【应用笔记】在Stratix III器件中实现片上终端(on-chip termination,OCT)校正(Implementing OCT Calibration in Stratix III Devices)
片上终端(on-chip termination,OCT)方案在Stratix III器件中的使用，消除了外部串行或并行终端电阻的需要，简化了PCB设计。Stratix III器件在所有I/O块上对单端I/O标准，支持可校准的片上串行、并行和动态终端。
Use of the on-chip termination (OCT) scheme in Stratix® III devices
eliminates the need for external series or parallel termination resistors
and simplifies the design of a PCB. Stratix III devices support calibrated
on-chip series, parallel and dynamic termination in all I/O banks for
single-ended I/O standards. OCT calibration allows you to establish an
optimal termination value that compensates impedance change due to
temperature and voltage fluctuation. You can enable Stratix III devices
calibration by user-controlled signals during device operation or by
default during device configuration.
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