Cyclone® V Device Handbook: Volume 1: Device Interfaces and Integration

ID 683375
Date 10/18/2023
Document Table of Contents

5.9.4. Dynamic OCT in Cyclone® V Devices

Dynamic OCT is useful for terminating a high-performance bidirectional path by optimizing the signal integrity depending on the direction of the data. Dynamic OCT also helps save power because device termination is internal—termination switches on only during input operation and thus draw less static power.

Note: If you use the SSTL-15, SSTL-135, and SSTL-125 I/O standards with external memory interfaces, Intel recommends that you use OCT with these I/O standards to save board space and cost. OCT reduces the number of external termination resistors used.
Table 57.  Dynamic OCT Based on Bidirectional I/ODynamic RT OCT or RS OCT is enabled or disabled based on whether the bidirectional I/O acts as a receiver or driver.
Dynamic OCT Bidirectional I/O State
Dynamic RT OCT Acts as a receiver Enabled
Acts as a driver Disabled
Dynamic RS OCT Acts as a receiver Disabled
Acts as a driver Enabled
Figure 87. Dynamic RT OCT in Cyclone® V Devices