gautamcheers
Newbie level 1
HD Video DAC Dynamic Performance: BW/SNR/SFDR/SNDR/...
Hi,
Usually, for SD standards(NTSC,PAL), the video's signal bandwidth(BW) required is 4MHz. This goes upto ~30MHz for HD standards(viz., SMPTE274).
The video signal is normally pre-processed in 8 bits for SD standards. Hence, the expected ENOB from the DAC is 8 bits, which translates into an SNDR/SINAD of ~50dB [SNDR=6.02*bits+1.76] at a 4MHz input signal.
Query: What is the measure of the Dynamic Performance for an HD DAC aimed for say an SMPTE274 application?
In general literature of HD DACs (viz. AD & TI datasheets, HD standards,etc), usually the Luma bandwidth is quoted, or at most the SFDR at 10MHz input video signal (for an appropriate clock frequency of 148.5Msps or 297Msps). But is this enough? Is there NO importance of the ENOB (i.e., SNDR) performance of the DAC at the appropriate video frequency - 30MHz/60MHz? All clarifications/elucidations/links are welcome.
Thanks!
Hi,
Usually, for SD standards(NTSC,PAL), the video's signal bandwidth(BW) required is 4MHz. This goes upto ~30MHz for HD standards(viz., SMPTE274).
The video signal is normally pre-processed in 8 bits for SD standards. Hence, the expected ENOB from the DAC is 8 bits, which translates into an SNDR/SINAD of ~50dB [SNDR=6.02*bits+1.76] at a 4MHz input signal.
Query: What is the measure of the Dynamic Performance for an HD DAC aimed for say an SMPTE274 application?
In general literature of HD DACs (viz. AD & TI datasheets, HD standards,etc), usually the Luma bandwidth is quoted, or at most the SFDR at 10MHz input video signal (for an appropriate clock frequency of 148.5Msps or 297Msps). But is this enough? Is there NO importance of the ENOB (i.e., SNDR) performance of the DAC at the appropriate video frequency - 30MHz/60MHz? All clarifications/elucidations/links are welcome.
Thanks!
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