In designs that use the LVDS I/O standard, receiver input skew margin (RSKM) is the time margin available before the LVDS receiver megafunction fails to operate. RSKM is defined as the total time margin that remains after subtracting the sampling window (SW) size and the transmitter channel-to-channel skew (TCCS) from the time unit interval (TUI), as expressed in the following formula:

RSKM = (TUI - SW - TCCS) /2