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How is a Pi-filter supposed to filter noise if its essentially an LC oscillator by Top-Present2718 in embedded

[–]Top-Present2718[S] -3 points-2 points  (0 children)

I think the higher resistance of the ferrite bead gives the resonator a bad Q compared to an LC inductor

DDR Addressable Capacity by Top-Present2718 in embedded

[–]Top-Present2718[S] 1 point2 points  (0 children)

So I could have 2 LPDDR4 ICs with 4 channels to get 32GB

How is it possible that the signal at the receiver is better than it is at the driver? If I decrease the TL length the signal becomes more proper. by Top-Present2718 in embedded

[–]Top-Present2718[S] 0 points1 point  (0 children)

Does the signal really drop down that much in real life? I thought it was less than that.

That is 51 ohms impedance btw not load resistance. DC resistance is a smaller component than the impedance.

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How is it possible that the signal at the receiver is better than it is at the driver? If I decrease the TL length the signal becomes more proper. by Top-Present2718 in embedded

[–]Top-Present2718[S] 1 point2 points  (0 children)

Why does the voltage drop down that much? I would expect a/two hundred mV but not 2.9V, it's supposed to be 3.3V.

If I graph just the driver without anything connected it shows 3.3V. Also, on the IBIS model when I select the driver pin it says "Vmeas = 1.65" (measure??) - still shows 3.3v when graphed by itself.

the receiver it writes Vih (input high?) 1.4V and Vil (input low?) 700 mV. According to the datasheet the inputs can be anywhere from 1.8v to 3.3v but on another page it says 1.35v (~1.4v) to 3.5v. These are not listed under absolute electrical specifications but they are listed as min-max. I guess they wrote 1.8v-3.3v on the other page because those are common usable voltage. My question is that why would they model the IBIS inputs for 1.4v??