SN74SSTUB32864 25-Bit Configurable Register Buffer Texas Instruments SN74SSTUB32864 25-Bit Configurable Register Buffer is designed for 1.7V to 1.9V VCC operation. In the 1:1 pinout configuration, only one device per DIMM is required to drive nine SDRAM loads. In the 1:2 pinout configuration, two devices per DIMM are required to drive eighteen SDRAM loads. All inputs are SSTL_18, except the reset (RESET) and control (Cn) inputs, which are LVCMOS. All outputs are edge-controlled circuits optimized for unterminated DIMM loads and meet SSTL_18 specifications.