Adaptive Resistance Calibration Circuit for High-speed Serial Transceivers

This work presents an adaptive resistance calibration circuit for high-speed serial transceivers. The structure of the circuit includes resistance calibration unit, amplifier, current mirror, comparator and adaptive algorithm unit. The resistance calibration circuit proposed in this work can accurately adjust the driving impedance of the transmitter (TX) and receiver (RX) in high-speed serial transceivers. Then, by comparing with the external resistance, the proposed circuit can ensure that the total resistance in the resistance calibration unit is consistent with the external one. In this way, the design can effectively avoid the influence of resistance error caused by temperature and process deviation, so as to ensure impedance matching. In summary, all principles and simulation results of the adaptive resistance calibration circuit are presented in detail in this work.