Agilex™ 7 General-Purpose I/O User Guide: F-Series and I-Series

ID 683780
Date 7/08/2024
Public
Document Table of Contents

2.4.1.1.2. RT OCT

RT OCT with calibration is available only for input and bidirectional pins. Output pins do not support RT OCT with calibration.
  • The RT OCT calibration circuit compares the total impedance of the I/O buffer to the external resistor connected to the RZQ pin.
  • During calibration, the circuit continuously alters the impedance of the I/O buffer until the value reaches the target impedance, which is a predetermined ratio to the reference resistance.
  • The calibration occurs at the end of the device configuration. When the calibration circuit finds the correct impedance, the circuit powers down and stops changing the characteristics of the drivers.
  • You may trigger recalibration during user mode.
Table 12.  Selectable I/O Standards for RT OCT with CalibrationThis table lists the output termination settings for calibrated OCT on different I/O standards.
I/O Standard RT OCT with Calibration (Ω)
SSTL-12 50, 60
POD12 50, 60
HSTL-12 50, 60
Differential SSTL-12 50, 60
Differential POD12 50, 60
Differential HSTL-12 50, 60