APPLICATION NOTE 4133

Using the MAX7461 Loss-of-Sync Alarm to Enable Simple, but Rapid Detection of Standard-Definition Video

By: David Fry

Abstract: The MAX7461 loss-of-sync alarm provides composite sync detection in NTSC, PAL, and SECAM applications. This device is simple to design in and quickly detects the presence or loss of sync within a few lines. The MAX7461 also has the capability to differentiate between SDTV and HDTV syncs. It therefore provides a complete solution to detect the presence or loss of sync with no external components. This enables a system processor to rapidly determine if video signals with valid syncs are present without the overhead of software polling and processing of one or more video inputs.