Intel® Cyclone® 10 LP Core Fabric and General Purpose I/Os Handbook

ID 683777
Date 2/15/2023
Document Table of Contents

5.6.7. PCI Clamp Diode

The Intel® Cyclone® 10 LP devices are equipped with optional PCI clamp diode that you can enable for the input and output of each I/O pin. You can use this diode to protect I/O pins during voltage overshoot.

The PCI clamp diode is available and enabled by default in the Intel® Quartus® Prime software for the following I/O standards:

  • 3.3 V LVTTL/3.3 V LVCMOS
  • 3.0 V LVTTL/3.0 V LVCMOS
  • 2.5 V LVTTL/2.5 V LVCMOS
  • 3.0 V PCI/PCI-X
Dual-purpose configuration pins support the diode in user mode if you do not use the pins as configuration pins for the selected configuration scheme. For example, if you use the active serial (AS) configuration scheme, you cannot use the clamp diode on the ASDO and nCSO pins in user mode. The dedicated configuration pins do not support the on-chip diode.
Note: For the 3.3 V LVTTL, 3.3 V LVCMOS, 3.0 V LVTTL, and 3.0 V LVCMOS I/O standards, you must enable the PCI clamp diode.