Patent ID: 7557633

Claim:
A data detector comprising: a first level shifter configured to generate first and second level-shifted signals based on a first differential input signal applied from an external device, wherein the first level-shifted signal has a voltage level higher than the first differential input signal, and the first level-shifted signal has a voltage level higher than the second level-shifted signal; and a second level shifter configured to generate third and fourth level-shifted signals based on a second differential input signal applied from an external device, wherein the fourth level-shifted signal has a voltage level higher than the second differential input signal, and the third level-shifted signal has a voltage level higher than the fourth level-shifted signal; a reference current supply circuit configured to supply a first reference current through the first level shifter and a second reference current through the second level shifter; and a comparing circuit configured to compare the first level-shifted signal with the fourth level-shifted signal; and to compare the third level-shifted signal with the second level-shifted signal.