In the experiment 6 for BPF, the input to the CR circuit op-amp is square wave, what is the output of this op-amp looks like

In the experiment 6 for Band Pass Filter (BPF), if the input to the Capacitor-Resistor (CR) circuit operational amplifier (op-amp) is a square wave, the output of this op-amp would be a band-pass filtered version of the square wave.

Here are the steps to understand this:

1. A square wave is a non-sinusoidal periodic waveform (which can be represented as an infinite summation of sinusoidal waves via the Fourier series), and it includes a wide range of frequency components.

2. When this square wave is input to a Band Pass Filter (BPF), the BPF allows only a certain range of frequencies to pass through and attenuates the frequencies outside this range.

3. The CR circuit in the op-amp forms a BPF. The resistors and capacitors in the circuit determine the range of frequencies that the filter will allow to pass through.

4. Therefore, the output of the op-amp will be a band-pass filtered version of the square wave. This means that the output will still be a wave, but its shape will be distorted compared to the original square wave, depending on the frequency range of the BPF.

5. The output wave will have its high-frequency components (above the pass band) and its low-frequency components (below the pass band) attenuated, and only the frequency components within the pass band will be preserved.

6. This can result in a wave that may look more like a "rounded" square wave or even a sinusoidal wave, depending on the exact frequency range of the BPF.

Remember, the exact shape of the output wave will depend on the specific values of the resistors and capacitors in the CR circuit, which determine the pass band of the BPF.