[ADV7280] About the register "LL_NSTD"

Question

Hello 
 
 The phenomenon that the camera cannot display occurs only at low temperatures. 
 When I checked the ADV7280 register values, I found the following differences. 
 Address 0x12: LL_NSTD Nonstandard line length 
 　25 degrees: OFF -20 degrees: ON 
 I checked the waveform of the XTAL clock, but I couldn't see any difference at each temperature. 
 What other waveforms or blocks should I check? 
 
 Best regards, 
 Shioya

PoornimaSubramani · Accepted Answer

Hi, 
 Could you please refer the addressed query at (+) adv7280m doesn't work at the temperature of -15 centigrade - Q&A - Video - EngineerZone (analog.com) , Here expert has given some suggestion about when using the part in low temperature. 
 If possible, Please use the ELPF capacitors with COG (NPO) materials and this material e specially used for extended temp range products like automotive products S ince X7R has very poor temp-coefficient. 
 
 Please note, Due to temperature co-efficient of X7R material, a 10nF might only be 5nF which would put the PLL filter out of specification (PLL filter is sensitive to this). C0G material has a much better temperature co-efficient. 
 
 Thanks, 
 Poornima)

technart · Answer

Hello, thank you for your answer. 
 Please confirm my answer as indicated below. 
 >1) Please check power supplies and power filters are stable at -20C? 
 Power supplies and power filters are stable at -20C. 
 >2) Is your crystal, 28.6363 the correct frequency at -20C? 
 The crystal oscillates at 28.63636 MHz at -20&deg;C. 
 >3) What materials are the ELPF capacitors made of (X7R)? Try C0G (NPO) if possible. 
 CH capacitors are used. 
 > PVDD rail needs ferrite beaded isolation by itself. PVDD needs to be very clean for stability output. 
 Ferrite beads are used before the PVDD input. 
 >Also ensure with "ADI Required Settings" and these are the ones which is found to work over the tested range of >voltage/temperature/inputs 
 Does "ADI Required Settings" have the same meaning as IC default settings? I could not find the words "ADI Required Settings" in the ADV7280 datasheet.

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[ADV7280] About the register "LL_NSTD"

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