A write-tracking circuit for a writable memory array has one or more dummy memory cells and is configured to write different values to the one or more dummy memory cells. Durations of pulses applied to word lines of the memory array during write operations are controlled based on durations of writing the different values to the one or more dummy memory cells. In at least some embodiments, the write-tracking circuit is configured to write the different values to the one or more dummy memory cells during a single write operation. In at least some embodiments, the write-tracking circuit is configured to write the different values to at least one of the one or more dummy memory cells during different write operations.