US Patent 10025685 Impedance compensation based on detecting sensor data

A memory subsystem manages memory I/O impedance compensation by the memory device monitoring a need for impedance compensation. Instead of a memory controller regularly sending a signal to have the memory device update the impedance compensation when a change is not needed, the memory device can indicate when it is ready to perform an impedance compensation change. The memory controller can send an impedance compensation signal to the memory device in response to a compensation flag set by the memory or in response to determining that a sensor value has changed in excess of a threshold.