Exploring Integrated Circuits

Exploring Integrated Circuits Introduction Methods Integrated circuits (IC’s) are small electronic components made of transistors, diodes, and resistors all connected onto a small silicon chip. The complexity of IC’s allows them do a variety of functions, such as producing, amplifying, and responding to voltages. We focused on two types if analog IC’s: the 741 operational amplifier (op-amp) and the 555 timer. By connecting the Analog Discovery Studio to a laptop, signals sent through the wavegenerator, amplified or modified by the circuit on the breadboard, and finally received by the oscilloscope, were displayed and measured in the WaveForms application. Circuits built using the 741 op-amp include non-inverting and inverting amplifiers, low pass and high pass filters, a summing amplifier, and a basic comparator. Through the amplifiers, we observed the frequency Fig. 2: A non-inverting amplifier with unity gain connected to and amplitude relationship and how the the WaveForms application. The screen shows an input sine amplifier gain affected this relationship. wave signal of frequency 1 kHz and amplitude 1V with an output signal of 1V. Fig. 1: On the left, a 741 op-amp and its circuit diagram. To the right, a 555 timer and its circuit diagram. Circuits built using the 555 timer include the astable circuit, which demonstrated how the comparators inside the timer function, and a frequency divider, which made the output frequency half the input. We then paired with the wave generator with an Arduino to control an LED. Fig. 3: Coding the Arduino transforms analog signals from the wave generator into digital signals for the LED Results Conclusion In this section, I will discuss how we built inverting amplifiers with different gain values to observe the frequency and amplitude relationship. For unity gain amplifiers, meaning when the amplifier gives an output signal with the same amplitude as the input signal, we found that the 741 op-amp can handle frequencies up to 100 kHz before the signal collapsed. Building different types of circuits and amplifiers gave me insight into what electrical engineers do. I have learned about how IC’s operate and their capabilities in working with electrical signals while also learning more simple things, like how to interpret circuit diagrams. I look forward to creating my own electronic projects in the future. Fig. 4: For different types of waves, the cut-off frequency in a unity gain inverting amplifier is around 100 kHz. By adding resistors to the circuit, one can increase the amplifier’s gain. When repeating data collection with amplifiers with a gain of -5 and a gain of -10, we found that the upper frequency limit decreased as the gain increased. Fig. 5: For inverting amplifiers of gain -5 and -10, the cutoff frequency was 10kHz and 1kHz respectively.