Feedback Lab 1 (i.e. hints lab 2)
Some general FB for lab 1 that might help improve the quality of the report for lab 2...
- Answer all explicit questions and try to answer the implicit ones as well. Example: "Are there any deviations that indicate that there are some effects that the EKV model does not model?"
- Follow all instructions! Example: "Enter the parameters into the EKV matlab function (You’ll find it under ’resources’ on the course page) and plot the result together with your measurement to verify your match." So plot the graphs together, as instructed!
- Give all necessary information to enable replication of your results. Some of you did not mention the value of V_DS for the I_D vs V_GS plots. And vice versa only specified "strong inversion" for I_D vs V_DS plots instead of also explicitly giving the value used for V_GS.
- Make figures readable! Use big enough labels (In Matlab, for example: set(gca,'fontsize', 14). Label the axes (use 'xlabel' and 'ylabel' in matlab) with a variable neame and unit, e.g. 't[s]'. When plotting data with a limited number of samples, mark the points, e.g. in matlab adding a style string in plot: plot(x,y,'-*'). You can also mark individual points that way: plot(x(20),y(20),'o'), and insert text into plots with the command 'text': text(x(20),y(20)+0.001,'this is the -3dB point').
- Show schematics, i.e. of the circuit you assembled in the lab and in Cadence. Makes it easier to debug, aslo for yourselves.
- Use figure numbers and captions! Easier to reference specific figures that way, both in your own text and when receiving feedback from the examiners.
- Use legends when plotting multiple graphs in the same figure. Check out function 'legend' in matlab.
- Make use of tables when doing the same experiment multiple times with different parameter settings to report these parameters and results.
- In tasks 2 & 3 many people had difficulties extractin parameter I_S from the measurements. Ask yourself: how does a different I_S affect the curve and you might find a way to find a way to determine I_S for a specific measured curve, e.g. by looking at a specific point or slope. Solution will be discussed next lecture.
- After parameter extraction from the meaurement, some groups did not make much of an effort to improve the matching by fine tuning the parameters. This would have been good to enahnce understanding on what effect those parameters actually have on the curves. Also: not many did plot both the V_GS and V_DS plots to compare the measurement or simulation with the EKV model (follow instructions!).