Description
The Stratix® IV GX/GT REFCLK buffer for the transceiver blocks are powered by VCCA (Analog Power) and VCCR (Receiver power). In addition, the VCCT (Transmitter power) provides the power to Inter Transceiver Block (ITB) clock lines used for REFCLK sharing. All power pins must be powered up as stated in the device Pin Connection Guidelines (PDF).