High‐Speed Deterministic‐Latency Serial IO

Abstract

In digital systems, serial IO at speeds in the range from 1 to 20 Gbps is realized by means of dedicated transceivers, named serializer-deserializers (SerDeses). In general, due to their internal architecture, the data transfer delay, or the latency, may vary after a reset of the device. On the other hand, some applications, such as high-speed transfer protocols for analog-to-digital and digital-to-analog converters, trigger and data acquisition systems, clock distribution, synchronization and control of radio equipment need this delay to be constant at each reset. In this chapter, we focus on a serial IO architecture based on configurable transceivers embedded in field-programmable gate arrays (FPGAs). We will show how it is possible to achieve deterministic-latency operation in a line-codeindependent way. As a case study, we will consider a synchronous 2.5-Gbps serial link based on an 8b10b line code.