I have schematic for decoupling capacitors (3 set of 0.1uF,1nF,10pF): And I've implemented that in this way: And there is ADI reference for easy evaluation: And the ground pins of decoupling caps will all connected to ground by polygone containing all pins in top and bottom. Also we have two stranger, 12GHz differential pair + clock trace. Is it acceptable? Do not tell anything and listen to the notes please.
Note:
The board have 4 layer 1.RF 2.GND(unbroken) 3.AVDD(unbroken) 4.signal
And as you can (have to!) see I have connected 3 AVDD pins of IC, together (by polygon), but the 3 AGND's are exactly in left side of the differential 12GHz pair. Unfortunately I will connect the top capacitors to two pin in left-side of C1's GND, because they are GND but are Digital GND (datasheet called them DGND and SDGND).I have idea it will be nice if I can place a bigger size (like 1204) of one of capacitors to bridge the right and left of differential pair, is it good idea (I prefer 1nF)?
Finally
The questions are:
|.Is it acceptable decoupling, rate it and if is poor give alternate idea
||.Is it good idea to bridge two side of differential pair? (because I think the bypasses must be between same GND & VDD but in this case they are not in good placement)
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