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

ID 683665
Date 10/18/2023
Document Table of Contents

5.7.6. OCT Calibration Block in Stratix V Devices

You can calibrate the OCT using any of the available four to eight OCT calibration blocks , depending on the device density. Each calibration block contains one RZQ pin.

You can use RS and RT OCT in the same I/O bank for different I/O standards if the I/O standards use the same VCCIO supply voltage. You cannot configure the RS OCT and the programmable current strength for the same I/O buffer.

The OCT calibration process uses the RZQ pin that is available in every calibration block in a given I/O bank for series- and parallel-calibrated termination:

  • Connect the RZQ pin to GND through an external 100 Ω or 240 Ω resistor (depending on the RS or RT OCT value).
  • The RZQ pin shares the same VCCIO supply voltage with the I/O bank where the pin is located.
  • The RZQ pin is a dual-purpose I/O pin and functions as a general purpose I/O pin if you do not use the calibration circuit.

Stratix® V devices support calibrated RS and calibrated RT OCT on all I/O pins except for dedicated configuration pins.