AnsweredAssumed Answered

ADV7181C: unstable LLC, hot case

Question asked by CoTr on Apr 21, 2014
Latest reply on Apr 21, 2014 by CoTr

Hello Everybody.

I have a trouble with ADV7181c.

A motherboard has 2 ADV7181c for decode Y/C signals to 8bit-YUV. I can't force to do it.

What I see: I get the data but LLC has strong jitter and the data are unstable, video image is twitch.

Moreover, the case is very hot. It's more than 80 grad C. The powers +3.3V, +1.8V are stable.

 

What I send to there via I2C:

for YC:

.DB $0F,$80 ; Reset to default

.DB $06,$02          ; VID_STD

.DB $13,$04          ; external TTL

.DB $3A,%00010000 ; Turn On 3,4 ADC only

.DB $69,%00000011     ; sdm_sel Y/C to AIN2 and AIN3

.DB $C3, $42 ; Manual Muxing - ADC0=AIN2(Y), ADC1=AIN3(C)

 

The XTAL is 27.000 MHz from Altera's PLL.

 

What have I do to fix it?

 

PS. Is it correct to set to XTAL the 27 MHz, not 28.6363?

 

Thanks.

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