Before namely the LT317A using the DC sweep

Before
creating an electronic device or circuit, simulation always comes first to
identify the outcome of a created design through the use of mathematical
models.  And because of technological
advancements, different software have been made and used in simulation of
electronic devices and circuits. One of the most popular and widely used
software in designing and simulating electronic circuits is the LTSpice.
LTSpice is a free-for-all computer software which utilizes SPICE (Simulation
Program with Integrated Circuit Emphasis) in designing and simulating
electronic devices and circuits. It is a useful tool because it gives you
guidelines on how your circuit design will work. It can also serve as a tool
for visualizing your desired circuit design before actually creating it. And in
LTSpice, the learning and testing a circuit will be more convenient because of
its feature that allows you to examine the waveforms on different parts of the
circuit. In line with this, the students have familiarized themselves with the
basic SPICE directives used in this laboratory experiment.

In
the first activity, a basic voltage divider was simulated. The .param command used designates the
value of the resistor. The .step param command used creates a step function
which varies from 1k to 10k with a step of 2.25k. The .tran command calculates
the non-linear algebraic-differential equations of the voltage divider circuit
with a stop time of 10 seconds. Then, in the second activity, we simulated a
linear voltage regulator, namely the LT317A using the DC sweep function. The
.dc command calculates the DC analysis of the voltage regulator circuit and
increasing or decreasing the applied voltage. In the third activity, we
simulated a second-order band-pass filter. The .ac command used calculates the
small signal analysis of the filter linearized throughout its DC operating
point. And in the fourth activity, we simulated an ideal operational amplifier
using the transient analysis. The transient analysis calculates the non-linear
algebraic-differential equations of the operational amplifier with a stop time
of 100 milliseconds. The .param command gives the resistors a fixed value.
While in the fifth activity, we simulated a pulse signal using the pulse
function from the voltage source. The signal created is similar to the signal
used in the input/output ports of an Arduino microcontroller. The .tran command
calculates the non-linear algebraic-differential equations of the voltage
divider circuit with a stop time of 40 milliseconds. Lastly, in the sixth
activity, we simulated a full bridge rectifier using the step parameter. It has
an input voltage of 120 Vpk-pk and a frequency of 60 Hz to be converted to a
120V pulsating DC. The step parameter displays the essence of using different
capacitors as a filter, namely 10 uF, 90 uF, and 100 uF capacitors.