To design and study the open loop gain from Non-Inverting Amplifier circuit. 

   Function generator, CRO, Regulated Power supply, resistor, capacitor, 741 IC, connecting wires. 

 

Non-inverting amplifier circuit design has been implemented on the virtual breadboard using following specifications:

·         Power Supply: +10v and -10v

·         Function generator: Selected wave with following specifications:

Frequency = 50Hz 
Amplitude: 750mV, 850mV, 900mV, 950mV, 1V, 2V. 
Duty cycle = 50% 

·         Resistor R₂:10.38

·         Resistor R₁: 1.369K

 

The operational amplifier can also be used to construct a non-inverting amplifier with the circuit indicated below. The input signal is applied to the positive or non-inverting input terminal of the operational amplifier, and a portion of the output signal is fed back to the negative input terminal. Analysis of the circuit is performed by relating the voltage at V₂ to both the input voltage V_in and the output voltage V_o. 
The output is applied back to the inverting (-) input through the feedback circuit (closed loop) formed by the input resistor R₁ and the feedback resistor R₂. This creates ve feedback as follows. Resistors R₁ and R₂ form a voltage-divider circuit, which reduces V_o and connects the reduced voltage V₂ to the inverting input. 

Figure 1: Non-Inverting Amplifier configuration of an op-amp

 

 

1.     Connect the circuit as shown in the circuit diagram.

2.     Measure the input and output voltage from the input and output waveform in the CRO.

3.     Switch on the power supply.

4.     Note down the outputs from the CRO

5.     Draw the necessary waveforms on the graph sheet.

 

 

1.     Observe the output waveform from CRO. A non-inverted and amplified waveform will be observed.

2.     Measure the input and output voltage from the input and output waveform in the CRO.

3.     Calculate 

 

4.     Compare the theoretical voltage gain from the above equation with the experimental value obtained by dividing output voltage by input voltages observed.

5.     Observe outputs of the inverting amplifier circuit using different input waveforms.

 

For example, a case has been taken and the required parameters values is being noted down below:

1.     Input Voltage: 1.94VV

2.     Frequency: 50Hz

3.     Output Voltage: 17.3V

 

 

1. Calculate experimentally observed voltage gain A_v using observed V_o & V_in from CRO.

 

 

2. Theoretically voltage gain is given by: 

 

 

Hence the opamp can configure as non-inverting amplifier circuit as observed from the output waveforms. 

 

1.     Connections should be verified before clicking run button.

2.     The resistance to be choosen should be in Kohm range.

3.     Best performance is being obtained within 50Hz to 1Mhz.