You build a CMOS inverter for your boss and she asks you what the input capacitance is. You answer: “I'm not sure, but I will find out right away!” What you should have been able to say to her is: “Well, boss, the first thing I did was to familiarize myself with the 12nm CMOS process and I found that the input capacitance is 0.8 fF/μm, so of course my 7μm PMOS, 3μm NMOS inverter has about 8 fF of input capacitance. ” But you didn't say that, because you didn't know. You are a spice monkey.
]]>One of the most important fundamental features of any computing system is the ability to store data to memory, recall the data, and overwrite the data. By memory, we mean the ability to store things, recall them and change them if necessary, referring by analogy to our concept of human memory.
]]>I found two good reasons to teach tutorials. First, I enjoyed it. I liked imparting my knowledge to students and helping them learn. I am amazed at how quickly students absorb knowledge and I am often impressed with the depth and intelligence of their questions. The second reason to teach tutorials is to learn the material. Of course, you probably know the material, but if you really want to know it, then you should teach it. In fact, teaching is a good test of understanding. If you can teach it, you understand it. Sadly, it's not necessarily true that if you understand a topic, you can teach it. I'm sure many of you have seen this proved by seemingly intelligent professors who couldn't teach a kangaroo how to jump. It's takes sincere effort to construct a concept in a way that's understandable to others.
If you're still not convinced, don't listen to me, listen to Nobel-prize winning physicist Richard Feynman:
]]>Content-addressable memories (CAMs) are hardware search engines that are much faster than algorithmic approaches for search-intensive applications. CAMs are composed of conventional semiconductor memory (usually SRAM) with added comparison circuitry that enable a search operation to complete in a single clock cycle. The two most common search-intensive tasks that use CAMs are packet forwarding and packet classification in Internet routers. I introduce CAM architecture and circuits by first describing the application of address lookup in Internet routers. Then we describe how to implement this lookup function with CAM.
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