INTRODUCTION TO BME
Lab II
INVERTING & NON-INVERTING OPAMP’S
FALL 2020
NAME & SURNAME: Nahla Almeamar
STUDENT ID: 62200046
DATE: 7/12/2020
Goals:
Learning about inverting and non-inverting op amps and how to set up and stimulate its circuit
on Ltspice.
Background:
Operation amplifiers are linear electronic devices that have the required characteristic for nearly
ideal DC amplification. Op-amps are built using many transistors and in general have a very
complex internal structure. The output voltage is the result of the difference between the input
voltages, amplified by a gain of A (open-loop gain)
Vout = A (V+ −V−)
Procedure and results:
Circuit 1:
TABLE 3.1: CIRCUIT 1
Resistor
Voltage
R1
R2
5.255 V
R3
R4
R5
2.367 V
4.734 V
2.367 V
0.011 V
TABLE 3.2: CRICUIT 1:
Resistor
Current
R1
2.3885 ma
R2
2.1518 ma
R4
588..2ma
INVERTING OP AMP:
Circuit 2:
TABLE 3.3: -Inverting op amp:
Resistor
R1
Rf
VOUTPUT
Voltage
9.9999
45.453
-45.45525252
Non-Inverting Op Amp:
Circuit 3:
TABLE 3.4: Non-Inverting op amp:
Resistor
R1
Rf
VOUTPUT
Voltage
9.999v
45.45402v
55.45v
Questions:
1-Compare between theoretical VOutput and experimental VOutput. Do
they match? Do they differ? Why.
Ans: comparing between the two there is no difference so they are considered
to be equal and the circuit is successful.
2-Compare between the input signal and output signal for both
circuits? Explain what happened to the input signal and why it
happened?
Ans: having the output in negative in both circuits implies that the amplifier
have negative feedback since the input is connected to the negative side.
3-What are the applications of op-amps in biomedical engineering?
Ans: Op amps are used in a wide range of electronic applications. Some of the
most common applications are a voltage tracker, a selective inversion circuit
and a current-to-voltage converter.
4-Explain how does the load resistance effect op amps?
Ans: Load resistance does not affect the transfer mechanism or the current
flowing through the node at the inverting op amp input.
References:
Internet websites such as:
https://www.allaboutcircuits.com/video-lectures/op-amp-applications/
https://en.wikipedia.org/wiki/Operational_amplifier_applications