"Lock status" in 5150

Hello Zheng,

Sorry for the confusion.  I have attached the diagram of the Configuration Shared Pins of I2C register 03h for explanation and detail how to select lock status.  Basically it is a mux to select what lock status goes to pin 23 and 24.  For example, if you want to output HVLK to pin 23, you need to set bit 6 and reset bit 3 of register 0Fh and set bit 4 of register 03h.  In other case, if bit 4 of register 03h and bit 3 of 0Fh are 0 then FID is output to pin 23.

Lock mean the video is locked.  If HLK is 1 then video horizontal is locked and if VLK is 1 then video vertical is locked.

The TVP5150 is not recommend for new design and you should use TVP5150AM1 if you don't need scaler.

Hope it help,

Viet

Zheng,

The graphs on P16,17, and 18 show the output syncs relative to video out when in a locked state.  HLK an VLK are status signals to show lock status.  HLK and VLK will not change state unless there is a change in lock status. They will be at high level when locked to an inut signal and will go low if the cable is disconnected, for example.  The timing of the HLK and VLK outputs is not precisely synchronized to the video output.  You can also read lock status using I2C register 88h withput using the HLK and VLK status outputs.  The HLK and VLK status outputs cannot be used if HSYNC and VSYNC output syncs are used, since VSYNC and HLK share the same pin.  HLK and VLK status outputs are optional and not used in most designs.

When properly locked to the video input, the output syncs (VSYNC, HSYNC, and BT656 embeddedd syncs) will be properly synchronized and positioned relative to the video.  If a valid NTSC(M,N) or PAL(B,G,H,N,I)  video input signal is connected to the selected input channel, the TVP5150AM1 will automatically lock to the video input, if REG28h is set to the default Autoswitch mode.  To automatically support formats other than these, the autoswitch mask bits in REG04h must be programmed to include the desired formats.

PAL alternates phase of the V color component every line.  PALI is an indicator that the format is PAL and changes state every line when locked to a PAL source.  This signal is rarely used.

When not vertically locked to the input, the VSYNC output and embedded V-bit will not be synchronized to the video input and output.   When unlocked, the video that is displayed on the monitor could depend on how the video processor processes and displays  the video without valid sync signals.   The same video line is not repeated by the TVP5150AM1.