A Programmable Pre-emphasis Transmitter for SerDes in 40 nm CMOS

Based on 40 nm standard CMOS process, this paper proposes an easy realized, programmable pre-emphasis transmitter. The circuit is used in high performance SerDes (Serializer-Deserializer) chip, which utilizes a 2-tap current-mode pre-emphasis technique, resulting less design complicacy as well as low noise. Furthermore, a tail current DAC enables equalization to be configurable in order to adapt to various data rate condition. Simulation results show 0–6 db pre-emphasis ability and 0–1.3 V differential output voltage swing under 2.5–6.25 GB/s transmission rate, which meet specifications of high speed serial link standards such as PCIE2.1 and RapidIO2.2.