A 5.4 Gbps Protocol Based CMOS Limiting ReDriver for Type-C Applications

Abstract

PCB traces have high-frequency losses due to skin effect and dielectric losses which result in inter symbol interference (ISI), as the signal passes through cable and PCB traces. A limiting ReDriver, which acts as a repeater and includes a continuous time equalizer, removes the ISI which results in a longer signal reach. A CMOS limiting ReDriver channel operating up to 5.4Gbps and programmable preemphasis and de-emphasis to be compliant with some of the standards like display port (DP) and USB, is presented. It has programmable peaking gain up to 12dB at 2.7GHz with 1.5dB steps to compensate for the channel loss and a programmable output swing control of 400mVpp up to 1100mVppd. It has been implemented in 0.14 um CMOS technology and consumes 37.5mA to 55.5mA per channel from a 1.8V supply, depending on selected output swing and emphasis level. It uses common mode keeper, far-end termination detector and incoming squelch detector to work inside a protocol based ReDriver chip.