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AD9889BBSTZ-165 resistor swing

Question asked by mariusz81 on Jun 10, 2014
Latest reply on Jul 1, 2014 by mattp

We are using AD9889BBSTZ-165, and we are having issues with some monitors driven by this chip. Some monitors works fine but others appear to lose lock and image flashes.
System condition:
-input clock 148.5MHz,
-external syncs and DE,
-24 bit data (RGB)
- device is set to have registers 0xA2, 0xA3 value 0x87.
-DVI output mode

We noticed that changing swing resistor from 887Ohm to 820Ohm helps with mentioned monitors. Image is not flashing. On other monitors with original value it is working fine.
With the new resistors design works perfectly.
What effect on stability might have changing value of this resistor?
We noticed that some other companies which use same chip was using 750Ohm resistor.
Could you provide more information of influence of swing resistor on system?
What might be implication of changing this resistor?

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