SSTL25 and SSTL18 Stub Resistor

For stub-series interface standard SSTL, the output drive also includes the stub resistor. I/Os support this stub resistor for SSTL25 and SSTL18 I/O standards (Figure 1). This feature reduces both cost and board complexity.

Figure 1. SSTL25 and SSTL18 Stub Resistor