Hardware
Figure 1: Final assembly
An SR-Latch is an integral part of computer memory. Two transistors and a few biasing resistors can store one bit of memory (a high or a low). I found that this was worth learning properly as it is the foundation of how computer registers and memory works. I found that this project would also allow me to invest more time into learning about the computer's hardware side to better understand how it functions and how to best utilize these functions in the future.
In order to plan and verify the design I was using for the SR-Latch. I first needed to create some simulation files to test what the outcome of the circuit would be. I found that the best way to do this would be through the use of LTSpice, which is a spice-based simulation software we use in university projects.
Figure 2: SRLatch simulation in LTSpice
This helped to verify that, in theory, my design was correct and that it would likely work as expected. The next step was to assemble the circuit onto a breadboard, allowing for easy modification where necessary.
Figure 3: SRLatch breadboarding
Throughout this project, I learned about how transistors are used as computer memory and what it means when people say computers contain trillions of transistors. I also learned how important it is to select the correct components for a given job. Although I was designing a small circuit that would only turn on two LEDs, it is always important to consider the lifetime and purpose of the circuit. I should have considered that this project is run off of a battery and that perhaps more care should be put into selecting the resistor values or the type of transistors used, as these could have limited power usage.
Moving past this project, I would like to take the things I have learned (through this project and my university electronics paper) to design an adder circuit. This will be useful for me as it contains many logic gates, which are essential to understand for computer operation. Furthermore, it will allow me to better grasp how computers can add large numbers and why it can often take multiple clock cycles to do so.
