Signal quality optimization method and a signal quality optimization system

A signal quality optimization method applicable to a first circuit and a second circuit electrically connected to each other, and the signal quality optimization method comprising:

• executing a ZQ calibration process on an off-chip driver (OCD) circuit of the first circuit and an on-die termination (ODT) circuit of the second circuit through a ZQ calibration circuit, so as to obtain a plurality of calibrated resistor quantities corresponding to a plurality of OCD resistances and a plurality of corrected ODT resistances, wherein a plurality of ODT-OCD resistance combinations defines relationships between the corrected ODT resistances and the OCD resistances;
• configuring a processing device to perform a waveform test process for each of the ODT-OCD resistance combinations, wherein the waveform test process includes:
• setting a predetermined time rule to determine an operation success condition between the first circuit and the second circuit;
• and
• adjusting the OCD circuit according to the calibrated resistor quantity corresponding to a target ODT resistance, transmitting a group of test signals between the second circuit and the first circuit, obtaining a signal eye diagram corresponding to the group of test signals, and obtaining an adjustable resistor ratio corresponding to the target ODT resistance by performing repeated adjustments and tests;
• configuring the processing device to extract the OCD resistance value with the highest adjustable resistor ratio for the different ODT resistances, so as to obtain a plurality of preferred ODT-OCD resistance combinations;
• and
• configuring the processing device to configure the ODT circuit and the OCD circuit according to the preferred ODT-OCD resistance combinations, and performing an operation test process for multiple times on the first circuit and the second circuit, so as to obtain an optimized ODT-OCD resistance combination according to test results of the operation test process that is performed for multiple times.