Standard phone screen first, followed up with about half a day of interviews. This was for a firmware engineering position for a SOC type of architecture. The questions on site is mostly technical and focused a lot on how you would solve a particular problem. I find it really refreshing because a lot of interviews tends to focus on "do you know what this volatile keyword do?" which is useful but doesn't really gauge a candidate's capability. They focused far more on problem solving skills, asking questions and debug scenarios on things you have not done before, on how you solved prior difficult situations at your previous experience, etc. Be prepared to think outside of the box. I also find that the people who did the interview are very sharp and smart engineers and that is a major plus in the decision process. It was a really good and engaging process but you should definitely be prepared to be challenged.