Jeffrey Tyhach

A 90-nm FPGA I/O buffer design with 1.6-Gb/s data rate for source-synchronous system and 300-MHz clock rate for external memory interface

As FPGAs integrate into high-speed systems, performance and signal integrity become more important in I/O design. This paper describes the development of an FPGA design to support 1.6 Gb/s differential source-synchronous standards and 300 MHz external memory interfaces. Speed and performance were achieved using circuits such as differential level-shifters with voltage and temperature compensated current sources, on-chip decoupling capacitors, and floating-well output buffers. Programmable drive strength, output impedance matching, hot-socketing compliance, and 3.3-V voltage tolerance are features of the I/O buffer. In addition, DLLs and programmable phase-offset circuits were used to obtain precise timing control. The chip was manufactured on a 90-nm CMOS process.

A 90 nm FPGA I/O buffer design with 1.6 Gbps data rate for source-synchronous system and 300 MHz clock rate for external memory interface

As FPGAs become more integrated into high-speed systems, high performance I/O with excellent signal integrity becomes more important. This paper describes how these challenges were met on an FPGA developed to support 1.6 Gbps differential source-synchronous standards and 300 MHz external memory interfaces. The I/O buffer features programmable drive strength, output impedance matching, hot-socketing compliance, and 3.3v tolerance. High-speed performance was achieved using design techniques of differential level-shifters with voltage and temperature compensated current sources, on-chip decoupling capacitors, and floating-well output buffers. In addition, DLLs and programmable phase offset circuits were used to obtain precise timing control. The chip was manufactured on a 90 nm CMOS process.

Arria™ 10 device architecture

This paper presents the architecture of Arria 10, a high-density FPGA family built on the TSMC 20SOC process. The design of the device includes an embedded dual-core 1.5 GHz ARM A9 subsystem with peripherals, more than 1M logic elements (LEs) and 1.7M user flip-flops, and 64Mb of embedded memory organized into configurable memory blocks. The Arria 10 family is also the first mainstream FPGA family to include hardened single-precision IEEE 754 floating point, with an aggregate throughput of 1.3 TFLOPs. Device I/O consists of 28G programmable transceivers with an enhanced PMA architecture hardened PCIe sub-blocks and hardened DDR external memory controllers. New methods for digitally-assisted analog calibration are used to address process variation. The fabric is optimized for an aggressive die-size reduction and power improvement over 28nm FPGAs and includes features such as time-borrowing FFs for micro-retiming, tri-stated long-lines for improved routability, programmable back-bias at LAB-cluster granularity and power-management features such as Smart-VID for balancing leakage and performance across the process distribution.