SPRABI1D January 2018 – July 2022 66AK2E05 , 66AK2G12 , 66AK2H06 , 66AK2H12 , 66AK2H14 , 66AK2L06 , AM5K2E02 , AM5K2E04 , SM320C6678-HIREL , TMS320C6652 , TMS320C6654 , TMS320C6655 , TMS320C6657 , TMS320C6670 , TMS320C6671 , TMS320C6672 , TMS320C6674 , TMS320C6678
The DDR3 SDRAM termination voltage is referred to as VTT and requires a 750-mV supply. The recommended VTT source is a regulator that is capable of sinking a sufficient amount of current while at the same time maintaining a tight voltage tolerance. Like the Vref pins, the distance between the VTT source voltage and SDRAM pin must be short and decoupled properly. The VTT pin must be kept stable and properly track the VDD/VDDq variations over voltage, noise, and temperature differences. The pk-to-pk AC and DC noise on the VTT pin cannot exceed ±2% or 1.5 mV.