Digitally Controlled Delay Line for a Structured ASIC Having a Via Configurable Fabric for High-Speed Interface

摘要

A Digitally Controlled Delay Line (DCDL) for a Structured ASIC chip is used to delaying input or output signals into or out of core logic in a Structured ASIC. The DCDL has a multi-stage configuration that in a preferred embodiment comprises two fine delay stages for fine tuning the delay using sub-gate delay through an inverter whose delay can be adjusted with parallel CMOS transistors whose gates are biased with a voltage control signal that is thermometer coded. The fine-tune stages are followed by coarse delay stages that use gate-level delay. A DCDL controller outputs control signals that are Grey coded and converted to thermometer coded control signals by a Binary-to-Thermometer Decoder. The DCDL circuit block and accompanying Structured ASIC are manufactured on a 28 nm CMOS process lithographic node or smaller. A high speed routing fabric using a balanced binary tree is employed with the DCDL.