Device for automatically trimming resistance of annular substrate and operation method

The invention discloses a device for automatically trimming resistors of an annular substrate and an operation method, and the method comprises the steps: loading the annular substrate on a wafer bearing plate, conveying the annular substrate to a working position under the driving of an original wafer bearing platform of a trimming machine, pressing a probe card to a first group of resistors, trimming the first group of resistors, lifting the probe card through a probe card installation and calibration platform, and turning off a signal lamp. The indexing signal sensor sends a lamp turn-off signal as a rotating signal of the rotating wafer bearing table to the CPU, the CPU controls the second group of resistors of the annular substrate to the position for trimming the first group of resistors, the signal lamp is turned on, the probe card is pressed down to the second group of resistors, the second group of resistors is trimmed until 15 groups of resistors are trimmed, the original wafer bearing table of the