Jim wrote:
Is a higher degree loop possible while maintaining stability?
Sure. PLL control loops (and other feedback loops) are often designed out to fourth and fifth order. Very simply put, the requirement is that the loop must have a reasonable phase margin at the frequency where the gain reaches unity. For multiple open-loop poles (where this condition would not be met), the usual solution is to "give back" all but one pole by cancelling them with high-frequency zeroes. All of this can give useful improvements in loop gain at low- to mid-frequencies, at the cost of increased complexity and greater sensitivity to component tolerances.
Best regards, Charles _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
