Some I/O standards (POD10, POD12, HSUL_12, and DIFF_HSUL_12) require an input termination resistance (R) to a VTT voltage of VCCO (see This Figure).
The DCI input standards supporting single termination are shown in Table: All DCI I/O Standards Supporting Single-Termination DCI .
POD12_DCI |
DIFF_POD12_DCI |
HSUL_12_DCI |
POD10_DCI |
DIFF_POD10_DCI |
DIFF_HSUL_12_DCI |
Single-termination DCI creates a termination to VCCO internally as shown in This Figure. Value of the termination resistor is determined by the ODT attribute. Possible values for ODT:
•POD standards only: RTT_40, RTT_48, and RTT_60
•HSUL_12_DCI and DIFF_HSUL_12_DCI only: RTT_120 and RTT_240
•RTT_NONE
|
For example, to achieve single termination of approximately 50W to VCCO for the POD12_DCI standard, a 240W external precision resistor is required at the VRP pin, ODT must be set to the value RTT_48.