Description
In Quartus II software versions prior to 5.0, some of the unused quads RREFB pins were named with the
same pin names as the used quad. This was true for the EP1SGX10C, EP1SGX25C, EP1SGX25D, and the EP1SGX40F devices only. This resulted in these pins being connected together in layout. This is not what was intended.
same pin names as the used quad. This was true for the EP1SGX10C, EP1SGX25C, EP1SGX25D, and the EP1SGX40F devices only. This resulted in these pins being connected together in layout. This is not what was intended.
The change reflects the recommended pin connections for RREFB pins. Each RREFB pin needs to be tied to ground through a resistor. It is not recommended to connect multiple RREFB pins through a single resistor to ground.