A 12-Gb/s continuous-time linear equalizer with offset canceller

Abstract

A DC-offset of a continuous-time linear equalizer (CTLE) is cancelled by an analog offset canceller (OFC). The bandwidth (BW) of the OFC is designed to be 10-kHz not to affect the received signal integrity. The BW of the OFC set by an active-RC integrator is lowered by increasing the effective resistance through pulse width modulation (PWM). The input offset of the OFC itself is removed by employing chopping technique. The offset-cancelled CTLE is applied to a four-channel 12-Gb/s wireline receiver compliant with the high-definition multimedia interface (HDMI) version 2.1 standard. The 12-Gb/s wireline receiver has been implemented in a 28-nm CMOS process. The eye opening for the bit-error rate (BER) smaller than 10(-12) becomes larger than 0.26 unit-interval (U1) with the OFC while the BER is always larger than 10(-12) without the OFC.