METHODS OF OPERATING MEMORY SYSTEMS IN WHICH AN ACTIVE TERMINATION VALUE FOR A MEMORY DEVICE IS DETERMINED AT A LOW CLOCK FREQUENCY AND COMMANDS ARE APPLIED TO THE MEMORY DEVICE AT A HIGHER CLOCK FREQUENCY

A memory system includes a memory device that includes an active termination circuit. The memory system further includes a controller circuit that includes a frequency control circuit that is configured to modulate a system clock between a first frequency value and a second frequency value, greater than the first frequency value, responsive to a control signal. The controller circuit is further configured to determine an active termination value for the active termination circuit responsive to the system clock at the first frequency value, and to apply commands to the memory device responsive to the system clock at the second frequency value.