Today we covered Ohms Laws, Kirchoff's Current Law, and Kirchoff's Voltage Law. We also learned about Conductance (G) as well as MOSFET type transistors.
For our first exercise, we have a circuit created by Professor Mason. Here we are asked a couple questions to make predictions on what will occur. Our predictions ended up being incorrect.
Here we have the equation V=IR and we are asked if graph A or B is possible. We said that neither could happen since you can't have voltage without a current and via versa. This is partially true since there is an exception for a diode where there can exist a voltage without a current.
Another application of Ohms Law where we use passive sign convention to solve a basic circuit element. Now we look at which elements in the circuit absorb power as a positive number in doing calculations.
Another technique that is useful in helping to use the laws that we just learned is to break down the circuit into branches and nodes.
Dependent Sources and MOSFETs
A MOSFET transistor is like a gateway. This gateway will open (or close) only after a certain threshold of voltage is applied to it. In this case, the "gate" will only open once 1.5 volts is reached. MOSFETS are calso classified as a Voltage Controlled Current Source (VCCS).
This graph is credited to my group member Adrian. It is a plot of data of the MOSFET around the voltage in which the "gate" is opened. As expected, the opening and closing of the transistor is an exponential function. At the top of the graph we have the situation where the transistor pretty much operates like an open wire on the circuit. This means that the transistor has the same conductance then an open wire. This graph would have a better plot if we used smaller step up increments to get more data points in the middle portion of the graph.
Resistors and Ohms Law
In this experiment we are introduced to a program called Waveforms along with the Analog Discovery tool. The Analog Discovery tool allows us to provide plus or minus 5 volts to a circuit and will give us readings just like a multimeter. These readings show that the readings are very close to the calculated values.
From the above data collected we were able to create a graph to find the equation for the least-square best fit line. From the graph we get Current=0.0091Voltage - (Some initial value). This linear relationship shows that for every current in the circuit we will have 0.0091 volts.
