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What should be the output of the opamp?
The output should directly drive the negative input of the opamp. The input signal should be applied to the positive input, not the negative. Your circuit basically adds a capacitive load to the output of the opamp, then injects a signal on top of that. What you are seeing is not meaningful.
Which is the cut off frequency for an op-amp?
As shown in Figure 3, in the case of an op-amp with a low slew rate, a rectangular input signal appears as a trapezoidal signal at the output, and a sinusoidal input appears as a triangular signal at the output. Cut-off frequency (fT): Frequency at which the open-loop gain becomes unity gain (0 dB)
How does a capacitive load affect an op amp?
Op amps have an inherent output resistance, R o, which, in conjunction with a capacitive load, forms an additional pole in the amplifier’s transfer function. As the Bode plot shows, at each pole the amplitude slope becomes more negative by 20 dB/ decade. Notice how each pole adds as much as -90° of phase shift.
What is the slew rate of an op-amp?
Even when the ideal rectangular waveform (a fast-rising signal) is applied to the input of an op-amp, its output does not provide the ideal rectangular waveform as shown in Figure 3. A change in output voltage per 1 μs is called a slew rate.
How to check the opamp of an amplifier?
Connect the input signal correctly, try again, and report back. If you really want to check the opamp in inverting configuration, then you have to wire that right too. In that case, put a resistor between the output and inverting input, and a equal resistor between the input signal and the inverting input.
What does red mean on an op amp?
RED indicates op-amp output is positive. GREEN indicates op-amp output is negative. If the op-amp output goes above ground then Q14 will be on and it will source(supply) current outto the LEDs. Since the RED is forward biased it will turn on.
Where does the 741 op-amp get its current?
From the internal schematic of the 741 op-amp it should be clear that the output can source current from the \\$ V_{S+} \\$rail via Q14 or sink current to the \\$ V_{S-} \\$rail via Q20. In practice this would work as follows: simulate this circuit– Schematic created using CircuitLab