LM741 operational amplifier is old but very popular op-amp which are still found in the electronics market. Most op-amp works well with dual power supply but many times we do not have proper dual power supply. Op-amp can also be operated using single supply which requires biasing of the op-amp which was illustrated in tutorial biasing LM741 for Single Supply with Split Resistor Biasing and how to operate LM741 with single supply. Here we illustrate how LM741 op-amp can be operated using dual supply obtained from a single supply voltage. The designed amplifier is then assembled on a breadboard and tested in real time with Proteus Software.
See the following video for demonstration.
The following is the circuit diagram of ac-coupled non-inverting amplifier using LM741 op-amp.
In the above circuit diagram we have used single supply voltage of 9V and used voltage divider resistors R5 and R6 to obtain +4.5V and -4.5V which are used for the +ve and -ve terminal of the LM741 op-amp. The resistor R1 and R2 sets the gain of the non-inverting amplifier. For R1 we have used 10KOhm potentiometer in order to make the gain variable according to requirement. The capacitor C1 is used to couple the input signal into the amplifier circuit and the resistor R3 provides the dc path for the input signal. The following video demonstrates simulation of LM741 amplifier with dual supply obtained from single supply voltage using Multisim Software.
The following shows the LM741 non-inverting amplifier using dual supply from signal supply voltage of 9V assembled on breadboard.
The above circuit on the breadboard can be tested in real time with matlab/simulink based PC oscilloscope like in the tutorial LM358 Op-Amp Integrator Test with Matlab Simulink Oscilloscope or using soundcard oscilloscope using Labview like in the tutorial How to operate LM741 with single supply.
Here we will demonstrate how we can test the LM741 amplifier circuit on the breadboard using Proteus Software in real time. With proteus speaker and microphone circuit components we can send out signal from the speaker into the LM741 amplifier on the breadboard circuit and acquire the output from the amplifier using the microphone component in proteus. For this we need to have two male to male audio jack. The proteus has function generator which can be used to output various waveforms such as sine wave square wave, triangle wave etc. The oscilloscope in proteus software can be used to visualize the input and the output signal in real time.
The following shows the speaker and microphone are configured in the proteus software to real time waveform generation using speaker and signal acquisition with microphone.
The signal generator is used to output different waveform to the PC speaker.
And the oscilloscope can be used to visualize the signal waveform in real time.
The amplifier on the breadboard is connected to the PC speaker and the microphone/ line in port as shown in the picture below.
So in this tutorial we have shown how one can build non-inverting amplifier using LM741 or uA741 operational amplifier using dual supply but with voltage split of a single supply of 9V. We showed how one verify the amplifier on breadboard using Proteus software running on PC with audio jack.
Similar tutorials that are useful and uses other methods of testing circuits are as follows:
- LM358 Op-Amp Integrator Test with Matlab Simulink Oscilloscope
- How to use Matlab Simulink as Oscilloscope
- Real Time Simulation of BJT amplifier using Proteus & PC Soundcard
