I applied online via LinkedIn in October 2019, and had their HR rep call me about a week later and give me a phone screen regarding my resume and work experience. They then scheduled an on-site interview in Irvine for late October, almost 2 weeks after the phone screen.
The first step in the on-site interview process was to give a 15-20 minute long presentation about a past engineering project I had done to a panel of their engineers plus the CEO (since they're a very small company). After fielding questions regarding my presentation, there were 2 more 1:1 sessions where one of their engineers asked more in-depth questions regarding my experience and other past projects. They did not ask me any algorithm questions from what I remember, but did ask some general embedded knowledge-based questions, such as how to implement I2C or SPI. They also gave me a short tour through the office space and lab: there were no cubicles at all (a major plus for me!), and instead had a more open-office setup, along with lab benches setup through the other half of the workspace.
Overall, I thought I had done pretty well during the on-site interview. However, I heard back from my HR rep about 2 weeks after my on-site interview indicating that they were moving forward with other applicants instead.