Datasheet

TFPx01, 403 Errata SLLZ036 - October 2003
3
TO
t
t(FSC)
Transition time between DE transition to SCDT high: 8 DE transitions
2.2 Sync Detect Operation
• Some graphics card when in sleep/standby mode send characters that can make
the DE toggle and make SCDT high, hence in such applications, to robustly
determine if the link is in active or inactive mode, it is recommended that a sync
signal like HSYNC can be used in addition to the SCDT. Timing format on the
recovered HSYNC signal can be used in addition to SCDT to determine if the link
is receiving a valid video format.
• In applications where PD is being pulsed (to save power while in sleep/standby
mode) when the link is inactive, and SCDT is used solely to determine the link
activity, then in such cases SCDT should not be used until 25 ms of signal and
power application.
• There is a rare possibility that SCDT can get stuck high on power up or removal
of the DVI signal. For example: If the power on a DVI distribution box sourcing
the signal to the receiver is cycled rapidly (2-3 times/second), then there is a
small possibility, (1 in ~40-50 times) of cycling power that SCDT may be stuck
high when the box is powered off.