diarmuid
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So I intuitively / physically understand a pole. Its a cap (parasitic or not), the charging /discharging of it drains the circuit gain and incurs phase shifts in the
circuit frequency response.
What is a zero then? I know its the oppositve of a pole (adds 20dB/dec, etc.) but physically - what is a zero?
Ive seen in a PLL, a zero is added to the LF by including a resistor. I know in op-amps, the RHP zero is moved to the LHP with a nulling resistor.
Therefore - physcially is a resistor a zero? If so, where does the frequency dependance of it come into play? i.e. a LHP zero with same frequency as a pole
cancels out the pole, etc.
Any advice much appreciated!
Thanks,
Diarmuid
circuit frequency response.
What is a zero then? I know its the oppositve of a pole (adds 20dB/dec, etc.) but physically - what is a zero?
Ive seen in a PLL, a zero is added to the LF by including a resistor. I know in op-amps, the RHP zero is moved to the LHP with a nulling resistor.
Therefore - physcially is a resistor a zero? If so, where does the frequency dependance of it come into play? i.e. a LHP zero with same frequency as a pole
cancels out the pole, etc.
Any advice much appreciated!
Thanks,
Diarmuid
