a) An image drawn on a CRT display remains visible only for a few milliseconds (the persistence of the screen phosphor), unless it is redrawn continuously. This process is called display refresh or screen refresh. Different displays use different refresh rates, but display refresh is normally required between 60 and 80 times a second to avoid any visible screen flickering. 75 times a second is a common refresh rate. In general, a higher refresh rate results in a more stable appearing display. b) Process of restoring the charge in a dynamic memory. Refresh logic must rewrite the contents of the complete RAM periodically (typically 2 ms), called refreshing the memory. See Dynamic Memory.

Regenerative Pulse Distribution Amplifier (Regenerative Pulse DA) – Reconstructs the signal and allows for adjustment of delay. Also see Linear Pulse DA.