 — what to say first, how to explain it, the numbers worth quoting and the follow-ups. About the book →

Going deeper

Extra explanation that is not in the book: worked numbers, where people go wrong, and how to say it in the room.

Going deeper for this question is coming.

Errata

No corrections known for this question. All errata

Ask about this question

Stuck on a step, or think something is wrong? Send it with SD-04 in the subject. Good questions get answered on this page, and corrections go into the next printing.

Ask about SD-04

Related

← SD-03 Powering a remote FPGA card over a harnessSD-05 Matching microphones at volume →