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ADV7123 tricky datasheet rev D,

Question asked by U=RI on May 29, 2013
Latest reply on Jun 4, 2013 by DaveD

HI,

 

first of all, please appologise my very bad english because I'm french (ok I know this is not an excuse)....

 

I'm currently use a ADV7123 in a R/G/B pal generator without any problem..

 

nevertheless I cannot find this simple figure : where could I find LSB current setting....... Vref/Rset allright !

p.11 / 24 i can read

Ior=7989.6*Vref/Rset is the relationship between Rset and the full-scale let's Rset=530 ohm

Ior=7989.6*1.235/530=18.61028mA right? (1)

 

so guess what I read on figure 23 page 17/24 ? white level is 18.67mA for the same Rset!  Ooops.....

 

anyway let's try another time....

in 3.3V specification p4 "analog outputs/output current RGBDAC max is 18.5mA with Rset=560 ohm....

Ior=7989.6*1.235/560=17.61mA Oooooopssss!

 

last chance :

Table 9 , p18 Rset=530 current full scale for Ior is 18.67mA (0x3FF) Oooooopsssss......

 

so , who's right?, why swinging between Rset=530 and Rset=560 everywhere?

 

puzzled!

 

by the way the value 1023 in hex format is 0x3FF and not 0x3FFH in table 9.......

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