OP-Amp Inverting Amplifier and Virtual ground Explained with Examples

In this video, What is inverting configuration of op-amp, How inverting op-amp works, Why negative feed back is required in op-amp, What is concept of virtual ground, What is the voltage gain of inverting op-amp, What is input and output impedances of inverting op-amp, all these concepts explained with examples and derivations. OP-Amp Inverting Amplifier: In Inverting configuration, An I/P signal is applied through I/P resistor Rin to the Inverting terminal of OP-Amp and the O/P is feedback to the same Inverting terminal through feedback resistor Rf. The Noninverting terminal is connected to the ground, Note that the resistor Rf provides negative feedback. Since the I/P signal is applied to the Inverting terminal, the O/P will be inverted that is 180 degrees out of phase as compared to the I/P. Hence the name Inverting amplifier, Virtual Ground: The virtual ground concept is applicable for only negative feedback, An OP-Amp has an infinite I/P impedance, Which means that there is zero current at Inverting input, If there is zero current through the input impedance, then there must be no voltage drop between the inverting and noninverting inputs, Which means that voltage at inverting input is zero because the noninverting input is connected to ground. The zero volts at inverting input terminal is referred to as Virtual ground because it is at zero volts but is not physically connected to the ground. Inverting OP-Amp voltage gain: The close loop voltage gain of inverting amplifier is ACL = -Rf/Rin, The negative sign indicates that the output signal is inverted as compared to the input signal, I/P & O/P impedances of Inverting OP-Amp: The input voltage passes through the input resistor Rin that is going to virtual ground, Thus the input impedance for the inverting amplifier is Zin=Rin, The output impedance of the inverting amplifier is the parallel combination of feedback resistor Rf and the output impedance of OP-Amp itself, The presence of the negative feedback reduces the output impedance of the amplifier to the value that is less than the output impedance of OP-Amp. The timestamps for various topics covered in this video are as follows, 2:54 - OP-Amp as an inverting amplifier, 3:28 - Concept of virtual ground, 4:24 - Voltage gain of inverting amplifier, 7:06 - Input and Output impedance of inverting amplifier, 8:08 - Examples with Solutions. Links for related videos on OP-Amp, Op-Amp Basics: https://www.youtube.com/watch?v=aV_ll​​​... Op-Amp Parameters: https://www.youtube.com/watch?v=jhtPW​​​... Op-Amp Input and Output offset voltage https://youtu.be/GvAlSuXSt5o​ Op-Amp Input Bias current and Input Offset current https://youtu.be/jZYQLlwbvNE Music Credit: http://www.bensound.com/​​ Please SUBSCRIBE my YouTube channel. "Keep Learning and Keep Growing".