lpcware

DRAM PCB-Layout, works only up to 60 MHz

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by movax on Tue Jan 22 02:47:15 MST 2013
Hi,
I made a double Layer board with an LPC4330 and a 16-bit DRAM. Its working properly up to 60 MHz. Even without series resistors there is no ringing visible on the scope. But the short slopes dont reach the right levels at higher frequencies.
The same code is working on an evaluation board with same DRAM.
Do the traces have too much capacitance? Are the meanders for matching wrong? Is it because of the missing ground layer? Dont know.
I have no experience in routing HF-Circuits and would like to ask for help.

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