Answer Happy

2. Oscillator: An oscillator circuit can be easily built with an op-amp, and a few components. In this circuit, op-amp functions as a comparator. The op-amp is using positive feedback, and the inverting input of the op-amp with the R3 (feedback resistor) and C1 is used as a capacitor charger/discharger. As shown in the diagram below, the non-inverting input (+) is a voltage divider of the op-amp output voltage. The inverting input (-) is connected to a capacitor that continuously charge and discharge depending on positive or negative voltages on the output of the op-amp. The result is the generation of a square wave on the output of the op-amp (pin 6). a) Build the circuit below. Measure the output voltage using the oscilloscope. Connect channel one of the oscilloscope to the output of the op-amp (pin 6). Adjust the timing scale and volt per division scale to see the waveform on the oscilloscope. Draw the waveform in the oscilloscope figure below, and label it as Vo. b) Carefully connect channel two to the junction of the capacitor and the inverting input to the op- amp. Draw the waveform on the oscilloscope figure below, and label it as Vc. R3 w 40ko VEE -15V U2 5 C1 0.01F 741 SR1 > 6.490 1 vec 15V R2 6.490 Figure 1 Oscilloscope