I finally broke down and bought the student version of MATLAB. Even though I feel that Mathematica is superior to MATLAB, especially when it comes to data visualization and symbolic math, the fact that my linear circuit analysis class requires that you use MATLAB was enough to push me to the dark side. I’ve made a special plot using MATLAB to break it in. This is a plot of the output voltage of a boost regulator that I made using some spare parts. It takes 5V and outputs up to 30V. The output voltage is measured using a voltage divider and an ADC on an ATMega168. This reading is printed to the UART (for logging, this is how I produced the plot) and it also adjusts the duty cycle of a PWM on the AVR to regulate the output to the desired voltage. From the plot you can see that using a bigger capacitor helps minimize the voltage ripple but it also seems to let the duty cycle vary a lot. Perhaps some simple averaging or rate limiting could help lower the ripple even more. I was shooting for 20V output, but it keeps wanting to output a bit higher. Maybe I need more precise measurements of the ratio in my voltage divider. Regardless, the precision and accuracy of the output voltage isn’t too important, it gets regulated down to an accurate voltage up to 16.5V using an op-amp. Why go to all this trouble? I’ll explain in a later posting…
Published
on Tuesday, March 11th, 2008 at 5:04 pm
Welcome to “the dark side”, heh heh!
Seriously, I think that many of these tools are useful, and you are correct that they have strengths and weaknesses.
Good luck with MATLAB! I hope you get as much out of it as I have.
-Will
1 | Will Dwinnell March 28th, 2008 at 7:29 amData Mining in MATLAB