The color burst from AD723 seems to move on AD723 Eval Board.

Hello Tamu,

Yes, you are correct.  The phase varies because the two signals are not synchronous, so cycle-slipping occurs between them.  The NTSC specification requires a fixed 19-cycle phase relationship between the 50% point of the Hsync leading edge and the first rising edge of the colorburst signal, but some systems can operate asynchronously.  If you are using the eval board with the autonomous clock oscillator, you are operating asynchrnously.  Do you have a reference clock available that is synchronous with your sync pulses?  You will need this for synchronous operation.

Best regards.

--Jonathan

Hello Tamu,

Yes, you are correct.  The phase varies because the two signals are not synchronous, so cycle-slipping occurs between them.  The NTSC specification requires a fixed 19-cycle phase relationship between the 50% point of the Hsync leading edge and the first rising edge of the colorburst signal, but some systems can operate asynchronously.  If you are using the eval board with the autonomous clock oscillator, you are operating asynchrnously.  Do you have a reference clock available that is synchronous with your sync pulses?  You will need this for synchronous operation.

Best regards.

--Jonathan