Patent ID: 11936356
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Basic communication processes (Electrical engineering)
Classification: CPC G  H | IPC H

Claim 9:
10. An impedance matching circuit comprising:
an external resistor connected between a first node and ground;
a first resistance unit connected to the first node;
a second resistance unit connected between a second node and the ground;
a reference voltage generator configured to generate a reference voltage; and
a code generator configured to generate a first calibration code by comparing the reference voltage with a first voltage associated with the first node and a second calibration code by comparing the reference voltage with a second voltage associated with the second node, wherein:
the first resistance unit, in response to the first calibration code, is configured to calibrate its resistance to be substantially equal to a reference resistance;
the second resistance unit, in response to the second calibration code, is configured to calibrate its resistance to be substantially equal to the reference resistance;
the code generator comprises a first multiplexer and a comparator; and
the first multiplexer selects one of the first voltage and the second voltage and provides the selected voltage to a first input terminal of the comparator.