San José State UniversityCollege of Engineering/Electrical
EngineeringEE174: Analog Peripheral for Embedded Systems
Spring 2018
Lab #1: Op-Amp
Purpose:
To understand and become familiar with the basic principle of
the operational amplifier (Op-Amp) and be able to build various
types of op-amp application circuits.
References:
· Class Notes
· Op-Amp 741 specifications
Equipment:
· Breadboard, Op-Amp LM741 (3x), resistors: 2 kΩ(1x), 5 kΩ(3x),
10 kΩ(4x), 100 kΩ (1x) and capacitor: 0.03uF, 1uF.
· Power supplies and functional generator
Pre Lab Exercises:
· Read the data sheet for the LM741 Op-Amp and fill in the
following parameters.
Supply Voltage:
Bandwidth:
Input Offset Current:
Input Offset Voltage:
Slew Rate:
Input Voltage:
Supply Current:
Power Consumption:
· Calculate overall gain A = VO/V1 of the circuit below. What is
the input voltage V1 when the output voltage is VO = – 9.98V?
Lab Exercises:
· Build and test the basic forms of amplifiers as shown
below.
· Select R1 = 5kΩ, R2=5 kΩ, R3=5 kΩ and R4=10 kΩ to obtain a
closed loop gain of 2 for the non-inverting circuit U2 and the
inverting circuit U3. Measured the R1, R2, R3 and R4 to obtain
actual values and calculate actual gain for U2 and U3 circuits.
· Apply +15V and –15V to V+ (pin 6) and V– (pin 4)
respectively.
· Apply 1 kHz, 5V square wave (or sinewave) to obtain output
voltage V1, V2 and V3. Compare the theoretical voltage gain from
the above equation with the experimental value obtained by dividing
output voltage by input voltages observed. Record the error in
%.
· Measure and record the inputs v+ and v_ of each op-amps (U1,
U2, U3).
· Slew rate: Use result of unity gain circuit shown above when
apply 1 kHz and 5V square wave, measure the slew rate and compare
with the LM741 specification.
· Frequency Response:
· Select R3=2 kΩ and R4=100 kΩ to obtain a closed loop gain of
50 for the inverting op-amp circuit U3.
· Apply 10 Hz, 200 mV p-p and obtain the output voltage &
measured gain.
· Measure the gain for different frequencies between 10 Hz and
10 MHz.
Frequency
Input Voltage
Output Voltage
Measured Gain
10 Hz
20 Hz
50 Hz
100 Hz
1 kHz
10 kHz
100 kHz
500 kHz
1 MHz
10 MHz
· Plot the measured gain versus frequency and compare with the
specification of the LM741.
· DC Transfer Characteristics - Study the saturation limits for
an OP-Amp by applying an input of 1V p-p sinewave and record the
input and output. Observe the output and explain the results.
Record voltage values at non-inverting input v+ and inverting input
v-.
· Integrator: Build the integrator amplifier with R1 = R2 = R3 =
10 kΩ, C = 0.03μF (gain of 1) below.
· Apply an input of 1V DC. Observe and record the output.
Explain the result.
· Apply an input of 2 volt p-p at 1 kHz square wave. Observe and
record the input and output of the integrator. Use AC gain formula
to verify the gain.
· Change C = 1μF, record the output. Observe and record the
output. Explain the result (Hint: use AC gain formula).
Summary Report and Demonstration:
Write a detail summary, turn in the complete report (hard copy
and email soft copy) and demonstrate your results.
