Abstract: An improved SATA interface is provided by integrating a power line into a standard ATA interface. One end of the power line is connected to the power pin of the PC and the other end is connected to the power pin of the device, so that the device can draw power from the PC. This saves the power supply design in the external devices, simplifies the device wiring and reduces the manufacture cost.

Abstract: An on-chip termination impedance compensation circuit is provided. The termination impedance generated by the compensation circuit is precise and could absorb the impedance variances resulted from chip manufacturing process, temperature, and noise. The most significant feature of the compensation circuit is that the termination impedance is provided by a digitally calibrated resistor array composed of n+1 resistors in parallel, whose impedances are 20×k×r, 21×k×r, 22×k×r, . . . , 2n×k×r, respectively, where k, r are pre-determined values. By turning on or off each of the n+1 switch devices that are series-connected to the n+1 resistors respectively, the resistor array is able to provide a termination impedance that is k/m times of the external impedance to be compensated.