I was contacted three weeks after applying to schedule an initial interview, which took place several days later. The interview was an hour-long technical interview with two engineers. As others here have mentioned, the questions were heavily focused on circuit design. You really need to study for this if you come from a pure ComSci background. They did ask a few programming questions as well, but they were very simple and high-level. The interviewers were polite throughout the process and discussed the nature of the position with me and answered my questions. I was contacted about a week and a half later to schedule the next series of interviews, but I had already accepted another position by then.

What are a diode and a transistor, and what are they used for?

Draw a diagram of a NAND gate using transistors, then write out the truth table.

Explain how to swap the numeric values of two variables without making use of a third.

Write a function (in pseudocode) to determine the number of '1's there would be in the binary representation of a number.

What are setup time and hold time?