Happy Thanksgiving
Ok so I’m late a day. Hope you all had a nice time. I watched the NC State vs Rider basketball game in the morning. We were horrible the first half but ended up winning the game. Then got back to work on my 214 circuit project. My spirits started to sink — I started uncovering some systemic errors in my formulation and was getting frustrated with Excel. The program lacks a useful interpolation function, and I was getting confounded by problems that should not happen — certain functions requiring the input cells to be the same worksheet, for example. It’s silly — I’m working with 20 worksheets in my file. I ended up migrating my entire design flow over to MATLAB. I ended up skipping out on the Thanksgiving Day dinner being help by the Graduate Community Center and opted to have some leftover rice pilaf. I continued working straight through the evening and it started to pay off — I was getting results. All my transistors were in the right mode of operation. Jimmy and his partner called and I ended up talking him through part of the project over the phone for over an hour. I’m meeting 2 of the 4 requirements, but I’m having trouble increasing my amplifier’s gain. You see, increasing the gain of an amplifier reduces its static error. The reason is that my dynamic range is only 76 dB, when I need it to be 90 dB. So I have to both increase gain and reduce noise.
I celebrated by warming up some chili and canned corn. I tried some other strategies on improving my gain, but unfortunately nothing really worked. I think I’m going to have to reverse my design…basically swap my n-mos and p-mos transistors. So far I’ve put about 35+ hours into this project…better now than during the upcoming weeks.
Not planning on much at all for Black Friday. Don’t really need anything. Except maybe a webcam for home.
Win Said,
November 23, 2007 @ 7:14 am
Have you thought about using Agilent ADS? You can use sliders to change transistor values easily and see their effects, or you can say “make my range 90 dB, but keep my static error low” and have the software optimize it for you until you get something that you like.
Saket Said,
November 23, 2007 @ 12:24 pm
Woah, i haven’t used ADS before. The sliders would be useful too. Right now it’s a lot of hand optimization.
The one problem I foresee is if ADS doesn’t integrate with our circuit simulator, HSPICE. I’ll check if ADS is installed here though.
Thanks!